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PIC18CXX2 Data Sheet
High Performance Microcontrollers with 10-bit A/D
2001 Microchip Technology Inc.
DS39026C
"All rights reserved. Copyright (c) 2001, Microchip Technology Incorporated, USA. Information contained in this publication regarding device applications and the like is intended through suggestion only and may be superseded by updates. No representation or warranty is given and no liability is assumed by Microchip Technology Incorporated with respect to the accuracy or use of such information, or infringement of patents or other intellectual property rights arising from such use or otherwise. Use of Microchip's products as critical components in life support systems is not authorized except with express written approval by Microchip. No licenses are conveyed, implicitly or otherwise, under any intellectual property rights. The Microchip logo and name are registered trademarks of Microchip Technology Inc. in the U.S.A. and other countries. All rights reserved. All other trademarks mentioned herein are the property of their respective companies. No licenses are conveyed, implicitly or otherwise, under any intellectual property rights."
Trademarks The Microchip name, logo, PIC, PICmicro, PICMASTER, PICSTART, PRO MATE, KEELOQ, SEEVAL, MPLAB and The Embedded Control Solutions Company are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. Total Endurance, ICSP, In-Circuit Serial Programming, FilterLab, MXDEV, microID, FlexROM, fuzzyLAB, MPASM, MPLINK, MPLIB, PICDEM, ICEPIC, Migratable Memory, FanSense, ECONOMONITOR, Select Mode and microPort are trademarks of Microchip Technology Incorporated in the U.S.A. Serialized Quick Term Programming (SQTP) is a service mark of Microchip Technology Incorporated in the U.S.A. All other trademarks mentioned herein are property of their respective companies. (c) 2001, Microchip Technology Incorporated, Printed in the U.S.A., All Rights Reserved.
Microchip received QS-9000 quality system certification for its worldwide headquarters, design and wafer fabrication facilities in Chandler and Tempe, Arizona in July 1999. The Company's quality system processes and procedures are QS-9000 compliant for its PICmicro(R) 8-bit MCUs, KEELOQ(R) code hopping devices, Serial EEPROMs and microperipheral products. In addition, Microchip's quality system for the design and manufacture of development systems is ISO 9001 certified.
DS39026C - page ii
2001 Microchip Technology Inc.
PIC18CXX2
High Performance Microcontrollers with 10-bit A/D
High Performance RISC CPU:
* C compiler optimized architecture/instruction set - Source code compatible with the PIC16CXX instruction set * Linear program memory addressing to 2 Mbytes * Linear data memory addressing to 4 Kbytes
On-Chip Program Memory Device EPROM (bytes) 16K 32K 16K 32K # Single Word Instructions 8192 16384 8192 16384 On-Chip RAM (bytes) 512 1536 512 1536
Pin Diagrams
DIP, Windowed CERDIP
MCLR/VPP RA0/AN0 RA1/AN1 RA2/AN2/VREFRA3/AN3/VREF+ RA4/T0CKI RA5/AN4/SS/LVDIN RE0/RD/AN5 RE1/WR/AN6 RE2/CS/AN7 VDD VSS OSC1/CLKI OSC2/CLKO/RA6 RC0/T1OSO/T1CKI RC1/T1OSI/CCP2* RC2/CCP1 RC3/SCK/SCL RD0/PSP0 RD1/PSP1 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 40 39 38 37 36 35 34 33 32 31 30 29 28 27 26 25 24 23 22 21 RB7 RB6 RB5 RB4 RB3/CCP2* RB2/INT2 RB1/INT1 RB0/INT0 VDD VSS RD7/PSP7 RD6/PSP6 RD5/PSP5 RD4/PSP4 RC7/RX/DT RC6/TX/CK RC5/SDO RC4/SDI/SDA RD3/PSP3 RD2/PSP2
PIC18C242 PIC18C252 PIC18C442 PIC18C452
* Up to 10 MIPs operation: - DC - 40 MHz osc./clock input - 4 MHz - 10 MHz osc./clock input with PLL active * 16-bit wide instructions, 8-bit wide data path * Priority levels for interrupts * 8 x 8 Single Cycle Hardware Multiplier
* RB3 is the alternate pin for the CCP2 pin multiplexing. Note: Pin compatible with 40-pin PIC16C7X devices.
Analog Features:
* Compatible 10-bit Analog-to-Digital Converter module (A/D) with: - Fast sampling rate - Conversion available during SLEEP - DNL = 1 LSb, INL = 1 LSb * Programmable Low Voltage Detection (LVD) module - Supports interrupt-on-low voltage detection * Programmable Brown-out Reset (BOR)
Peripheral Features:
* High current sink/source 25 mA/25 mA * Three external interrupt pins * Timer0 module: 8-bit/16-bit timer/counter with 8-bit programmable prescaler * Timer1 module: 16-bit timer/counter * Timer2 module: 8-bit timer/counter with 8-bit period register (time-base for PWM) * Timer3 module: 16-bit timer/counter * Secondary oscillator clock option - Timer1/Timer3 * Two Capture/Compare/PWM (CCP) modules. CCP pins that can be configured as: - Capture input: capture is 16-bit, max. resolution 6.25 ns (TCY/16) - Compare is 16-bit, max. resolution 100 ns (TCY) - PWM output: PWM resolution is 1- to 10-bit. Max. PWM freq. @: 8-bit resolution = 156 kHz 10-bit resolution = 39 kHz * Master Synchronous Serial Port (MSSP) module. Two modes of operation: - 3-wire SPITM (supports all 4 SPI modes) - I2CTM master and slave mode * Addressable USART module: - Supports interrupt on Address bit * Parallel Slave Port (PSP) module
Special Microcontroller Features:
* Power-on Reset (POR), Power-up Timer (PWRT) and Oscillator Start-up Timer (OST) * Watchdog Timer (WDT) with its own on-chip RC oscillator for reliable operation * Programmable code protection * Power saving SLEEP mode * Selectable oscillator options including: - 4X Phase Lock Loop (of primary oscillator) - Secondary Oscillator (32 kHz) clock input * In-Circuit Serial Programming (ICSPTM) via two pins
CMOS Technology:
* * * * * Low power, high speed EPROM technology Fully static design Wide operating voltage range (2.5V to 5.5V) Industrial and Extended temperature ranges Low power consumption
2001 Microchip Technology Inc.
PIC18C4X2
DS39026C-page 1
PIC18CXX2
Pin Diagrams
RA3/AN3/VREF+ RA2/AN2/VREFRA1/AN1 RA0/AN0 MCLR/VPP NC RB7 RB6 RB5 RB4 NC 6 5 4 3 2 1 44 43 42 41 40 39 38 37 36 35 34 33 32 31 30 29
PLCC
RA4/T0CKI RA5/AN4/SS/LVDIN RE0/RD/AN5 RE1/WR/AN6 RE2/CS/AN7 VDD VSS OSC1/CLKI OSC2/CLKO/RA6 RC0/T1OSO/T1CKI NC
7 8 9 10 11 12 13 14 15 16 171
PIC18C4X2
RB3/CCP2* RB2/INT2 RB1/INT1 RB0/INT0 VDD VSS RD7/PSP7 RD6/PSP6 RD5/PSP5 RD4/PSP4 RC7/RX/DT
TQFP
44 43 42 41 40 39 38 37 36 35 34 RC7/RX/DT RD4/PSP4 RD5/PSP5 RD6/PSP6 RD7/PSP7 VSS VDD RB0/INT0 RB1/INT1 RB2/INT2 RB3/CCP2* 1 2 3 4 5 6 7 8 9 10 11 33 32 31 30 29 28 27 26 25 24 23 NC RC0/T1OSO/T1CKI OSC2/CLKO/RA6 OSC1/CLKI VSS VDD RE2/AN7/CS RE1/AN6/WR RE0/AN5/RD RA5/AN4/SS/LVDIN RA4/T0CKI
* RB3 is the alternate pin for the CCP2 pin multiplexing.
Note: Pin compatible with 44-pin PIC16C7X devices.
RC6/TX/CK RC5/SDO RC4/SDI/SDA RD3/PSP3 RD2/PSP2 RD1/PSP1 RD0/PSP0 RC3/SCK/SCL RC2/CCP1 RC1/T1OSI/CCP2* NC
28 27 26 25 24 23 22 21 20 19 8 NC RC6/TX/CK RC5/SDO RC4/SDI/SDA RD3/PSP3 RD2/PSP2 RD1/PSP1 RD0/PSP0 RC3/SCK/SCL RC2/CCP1 RC1/T1OSI/CCP2*
PIC18C4X2
22 21 20 19 18 17 16 15 14 13 12
RA3/AN3/VREF+ RA2/AN2/VREFRA1/AN1 RA0/AN0 MCLR/VPP RB7 RB6 RB5 RB4 NC NC
DS39026C-page 2
2001 Microchip Technology Inc.
PIC18CXX2
Pin Diagrams (Cont.'d) DIP, JW
MCLR/VPP RA0/AN0 RA1/AN1 RA2/AN2/VREFRA3/AN3/VREF+ RA4/T0CKI RA5/AN4/SS/LVDIN RE0/RD/AN5 RE1/WR/AN6 RE2/CS/AN7 VDD VSS OSC1/CLKI OSC2/CLKO/RA6 RC0/T1OSO/T1CKI RC1/T1OSI/CCP2* RC2/CCP1 RC3/SCK/SCL RD0/PSP0 RD1/PSP1 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 40 39 38 37 36 35 34 33 32 31 30 29 28 27 26 25 24 23 22 21 RB7 RB6 RB5 RB4 RB3/CCP2* RB2/INT2 RB1/INT1 RB0/INT0 VDD VSS RD7/PSP7 RD6/PSP6 RD5/PSP5 RD4/PSP4 RC7/RX/DT RC6/TX/CK RC5/SDO RC4/SDI/SDA RD3/PSP3 RD2/PSP2
Note: Pin compatible with 40-pin PIC16C7X devices.
DIP, SOIC, JW
MCLR/VPP RA0/AN0 RA1/AN1 RA2/AN2/VREFRA3/AN3/VREF+ RA4/T0CKI RA5/AN4/SS/LVDIN VSS OSC1/CLKI OSC2/CLKO/RA6 RC0/T1OSO/T1CKI RC1/T1OSI/CCP2* RC2/CCP1 RC3/SCK/SCL 1 2 3 4 5 6 7 8 9 10 11 12 13 14 28 27 26 25 24 23 22 21 20 19 18 17 16 15 RB7 RB6 RB5 RB4 RB3/CCP2* RB2/INT2 RB1/INT1 RB0/INT0 VDD VSS RC7/RX/DT RC6/TX/CK RC5/SDO RC4/SDI/SDA
* RB3 is the alternate pin for the CCP2 pin multiplexing.
Note: Pin compatible with 28-pin PIC16C7X devices.
2001 Microchip Technology Inc.
PIC18C2X2
PIC18C4X2
DS39026C-page 3
PIC18CXX2
Table of Contents
1.0 Device Overview ......................................................................................................................................................................... 7 2.0 Oscillator Configurations........................................................................................................................................................... 17 3.0 Reset......................................................................................................................................................................................... 25 4.0 Memory Organization................................................................................................................................................................ 35 5.0 Table Reads/Table Writes ........................................................................................................................................................ 55 6.0 8 X 8 Hardware Multiplier.......................................................................................................................................................... 61 7.0 Interrupts................................................................................................................................................................................... 63 8.0 I/O Ports.................................................................................................................................................................................... 77 9.0 Timer0 Module .......................................................................................................................................................................... 93 10.0 Timer1 Module .......................................................................................................................................................................... 97 11.0 Timer2 Module ........................................................................................................................................................................ 101 12.0 Timer3 Module ........................................................................................................................................................................ 103 13.0 Capture/Compare/PWM (CCP) Modules ................................................................................................................................ 107 14.0 Master Synchronous Serial Port (MSSP) Module................................................................................................................... 115 15.0 Addressable Universal Synchronous Asynchronous Receiver Transmitter (USART) ............................................................ 149 16.0 Compatible 10-bit Analog-to-Digital Converter (A/D) Module ................................................................................................. 165 17.0 Low Voltage Detect................................................................................................................................................................. 173 18.0 Special Features of the CPU .................................................................................................................................................. 179 19.0 Instruction Set Summary......................................................................................................................................................... 187 20.0 Development Support ............................................................................................................................................................. 229 21.0 Electrical Characteristics......................................................................................................................................................... 235 22.0 DC and AC Characteristics Graphs and Tables ..................................................................................................................... 263 23.0 Packaging Information ............................................................................................................................................................ 277 Appendix A: Revision History ......................................................................................................................................................... 287 Appendix B: Device Differences..................................................................................................................................................... 287 Appendix C: Conversion Considerations........................................................................................................................................ 288 Appendix D: Migration from Baseline to Enhanced Devices .......................................................................................................... 288 Appendix E: Migration from Mid-Range to Enhanced Devices ...................................................................................................... 289 Appendix F: Migration from High-End to Enhanced Devices ......................................................................................................... 289 Index ................................................................................................................................................................................................. 291 On-Line Support................................................................................................................................................................................ 299 Reader Response ............................................................................................................................................................................. 300 PIC18CXX2 Product Identification System ....................................................................................................................................... 301
DS39026C-page 4
2001 Microchip Technology Inc.
PIC18CXX2
TO OUR VALUED CUSTOMERS
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Errata
An errata sheet, describing minor operational differences from the data sheet and recommended workarounds, may exist for current devices. As device/documentation issues become known to us, we will publish an errata sheet. The errata will specify the revision of silicon and revision of document to which it applies. To determine if an errata sheet exists for a particular device, please check with one of the following: * Microchip's Worldwide Web site; http://www.microchip.com * Your local Microchip sales office (see last page) * The Microchip Corporate Literature Center; U.S. FAX: (480) 792-7277 When contacting a sales office or the literature center, please specify which device, revision of silicon and data sheet (include literature number) you are using.
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2001 Microchip Technology Inc.
DS39026C-page 5
PIC18CXX2
NOTES:
DS39026C-page 6
2001 Microchip Technology Inc.
PIC18CXX2
1.0 DEVICE OVERVIEW
This document contains device specific information for the following four devices: 1. 2. 3. 4. PIC18C242 PIC18C252 PIC18C442 PIC18C452 The following two figures are device block diagrams sorted by pin count: 28-pin for Figure 1-1 and 40-pin for Figure 1-2. The 28-pin and 40-pin pinouts are listed in Table 1-2 and Table 1-3, respectively.
These devices come in 28-pin and 40-pin packages. The 28-pin devices do not have a Parallel Slave Port (PSP) implemented and the number of Analog-toDigital (A/D) converter input channels is reduced to 5. An overview of features is shown in Table 1-1.
TABLE 1-1:
DEVICE FEATURES
PIC18C242 DC - 40 MHz 16K 8192 512 16 Ports A, B, C 4 2 MSSP, Addressable USART -- 5 input channels PIC18C252 DC - 40 MHz 32K 16384 1536 16 Ports A, B, C 4 2 MSSP, Addressable USART -- 5 input channels PIC18C442 DC - 40 MHz 16K 8192 512 17 4 2 MSSP, Addressable USART PSP 8 input channels PIC18C452 DC - 40 MHz 32K 16384 1536 17 4 2 MSSP, Addressable USART PSP 8 input channels
Features Operating Frequency Program Memory (Bytes) Program Memory (Instructions) Data Memory (Bytes) Interrupt Sources I/O Ports Timers Capture/Compare/PWM Modules Serial Communications
Ports A, B, C, D, E Ports A, B, C, D, E
Parallel Communications 10-bit Analog-to-Digital Module RESETS (and Delays)
POR, BOR, POR, BOR, RESET Instruction, RESET Instruction, Stack Full, Stack Full, Stack Underflow Stack Underflow (PWRT, OST) (PWRT, OST) Yes Yes 75 Instructions 28-pin DIP 28-pin SOIC 28-pin JW Yes Yes 75 Instructions 28-pin DIP 28-pin SOIC 28-pin JW
POR, BOR, POR, BOR, RESET Instruction, RESET Instruction, Stack Full, Stack Full, Stack Underflow Stack Underflow (PWRT, OST) (PWRT, OST) Yes Yes 75 Instructions 40-pin DIP 44-pin PLCC 44-pin TQFP 40-pin JW Yes Yes 75 Instructions 40-pin DIP 44-pin PLCC 44-pin TQFP 40-pin JW
Programmable Low Voltage Detect Programmable Brown-out Reset Instruction Set Packages
2001 Microchip Technology Inc.
DS39026C-page 7
PIC18CXX2
FIGURE 1-1: PIC18C2X2 BLOCK DIAGRAM
Data Bus<8>
21 21 21
Address Latch Program Memory (up to 2M Bytes) Data Latch
Table Pointer <2>
Data Latch
PORTA RA0/AN0 RA1/AN1 RA2/AN2/VREFRA3/AN3/VREF+ RA4/T0CKI RA5/AN4/SS/LVDIN RA6
8
inc/dec logic
8
8
Data RAM
Address Latch
20
PCLATU PCLATH
12
(2)
PCU PCH PCL Program Counter
Address<12>
4
BSR
12
FSR0 FSR1 FSR2 inc/dec logic
4
Bank0, F
31 Level Stack
12
16
Table Latch
Decode
8
ROM Latch
PORTB RB0/INT0 RB1/INT1 RB2/INT2 RB3/CCP2(1) RB7:RB4
Instruction Register
Instruction Decode & Control OSC2/CLKO OSC1/CLKI Timing Generation T1OSI T1OSO 4X PLL
8
PRODH PRODL
3
Power-up Timer Oscillator Start-up Timer Power-on Reset Watchdog Timer Brown-out Reset BIT OP
8 x 8 Multiply
8
WREG
8 8
8
8
ALU<8>
PORTC RC0/T1OSO/T1CKI RC1/T1OSI/CCP2(1) RC2/CCP1 RC3/SCK/SCL RC4/SDI/SDA RC5/SDO RC6/TX/CK RC7/RX/DT
Precision Voltage Reference
8
MCLR
VDD, VSS
Timer0
Timer1
Timer2
Timer3
A/D Converter
CCP1
CCP2
Master Synchronous Serial Port
Addressable USART
Note
1: Optional multiplexing of CCP2 input/output with RB3 is enabled by selection of configuration bit. 2: The high order bits of the Direct Address for the RAM are from the BSR register (except for the MOVFF instruction). 3: Many of the general purpose I/O pins are multiplexed with one or more peripheral module functions. The multiplexing combinations are device dependent.
DS39026C-page 8
2001 Microchip Technology Inc.
PIC18CXX2
FIGURE 1-2: PIC18C4X2 BLOCK DIAGRAM
Data Bus<8> PORTA 21 21 21 Address Latch Program Memory (up to 2M Bytes) Data Latch 31 Level Stack 20
PCLATU PCLATH
Table Pointer <2>
Data Latch 8 8 8 Data RAM (up to 4K address reach) Address Latch 12 Address<12> 4
BSR
(2)
inc/dec logic
RA0/AN0 RA1/AN1 RA2/AN2/VREFRA3/AN3/VREF+ RA4/T0CKI RA5/AN4/SS/LVDIN RA6
PCU PCH PCL Program Counter
12 FSR0 FSR1 FSR2
inc/dec logic
4
Bank0, F
PORTB RB0/INT0 RB1/INT1 RB2/INT2 RB3/CCP2(1) RB7:RB4
12
16
Table Latch
Decode 8
ROM Latch
PORTC RC0/T1OSO/T1CKI RC1/T1OSI/CCP2(1) RC2/CCP1 RC3/SCK/SCL RC4/SDI/SDA RC5/SDO RC6/TX/CK RC7/RX/DT
Instruction Register
Instruction Decode & Control OSC2/CLKO OSC1/CLKI Timing Generation T1OSI T1OSO 4X PLL 3 Power-up Timer Oscillator Start-up Timer Power-on Reset Watchdog Timer Brown-out Reset
8 PRODH PRODL 8 x 8 Multiply 8 BIT OP 8 WREG 8 8 ALU<8> 8 PORTE 8 PORTD
RD0/PSP0 RD1/PSP1 RD2/PSP2 RD3/PSP3 RD4/PSP4 RD5/PSP5 RD6/PSP6 RD7/PSP7
Precision Voltage Reference
RE0/AN5/RD MCLR VDD, VSS RE1/AN6/WR RE2/AN7/CS
Timer0
Timer1
Timer2
Timer3
A/D Converter
CCP1
CCP2
Master Synchronous Serial Port
Addressable USART
Parallel Slave Port
Note
1: Optional multiplexing of CCP2 input/output with RB3 is enabled by selection of configuration bit. 2: The high order bits of the Direct Address for the RAM are from the BSR register (except for the MOVFF instruction). 3: Many of the general purpose I/O pins are multiplexed with one or more peripheral module functions. The multiplexing combinations are device dependent.
2001 Microchip Technology Inc.
DS39026C-page 9
PIC18CXX2
TABLE 1-2:
Pin Name DIP MCLR/VPP MCLR VPP NC OSC1/CLKI OSC1 CLKI -- 9 -- 9 1
PIC18C2X2 PINOUT I/O DESCRIPTIONS
Pin Number Pin Type SOIC 1 I P -- I I ST Buffer Type Description Master clear (input) or programming voltage (input). Master Clear (Reset) input. This pin is an active low RESET to the device. Programming voltage input. These pins should be left unconnected. Oscillator crystal or external clock input. Oscillator crystal input or external clock source input. ST buffer when configured in RC mode. CMOS otherwise. External clock source input. Always associated with pin function OSC1. (See related OSC1/CLKIN, OSC2/CLKOUT pins.) Oscillator crystal or clock output. Oscillator crystal output. Connects to crystal or resonator in Crystal Oscillator mode. In RC mode, OSC2 pin outputs CLKOUT which has 1/4 the frequency of OSC1, and denotes the instruction cycle rate. General Purpose I/O pin. PORTA is a bi-directional I/O port.
-- ST CMOS
OSC2/CLKO/RA6 OSC2 CLKO
10
10 O O -- --
RA6
I/O
TTL
RA0/AN0 2 2 RA0 I/O TTL Digital I/O. AN0 I Analog Analog input 0. RA1/AN1 3 3 RA1 I/O TTL Digital I/O. AN1 I Analog Analog input 1. 4 4 RA2/AN2/VREFI/O TTL Digital I/O. RA2 I Analog Analog input 2. AN2 I Analog A/D Reference Voltage (Low) input. VREF5 5 RA3/AN3/VREF+ I/O TTL Digital I/O. RA3 I Analog Analog input 3. AN3 I Analog A/D Reference Voltage (High) input. VREF+ RA4/T0CKI 6 6 RA4 I/O ST/OD Digital I/O. Open drain when configured as output. T0CKI I ST Timer0 external clock input. RA5/AN4/SS/LVDIN 7 7 RA5 I/O TTL Digital I/O. AN4 I Analog Analog input 4. SS I ST SPI Slave Select input. LVDIN I Analog Low Voltage Detect Input. RA6 See the OSC2/CLKO/RA6 pin. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels I = Input O = Output P = Power OD = Open Drain (no P diode to VDD)
DS39026C-page 10
2001 Microchip Technology Inc.
PIC18CXX2
TABLE 1-2:
Pin Name DIP
PIC18C2X2 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number Pin Type SOIC Buffer Type Description PORTB is a bi-directional I/O port. PORTB can be software programmed for internal weak pull-ups on all inputs.
Digital I/O. Capture2 input, Compare2 output, PWM2 output. 25 25 Digital I/O. Interrupt-on-change pin. RB5 26 26 I/O TTL Digital I/O. Interrupt-on-change pin. RB6 27 27 I/O TTL Digital I/O. Interrupt-on-change pin. I ST ICSP programming clock. RB7 28 28 I/O TTL Digital I/O. Interrupt-on-change pin. I/O ST ICSP programming data. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels I = Input O = Output P = Power OD = Open Drain (no P diode to VDD)
RB0/INT0 RB0 INT0 RB1/INT1 RB1 INT1 RB2/INT2 RB2 INT2 RB3/CCP2 RB3 CCP2 RB4
21
21 I/O I TTL ST TTL ST TTL ST TTL ST TTL Digital I/O. External Interrupt 0.
22
22 I/O I External Interrupt 1. Digital I/O. External Interrupt 2.
23
23 I/O I
24
24 I/O I/O I/O
2001 Microchip Technology Inc.
DS39026C-page 11
PIC18CXX2
TABLE 1-2:
Pin Name DIP
PIC18C2X2 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number Pin Type SOIC Buffer Type Description PORTC is a bi-directional I/O port.
RC0/T1OSO/T1CKI 11 11 RC0 I/O ST Digital I/O. T1OSO O -- Timer1 oscillator output. T1CKI I ST Timer1/Timer3 external clock input. RC1/T1OSI/CCP2 12 12 RC1 I/O ST Digital I/O. T1OSI I CMOS Timer1 oscillator input. CCP2 I/O ST Capture2 input, Compare2 output, PWM2 output. RC2/CCP1 13 13 RC2 I/O ST Digital I/O. CCP1 I/O ST Capture1 input/Compare1 output/PWM1 output. RC3/SCK/SCL 14 14 RC3 I/O ST Digital I/O. SCK I/O ST Synchronous serial clock input/output for SPI mode. SCL I/O ST Synchronous serial clock input/output for I2C mode. RC4/SDI/SDA 15 15 RC4 I/O ST Digital I/O. ST SPI Data In. SDI I I/O ST I2C Data I/O. SDA RC5/SDO 16 16 RC5 I/O ST Digital I/O. SDO O -- SPI Data Out. RC6/TX/CK 17 17 RC6 I/O ST Digital I/O. TX O -- USART Asynchronous Transmit. I/O ST USART Synchronous Clock (see related RX/DT). CK RC7/RX/DT 18 18 RC7 I/O ST Digital I/O. RX I ST USART Asynchronous Receive. DT I/O ST USART Synchronous Data (see related TX/CK). 8, 19 8, 19 P -- Ground reference for logic and I/O pins. VSS VDD 20 20 P -- Positive supply for logic and I/O pins. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels I = Input O = Output P = Power OD = Open Drain (no P diode to VDD)
DS39026C-page 12
2001 Microchip Technology Inc.
PIC18CXX2
TABLE 1-3:
Pin Name DIP MCLR/VPP MCLR VPP NC OSC1/CLKI OSC1 CLKI -- 13 14 30 I I 1
PIC18C4X2 PINOUT I/O DESCRIPTIONS
Pin Number Pin Type PLCC TQFP 2 18 I P -- Buffer Type Description
OSC2/CLKO/RA6 OSC2 CLKO
14
15
31 O O
RA6
I/O
Master clear (input) or programming voltage (input). Master Clear (Reset) input. This pin is an active low RESET to the device. Programming voltage input. -- These pins should be left unconnected. Oscillator crystal or external clock input. ST Oscillator crystal input or external clock source input. ST buffer when configured in RC mode, CMOS otherwise. CMOS External clock source input. Always associated with pin function OSC1. (See related OSC1/CLKIN, OSC2/CLKOUT pins.) Oscillator crystal output. -- Oscillator crystal output. Connects to crystal or resonator in Crystal Oscillator mode. -- In RC mode, OSC2 pin outputs CLKOUT, which has 1/4 the frequency of OSC1 and denotes the instruction cycle rate. TTL General Purpose I/O pin. PORTA is a bi-directional I/O port. ST
RA0/AN0 2 3 19 RA0 I/O TTL Digital I/O. AN0 I Analog Analog input 0. RA1/AN1 3 4 20 RA1 I/O TTL Digital I/O. AN1 I Analog Analog input 1. 4 5 21 RA2/AN2/VREFI/O TTL Digital I/O. RA2 I Analog Analog input 2. AN2 I Analog A/D Reference Voltage (Low) input. VREF5 6 22 RA3/AN3/VREF+ I/O TTL Digital I/O. RA3 I Analog Analog input 3. AN3 I Analog A/D Reference Voltage (High) input. VREF+ RA4/T0CKI 6 7 23 RA4 I/O ST/OD Digital I/O. Open drain when configured as output. T0CKI I ST Timer0 external clock input. RA5/AN4/SS/LVDIN 7 8 24 RA5 I/O TTL Digital I/O. AN4 I Analog Analog input 4. SS I ST SPI Slave Select input. LVDIN I Analog Low Voltage Detect Input. RA6 See the OSC2/CLKO/RA6 pin. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels I = Input O = Output P = Power OD = Open Drain (no P diode to VDD)
2001 Microchip Technology Inc.
DS39026C-page 13
PIC18CXX2
TABLE 1-3:
Pin Name DIP
PIC18C4X2 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number Pin Type PLCC TQFP Buffer Type Description PORTB is a bi-directional I/O port. PORTB can be software programmed for internal weak pull-ups on all inputs.
RB0/INT0 RB0 INT0 RB1/INT1 RB1 INT1 RB2/INT2 RB2 INT2 RB3/CCP2 RB3 CCP2 RB4 RB5 RB6
33
36
8 I/O I TTL ST TTL ST TTL ST Digital I/O. External Interrupt 0.
34
37
9 I/O I External Interrupt 1. Digital I/O. External Interrupt 2.
35
38
10 I/O I
36
39
11 I/O I/O I/O I/O I/O I I/O I/O
TTL Digital I/O. ST Capture2 input, Compare2 output, PWM2 output. 37 41 14 TTL Digital I/O. Interrupt-on-change pin. 38 42 15 TTL Digital I/O. Interrupt-on-change pin. 39 43 16 TTL Digital I/O. Interrupt-on-change pin. ST ICSP programming clock. RB7 40 44 17 TTL Digital I/O. Interrupt-on-change pin. ST ICSP programming data. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels I = Input O = Output P = Power OD = Open Drain (no P diode to VDD)
DS39026C-page 14
2001 Microchip Technology Inc.
PIC18CXX2
TABLE 1-3:
Pin Name DIP RC0/T1OSO/T1CKI RC0 T1OSO T1CKI RC1/T1OSI/CCP2 RC1 T1OSI CCP2 RC2/CCP1 RC2 CCP1 RC3/SCK/SCL RC3 SCK SCL 15
PIC18C4X2 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number Pin Type PLCC TQFP 16 32 I/O O I 16 18 35 I/O I I/O 17 19 36 I/O I/O 18 20 37 I/O I/O I/O ST ST ST Digital I/O. Synchronous serial clock input/output for SPI mode. Synchronous serial clock input/output for I2C mode. ST ST Digital I/O. Capture1 input/Compare1 output/PWM1 output. ST CMOS ST Digital I/O. Timer1 oscillator input. Capture2 input, Compare2 output, PWM2 output. ST -- ST Digital I/O. Timer1 oscillator output. Timer1/Timer3 external clock input. Buffer Type Description PORTC is a bi-directional I/O port.
RC4/SDI/SDA 23 25 42 RC4 I/O ST Digital I/O. SDI I ST SPI Data In. SDA I/O ST I2C Data I/O. RC5/SDO 24 26 43 RC5 I/O ST Digital I/O. SDO O -- SPI Data Out. RC6/TX/CK 25 27 44 RC6 I/O ST Digital I/O. TX O -- USART Asynchronous Transmit. CK I/O ST USART Synchronous Clock (see related RX/DT). RC7/RX/DT 26 29 1 I/O RC7 ST Digital I/O. RX I ST USART Asynchronous Receive. DT I/O ST USART Synchronous Data (see related TX/CK). Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels I = Input O = Output P = Power OD = Open Drain (no P diode to VDD)
2001 Microchip Technology Inc.
DS39026C-page 15
PIC18CXX2
TABLE 1-3:
Pin Name DIP
PIC18C4X2 PINOUT I/O DESCRIPTIONS (CONTINUED)
Pin Number Pin Type PLCC TQFP Buffer Type Description PORTD is a bi-directional I/O port, or a Parallel Slave Port (PSP) for interfacing to a microprocessor port. These pins have TTL input buffers when PSP module is enabled. Digital I/O. Parallel Slave Port Data. Digital I/O. Parallel Slave Port Data. Digital I/O. Parallel Slave Port Data. Digital I/O. Parallel Slave Port Data. Digital I/O. Parallel Slave Port Data. Digital I/O. Parallel Slave Port Data. Digital I/O. Parallel Slave Port Data. Digital I/O. Parallel Slave Port Data. PORTE is a bi-directional I/O port. Digital I/O. Read control for parallel slave port (see also WR and CS pins). Analog input 5. Digital I/O. Write control for parallel slave port (see CS and RD pins). Analog input 6.
RD0/PSP0 RD1/PSP1 RD2/PSP2 RD3/PSP3 RD4/PSP4 RD5/PSP5 RD6/PSP6 RD7/PSP7
19 20 21 22 27 28 29 30
21 22 23 24 30 31 32 33
38 39 40 41 2 3 4 5
I/O I/O I/O I/O I/O I/O I/O I/O
ST TTL ST TTL ST TTL ST TTL ST TTL ST TTL ST TTL ST TTL
RE0/RD/AN5 RE0 RD AN5 RE1/WR/AN6 RE1 WR AN6 RE2/CS/AN7 RE2 CS
8
9
25
I/O ST TTL Analog
9
10
26
I/O ST TTL Analog
10
11
27
I/O ST TTL
Digital I/O. Chip Select control for parallel slave port (see related RD and WR). AN7 Analog Analog input 7. 12, 31 13, 34 6, 29 P -- Ground reference for logic and I/O pins. VSS VDD 11, 32 12, 35 7, 28 P -- Positive supply for logic and I/O pins. Legend: TTL = TTL compatible input CMOS = CMOS compatible input or output ST = Schmitt Trigger input with CMOS levels I = Input O = Output P = Power OD = Open Drain (no P diode to VDD)
DS39026C-page 16
2001 Microchip Technology Inc.
PIC18CXX2
2.0
2.1
OSCILLATOR CONFIGURATIONS
Oscillator Types
TABLE 2-1:
CAPACITOR SELECTION FOR CERAMIC RESONATORS
Ranges Tested:
The PIC18CXX2 can be operated in eight different oscillator modes. The user can program three configuration bits (FOSC2, FOSC1, and FOSC0) to select one of these eight modes: 1. 2. 3. 4. 5. 6. 7. 8. LP XT HS HS + PLL RC RCIO EC ECIO Low Power Crystal Crystal/Resonator High Speed Crystal/Resonator High Speed Crystal/Resonator with x 4 PLL enabled External Resistor/Capacitor External Resistor/Capacitor with RA6 I/O pin enabled External Clock External Clock with RA6 I/O pin enabled
Mode XT
Freq
C1
C2
455 kHz 68 - 100 pF 68 - 100 pF 2.0 MHz 15 - 68 pF 15 - 68 pF 4.0 MHz 15 - 68 pF 15 - 68 pF HS 8.0 MHz 10 - 68 pF 10 - 68 pF 16.0 MHz 10 - 22 pF 10 - 22 pF These values are for design guidance only. See notes following this table. Resonators Used: 455 kHz Panasonic EFO-A455K04B 0.3% 2.0 MHz Murata Erie CSA2.00MG 0.5% 4.0 MHz Murata Erie CSA4.00MG 0.5% 8.0 MHz Murata Erie CSA8.00MT 0.5% 16.0 MHz Murata Erie CSA16.00MX 0.5% All resonators used did not have built-in capacitors.
2.2
Crystal Oscillator/Ceramic Resonators
In XT, LP, HS or HS-PLL oscillator modes, a crystal or ceramic resonator is connected to the OSC1 and OSC2 pins to establish oscillation. Figure 2-1 shows the pin connections. The PIC18CXX2 oscillator design requires the use of a parallel cut crystal. Note: Use of a series cut crystal may give a frequency out of the crystal manufacturers specifications.
Note 1: Higher capacitance increases the stability of the oscillator, but also increases the start-up time. 2: When operating below 3V VDD, it may be necessary to use high gain HS mode on lower frequency ceramic resonators. 3: Since each resonator/crystal has its own characteristics, the user should consult the resonator/crystal manufacturer for appropriate values of external components or verify oscillator performance.
FIGURE 2-1:
CRYSTAL/CERAMIC RESONATOR OPERATION (HS, XT OR LP OSC CONFIGURATION)
OSC1 To Internal Logic SLEEP
C1(1)
XTAL
RS(2) C2(1) OSC2
RF(3)
PIC18CXXX
Note 1: See Table 2-1 and Table 2-2 for recommended values of C1 and C2. 2: A series resistor (RS) may be required for AT strip cut crystals. 3: RF varies with the osc mode chosen.
2001 Microchip Technology Inc.
DS39026C-page 17
PIC18CXX2
TABLE 2-2: CAPACITOR SELECTION FOR CRYSTAL OSCILLATORS
Ranges Tested: Mode LP XT Freq 32.0 kHz 200 kHz 200 kHz 1.0 MHz 4.0 MHz HS 4.0 MHz 8.0 MHz 20.0 MHz 25.0 MHz C1 33 pF 15 pF 47-68 pF 15 pF 15 pF 15 pF 15-33 pF 15-33 pF 15-33 pF C2 33 pF 15 pF 47-68 pF 15 pF 15 pF 15 pF 15-33 pF 15-33 pF 15-33 pF
Clock from Ext. System Open
FIGURE 2-2:
EXTERNAL CLOCK INPUT OPERATION (HS, XT OR LP CONFIGURATION)
OSC1
PIC18CXXX
OSC2
2.3
RC Oscillator
These values are for design guidance only. See notes following this table. Crystals Used 32.0 kHz 200 kHz 1.0 MHz 4.0 MHz 8.0 MHz 20.0 MHz Epson C-001R32.768K-A STD XTL 200.000kHz ECS ECS-10-13-1 ECS ECS-40-20-1 Epson CA-301 8.000M-C 20 PPM 20 PPM 50 PPM 50 PPM 30 PPM
For timing insensitive applications, the "RC" and "RCIO" device options offer additional cost savings. The RC oscillator frequency is a function of the supply voltage, the resistor (REXT) and capacitor (CEXT) values and the operating temperature. In addition to this, the oscillator frequency will vary from unit to unit due to normal process parameter variation. Furthermore, the difference in lead frame capacitance between package types will also affect the oscillation frequency, especially for low CEXT values. The user also needs to take into account variation due to tolerance of external R and C components used. Figure 2-3 shows how the R/C combination is connected. In the RC oscillator mode, the oscillator frequency divided by 4 is available on the OSC2 pin. This signal may be used for test purposes or to synchronize other logic.
Epson CA-301 20.000M-C 30 PPM
FIGURE 2-3:
Note 1: Higher capacitance increases the stability of the oscillator, but also increases the start-up time. 2: Rs may be required in HS mode, as well as XT mode, to avoid overdriving crystals with low drive level specification. 3: Since each resonator/crystal has its own characteristics, the user should consult the resonator/crystal manufacturer for appropriate values of external components or verify oscillator performance. An external clock source may also be connected to the OSC1 pin in these modes, as shown in Figure 2-2.
VDD REXT
RC OSCILLATOR MODE
OSC1 CEXT VSS FOSC/4 OSC2/CLKO
Internal Clock
PIC18CXXX
Recommended values:3 k REXT 100 k CEXT > 20pF
The RCIO oscillator mode functions like the RC mode, except that the OSC2 pin becomes an additional general purpose I/O pin. The I/O pin becomes bit 6 of PORTA (RA6).
DS39026C-page 18
2001 Microchip Technology Inc.
PIC18CXX2
2.4 External Clock Input
FIGURE 2-5:
The EC and ECIO oscillator modes require an external clock source to be connected to the OSC1 pin. The feedback device between OSC1 and OSC2 is turned off in these modes to save current. There is no oscillator start-up time required after a Power-on Reset or after a recovery from SLEEP mode. In the EC oscillator mode, the oscillator frequency divided by 4 is available on the OSC2 pin. This signal may be used for test purposes or to synchronize other logic. Figure 2-4 shows the pin connections for the EC oscillator mode.
EXTERNAL CLOCK INPUT OPERATION (ECIO CONFIGURATION)
OSC1
Clock from Ext. System RA6
PIC18CXXX
I/O (OSC2)
2.5
HS/PLL
FIGURE 2-4:
EXTERNAL CLOCK INPUT OPERATION (EC OSC CONFIGURATION)
OSC1
A Phase Locked Loop circuit is provided as a programmable option for users that want to multiply the frequency of the incoming crystal oscillator signal by 4. For an input clock frequency of 10 MHz, the internal clock frequency will be multiplied to 40 MHz. This is useful for customers who are concerned with EMI due to high frequency crystals. The PLL can only be enabled when the oscillator configuration bits are programmed for HS mode. If they are programmed for any other mode, the PLL is not enabled and the system clock will come directly from OSC1. The PLL is one of the modes of the FOSC<2:0> configuration bits. The oscillator mode is specified during device programming. A PLL lock timer is used to ensure that the PLL has locked before device execution starts. The PLL lock timer has a time-out that is called TPLL.
Clock from Ext. System FOSC/4
PIC18CXXX
OSC2
The ECIO oscillator mode functions like the EC mode, except that the OSC2 pin becomes an additional general purpose I/O pin. The I/O pin becomes bit 6 of PORTA (RA6). Figure 2-5 shows the pin connections for the ECIO oscillator mode.
FIGURE 2-6:
(from Configuration bit Register)
PLL BLOCK DIAGRAM
HS Osc PLL Enable
OSC2 FIN Crystal Osc
Phase Comparator Loop Filter FOUT VCO SYSCLK Divide by 4 MUX DS39026C-page 19
OSC1
2001 Microchip Technology Inc.
PIC18CXX2
2.6 Oscillator Switching Feature
The PIC18CXX2 devices include a feature that allows the system clock source to be switched from the main oscillator to an alternate low frequency clock source. For the PIC18CXX2 devices, this alternate clock source is the Timer1 oscillator. If a low frequency crystal (32 kHz, for example) has been attached to the Timer1 oscillator pins and the Timer1 oscillator has been enabled, the device can switch to a low power execution mode. Figure 2-7 shows a block diagram of the system clock sources. The clock switching feature is enabled by programming the Oscillator Switching Enable (OSCSEN) bit in Configuration Register1H to a '0'. Clock switching is disabled in an erased device. See Section 9.0 for further details of the Timer1 oscillator. See Section 18.0 for Configuration Register details.
FIGURE 2-7:
DEVICE CLOCK SOURCES
PIC18CXXX
Main Oscillator OSC2 SLEEP OSC1 Timer1 Oscillator T1OSO T1OSCEN Enable Oscillator Clock Source option for other modules 4 x PLL TOSC TT1P TOSC/4 TSCLK
T1OSI
Clock Source
MUX
2.6.1
SYSTEM CLOCK SWITCH BIT
Note: The Timer1 oscillator must be enabled and operating to switch the system clock source. The Timer1 oscillator is enabled by setting the T1OSCEN bit in the Timer1 control register (T1CON). If the Timer1 oscillator is not enabled, then any write to the SCS bit will be ignored (SCS bit forced cleared) and the main oscillator will continue to be the system clock source.
The system clock source switching is performed under software control. The system clock switch bit, SCS (OSCCON<0>) controls the clock switching. When the SCS bit is'0', the system clock source comes from the main oscillator that is selected by the FOSC configuration bits in Configuration Register1H. When the SCS bit is set, the system clock source will come from the Timer1 oscillator. The SCS bit is cleared on all forms of RESET.
REGISTER 2-1:
OSCCON REGISTER
U-0 -- bit 7 U-0 -- U-0 -- U-0 -- U-0 -- U-0 -- U-0 -- R/W-1 SCS bit 0
bit 7-1 bit 0
Unimplemented: Read as '0' SCS: System Clock Switch bit When OSCSEN configuration bit = '0' and T1OSCEN bit is set: 1 = Switch to Timer1 oscillator/clock pin 0 = Use primary oscillator/clock input pin When OSCSEN and T1OSCEN are in other states: bit is forced clear Legend: R = Readable bit - n = Value at POR reset W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown
DS39026C-page 20
2001 Microchip Technology Inc.
PIC18CXX2
2.6.2 OSCILLATOR TRANSITIONS
The PIC18CXX2 devices contain circuitry to prevent "glitches" when switching between oscillator sources. Essentially, the circuitry waits for eight rising edges of the clock source that the processor is switching to. This ensures that the new clock source is stable and that it's pulse width will not be less than the shortest pulse width of the two clock sources. A timing diagram indicating the transition from the main oscillator to the Timer1 oscillator is shown in Figure 2-8. The Timer1 oscillator is assumed to be running all the time. After the SCS bit is set, the processor is frozen at the next occurring Q1 cycle. After eight synchronization cycles are counted from the Timer1 oscillator, operation resumes. No additional delays are required after the synchronization cycles.
FIGURE 2-8:
TIMING DIAGRAM FOR TRANSITION FROM OSC1 TO TIMER1 OSCILLATOR
Q1 Q2
Q3 Q4
Q1 TT1P 1 2 3 4 Tscs 5 6 7 8
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
Q1
T1OSI OSC1 TOSC Internal System Clock SCS (OSCCON<0>) Program Counter PC TDLY
PC + 2
PC + 4
Note 1: Delay on internal system clock is eight oscillator cycles for synchronization.
The sequence of events that takes place when switching from the Timer1 oscillator to the main oscillator will depend on the mode of the main oscillator. In addition to eight clock cycles of the main oscillator, additional delays may take place.
If the main oscillator is configured for an external crystal (HS, XT, LP), then the transition will take place after an oscillator start-up time (TOST) has occurred. A timing diagram indicating the transition from the Timer1 oscillator to the main oscillator for HS, XT and LP modes is shown in Figure 2-9.
FIGURE 2-9:
Q3
TIMING FOR TRANSITION BETWEEN TIMER1 AND OSC1 (HS, XT, LP)
Q4 Q1 TT1P Q1 Q2 Q3 Q4 Q1 Q2 Q3
T1OSI OSC1 TOST OSC2 Internal System Clock SCS (OSCCON<0>) TOSC 1 2 3 4 5 TSCS 6 7 8
Program Counter
PC
PC + 2
PC + 6
Note 1: TOST = 1024TOSC (drawing not to scale).
2001 Microchip Technology Inc.
DS39026C-page 21
PIC18CXX2
If the main oscillator is configured for HS-PLL mode, an oscillator start-up time (TOST) plus an additional PLL time-out (TPLL) will occur. The PLL time-out is typically 2 ms and allows the PLL to lock to the main oscillator frequency. A timing diagram, indicating the transition from the Timer1 oscillator to the main oscillator for HS-PLL mode, is shown in Figure 2-10.
FIGURE 2-10:
Q4
TIMING FOR TRANSITION BETWEEN TIMER1 AND OSC1 (HS WITH PLL)
Q1 TT1P Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
T1OSI OSC1 TOST OSC2 PLL Clock Input Internal System Clock SCS (OSCCON<0>) Program Counter PC PC + 2 PC + 4 TOSC
1 2 3
TPLL
TSCS
4 5 6 7 8
Note 1: TOST = 1024TOSC (drawing not to scale).
If the main oscillator is configured in the RC, RCIO, EC or ECIO modes, there is no oscillator start-up time-out. Operation will resume after eight cycles of the main oscillator have been counted. A timing diagram, indi-
cating the transition from the Timer1 oscillator to the main oscillator for RC, RCIO, EC and ECIO modes, is shown in Figure 2-11.
FIGURE 2-11:
Q3
TIMING FOR TRANSITION BETWEEN TIMER1 AND OSC1 (RC, EC)
Q4 Q1 TT1P Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
T1OSI OSC1 OSC2 Internal System Clock SCS (OSCCON<0>)
TOSC 1 2 3 4 5 6 7 8
TSCS Program Counter PC PC + 2 PC + 4
Note 1: RC oscillator mode assumed.
DS39026C-page 22
2001 Microchip Technology Inc.
PIC18CXX2
2.7 Effects of SLEEP Mode on the On-chip Oscillator
switching currents have been removed, SLEEP mode achieves the lowest current consumption of the device (only leakage currents). Enabling any on-chip feature that will operate during SLEEP will increase the current consumed during SLEEP. The user can wake from SLEEP through external RESET, Watchdog Timer Reset, or through an interrupt.
When the device executes a SLEEP instruction, the on-chip clocks and oscillator are turned off and the device is held at the beginning of an instruction cycle (Q1 state). With the oscillator off, the OSC1 and OSC2 signals will stop oscillating. Since all the transistor
TABLE 2-3:
OSC1 AND OSC2 PIN STATES IN SLEEP MODE
OSC1 Pin OSC2 Pin
OSC Mode RC
Note:
Floating, external resistor should At logic low pull high RCIO Floating, external resistor should Configured as PORTA, bit 6 pull high ECIO Floating Configured as PORTA, bit 6 EC Floating At logic low LP, XT, and HS Feedback inverter disabled, at Feedback inverter disabled, at quiescent voltage level quiescent voltage level See Table 3-1, in Section 3.0 RESET, for time-outs due to SLEEP and MCLR Reset.
2.8
Power-up Delays
Power up delays are controlled by two timers, so that no external RESET circuitry is required for most applications. The delays ensure that the device is kept in RESET until the device power supply and clock are stable. For additional information on RESET operation, see the "RESET" section. The first timer is the Power-up Timer (PWRT), which optionally provides a fixed delay of 72 ms (nominal) on power-up only (POR and BOR). The second timer is the Oscillator Start-up Timer, OST, intended to keep the chip in RESET until the crystal oscillator is stable.
With the PLL enabled (HS/PLL oscillator mode), the time-out sequence following a Power-on Reset is different from other oscillator modes. The time-out sequence is as follows: First, the PWRT time-out is invoked after a POR time delay has expired. Then, the Oscillator Start-up Timer (OST) is invoked. However, this is still not a sufficient amount of time to allow the PLL to lock at high frequencies. The PWRT timer is used to provide an additional fixed 2ms (nominal) time-out to allow the PLL ample time to lock to the incoming clock frequency.
2001 Microchip Technology Inc.
DS39026C-page 23
PIC18CXX2
NOTES:
DS39026C-page 24
2001 Microchip Technology Inc.
PIC18CXX2
3.0 RESET
The PIC18CXX2 differentiates between various kinds of RESET: a) b) c) d) e) f) g) h) Power-on Reset (POR) MCLR Reset during normal operation MCLR Reset during SLEEP Watchdog Timer (WDT) Reset (during normal operation) Programmable Brown-out Reset (BOR) RESET Instruction Stack Full Reset Stack Underflow Reset Most registers are not affected by a WDT wake-up, since this is viewed as the resumption of normal operation. Status bits from the RCON register, RI, TO, PD, POR and BOR, are set or cleared differently in different RESET situations, as indicated in Table 3-2. These bits are used in software to determine the nature of the RESET. See Table 3-3 for a full description of the RESET states of all registers. A simplified block diagram of the On-Chip Reset Circuit is shown in Figure 3-1. The Enhanced MCU devices have a MCLR noise filter in the MCLR Reset path. The filter will detect and ignore small pulses. MCLR pin is not driven low by any internal RESETS, including WDT.
Most registers are unaffected by a RESET. Their status is unknown on POR and unchanged by all other RESETS. The other registers are forced to a "RESET state" on Power-on Reset, MCLR, WDT Reset, Brownout Reset, MCLR Reset during SLEEP, and by the RESET instruction.
FIGURE 3-1:
RESET Instruction
SIMPLIFIED BLOCK DIAGRAM OF ON-CHIP RESET CIRCUIT
Stack Pointer
Stack Full/Underflow Reset External Reset
MCLR WDT Module VDD Rise Detect VDD Brown-out Reset OST/PWRT
SLEEP WDT Time-out Reset Power-on Reset S
BOREN
OST 10-bit Ripple Counter OSC1 PWRT On-chip RC OSC(1) 10-bit Ripple Counter R Q
Chip_Reset
Enable PWRT Enable OST(2) Note 1: This is a separate oscillator from the RC oscillator of the CLKIN pin. 2: See Table 3-1 for time-out situations.
2001 Microchip Technology Inc.
DS39026C-page 25
PIC18CXX2
3.1 Power-on Reset (POR) 3.3 Oscillator Start-up Timer (OST)
A Power-on Reset pulse is generated on-chip when VDD rise is detected. To take advantage of the POR circuitry, just tie the MCLR pin directly (or through a resistor) to VDD. This will eliminate external RC components usually needed to create a Power-on Reset delay. A minimum rise rate for VDD is specified (parameter D004). For a slow rise time, see Figure 3-2. When the device starts normal operation (i.e., exits the RESET condition), device operating parameters (voltage, frequency, temperature, etc.) must be met to ensure operation. If these conditions are not met, the device must be held in reset until the operating conditions are met. The Oscillator Start-up Timer (OST) provides a 1024 oscillator cycle (from OSC1 input) delay after the PWRT delay is over (parameter #32). This ensures that the crystal oscillator or resonator has started and stabilized. The OST time-out is invoked only for XT, LP and HS modes and only on Power-on Reset or wake-up from SLEEP.
3.4
PLL Lock Time-out
FIGURE 3-2:
EXTERNAL POWER-ON RESET CIRCUIT (FOR SLOW VDD POWER-UP)
VDD
With the PLL enabled, the time-out sequence following a Power-on Reset is different from other oscillator modes. A portion of the Power-up Timer is used to provide a fixed time-out that is sufficient for the PLL to lock to the main oscillator frequency. This PLL lock time-out (TPLL) is typically 2 ms and follows the oscillator startup time-out (OST).
3.5
Brown-out Reset (BOR)
D
R R1 MCLR C
PIC18CXXX
Note 1: External Power-on Reset circuit is required only if the VDD power-up slope is too slow. The diode D helps discharge the capacitor quickly when VDD powers down. 2: R < 40 k is recommended to make sure that the voltage drop across R does not violate the device's electrical specification. 3: R1 = 100 to 1 k will limit any current flowing into MCLR from external capacitor C in the event of MCLR/VPP pin breakdown, due to Electrostatic Discharge (ESD) or Electrical Overstress (EOS).
A configuration bit, BOREN, can disable (if clear/ programmed), or enable (if set) the Brown-out Reset circuitry. If VDD falls below parameter D005 for greater than parameter #35, the brown-out situation will reset the chip. A RESET may not occur if VDD falls below parameter D005 for less than parameter #35. The chip will remain in Brown-out Reset until VDD rises above BVDD. The Power-up Timer will then be invoked and will keep the chip in RESET an additional time delay (parameter #33). If VDD drops below BVDD while the Power-up Timer is running, the chip will go back into a Brown-out Reset and the Power-up Timer will be initialized. Once VDD rises above BVDD, the Power-up Timer will execute the additional time delay.
3.6
Time-out Sequence
3.2
Power-up Timer (PWRT)
The Power-up Timer provides a fixed nominal time-out (parameter #33) only on power-up from the POR. The Power-up Timer operates on an internal RC oscillator. The chip is kept in reset as long as the PWRT is active. The PWRT's time delay allows VDD to rise to an acceptable level. A configuration bit is provided to enable/ disable the PWRT. The power-up time delay will vary from chip-to-chip due to VDD, temperature and process variation. See DC parameter #33 for details.
On power-up, the time-out sequence is as follows: First, PWRT time-out is invoked after the POR time delay has expired. Then, OST is activated. The total time-out will vary based on oscillator configuration and the status of the PWRT. For example, in RC mode with the PWRT disabled, there will be no time-out at all. Figure 3-3, Figure 3-4, Figure 3-5, Figure 3-6 and Figure 3-7 depict time-out sequences on power-up. Since the time-outs occur from the POR pulse, if MCLR is kept low long enough, the time-outs will expire. Bringing MCLR high will begin execution immediately (Figure 3-5). This is useful for testing purposes or to synchronize more than one PIC18CXXX device operating in parallel. Table 3-2 shows the RESET conditions for some Special Function Registers, while Table 3-3 shows the RESET conditions for all the registers.
DS39026C-page 26
2001 Microchip Technology Inc.
PIC18CXX2
TABLE 3-1: TIME-OUT IN VARIOUS SITUATIONS
Power-up(2) Brown-out(2) PWRTE = 0 PWRTE = 1 72 ms + 1024TOSC + 2ms 72 ms + 1024TOSC 72 ms 72 ms Wake-up from SLEEP or Oscillator Switch 1024TOSC + 2 ms 1024TOSC -- -- Oscillator Configuration HS with PLL enabled(1)
72 ms + 1024TOSC 1024TOSC + 2ms + 2 ms HS, XT, LP 72 ms + 1024TOSC 1024TOSC EC 72 ms -- External RC 72 ms -- Note 1: 2 ms is the nominal time required for the 4x PLL to lock. 2: 72 ms is the nominal Power-up Timer delay.
REGISTER 3-1:
RCON REGISTER BITS AND POSITIONS
R/W-0 IPEN bit 7 Note: See Register 4-3 on page 53 for bit definitions. R/W-0 LWRT U-0 -- R/W-1 RI R/W-1 TO R/W-1 PD R/W-0 POR R/W-0 BOR bit 0
TABLE 3-2:
STATUS BITS, THEIR SIGNIFICANCE AND THE INITIALIZATION CONDITION FOR RCON REGISTER
Program Counter 0000h 0000h 0000h 0000h 0000h 0000h 0000h PC + 2 0000h PC + 2(1) RCON Register 00-1 1100 00-u uuuu 0u-0 uuuu 0u-u uu11 0u-u uu11 00-u 10uu 0u-u 01uu uu-u 00uu 0u-1 11u0 uu-u 00uu RI 1 u 0 u u u 1 u 1 u TO 1 u u u u 1 0 0 1 1 PD 1 u u u u 0 1 0 1 0 POR 0 u u u u u u u 1 u BOR 0 u u u u u u u 0 u STKFUL u u u u 1 u u u u u STKUNF u u u 1 u u u u u u
Condition Power-on Reset MCLR Reset during normal operation Software Reset during normal operation Stack Full Reset during normal operation Stack Underflow Reset during normal operation MCLR Reset during SLEEP WDT Reset WDT Wake-up Brown-out Reset Interrupt wake-up from SLEEP
Legend: u = unchanged, x = unknown, - = unimplemented bit, read as '0'. Note 1: When the wake-up is due to an interrupt and the GIEH or GIEL bits are set, the PC is loaded with the interrupt vector (0x000008h or 0x000018h).
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PIC18CXX2
TABLE 3-3: INITIALIZATION CONDITIONS FOR ALL REGISTERS
Power-on Reset, Brown-out Reset MCLR Resets WDT Reset RESET Instruction Stack Resets Wake-up via WDT or Interrupt
Register
Applicable Devices
TOSU 242 442 252 452 ---0 0000 ---0 0000 ---0 uuuu(3) TOSH 242 442 252 452 0000 0000 0000 0000 uuuu uuuu(3) TOSL 242 442 252 452 0000 0000 0000 0000 uuuu uuuu(3) STKPTR 242 442 252 452 00-0 0000 00-0 0000 uu-u uuuu(3) PCLATU 242 442 252 452 ---0 0000 ---0 0000 ---u uuuu PCLATH 242 442 252 452 0000 0000 0000 0000 uuuu uuuu PCL 242 442 252 452 0000 0000 0000 0000 PC + 2(2) TBLPTRU 242 442 252 452 --00 0000 --00 0000 --uu uuuu TBLPTRH 242 442 252 452 0000 0000 0000 0000 uuuu uuuu TBLPTRL 242 442 252 452 0000 0000 0000 0000 uuuu uuuu TABLAT 242 442 252 452 0000 0000 0000 0000 uuuu uuuu PRODH 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu PRODL 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu INTCON 242 442 252 452 0000 000x 0000 000u uuuu uuuu(1) INTCON2 242 442 252 452 1111 -1-1 1111 -1-1 uuuu -u-u(1) INTCON3 242 442 252 452 11-0 0-00 11-0 0-00 uu-u u-uu(1) INDF0 242 442 252 452 N/A N/A N/A POSTINC0 242 442 252 452 N/A N/A N/A POSTDEC0 242 442 252 452 N/A N/A N/A PREINC0 242 442 252 452 N/A N/A N/A PLUSW0 242 442 252 452 N/A N/A N/A FSR0H 242 442 252 452 ---- 0000 ---- 0000 ---- uuuu FSR0L 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu WREG 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu INDF1 242 442 252 452 N/A N/A N/A POSTINC1 242 442 252 452 N/A N/A N/A POSTDEC1 242 442 252 452 N/A N/A N/A PREINC1 242 442 252 452 N/A N/A N/A PLUSW1 242 442 252 452 N/A N/A N/A Legend: u = unchanged, x = unknown, - = unimplemented bit, read as '0', q = value depends on condition Note 1: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up). 2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt vector (0008h or 0018h). 3: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are updated with the current value of the PC. The STKPTR is modified to point to the next location in the hardware stack. 4: See Table 3-2 for RESET value for specific condition. 5: Bit 6 of PORTA, LATA, and TRISA are enabled in ECIO and RCIO oscillator modes only. In all other oscillator modes, they are disabled and read '0'. 6: The long write enable is only reset on a POR or MCLR Reset. 7: Bit 6 of PORTA, LATA and TRISA are not available on all devices. When unimplemented, they are read as '0'.
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PIC18CXX2
TABLE 3-3: INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED)
Power-on Reset, Brown-out Reset MCLR Resets WDT Reset RESET Instruction Stack Resets Wake-up via WDT or Interrupt
Register
Applicable Devices
FSR1H 242 442 252 452 ---- 0000 ---- 0000 ---- uuuu FSR1L 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu BSR 242 442 252 452 ---- 0000 ---- 0000 ---- uuuu INDF2 242 442 252 452 N/A N/A N/A POSTINC2 242 442 252 452 N/A N/A N/A POSTDEC2 242 442 252 452 N/A N/A N/A PREINC2 242 442 252 452 N/A N/A N/A PLUSW2 242 442 252 452 N/A N/A N/A FSR2H 242 442 252 452 ---- 0000 ---- 0000 ---- uuuu FSR2L 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu STATUS 242 442 252 452 ---x xxxx ---u uuuu ---u uuuu TMR0H 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu TMR0L 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu T0CON 242 442 252 452 1111 1111 1111 1111 uuuu uuuu OSCCON 242 442 252 452 ---- ---0 ---- ---0 ---- ---u LVDCON 242 442 252 452 --00 0101 --00 0101 --uu uuuu WDTCON 242 442 252 452 ---- ---0 ---- ---0 ---- ---u (4, 6) RCON 242 442 252 452 00-1 11q0 00-1 qquu uu-u qquu TMR1H 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu TMR1L 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu T1CON 242 442 252 452 0-00 0000 u-uu uuuu u-uu uuuu TMR2 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu PR2 242 442 252 452 1111 1111 1111 1111 1111 1111 T2CON 242 442 252 452 -000 0000 -000 0000 -uuu uuuu SSPBUF 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu SSPADD 242 442 252 452 0000 0000 0000 0000 uuuu uuuu SSPSTAT 242 442 252 452 0000 0000 0000 0000 uuuu uuuu SSPCON1 242 442 252 452 0000 0000 0000 0000 uuuu uuuu SSPCON2 242 442 252 452 0000 0000 0000 0000 uuuu uuuu Legend: u = unchanged, x = unknown, - = unimplemented bit, read as '0', q = value depends on condition Note 1: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up). 2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt vector (0008h or 0018h). 3: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are updated with the current value of the PC. The STKPTR is modified to point to the next location in the hardware stack. 4: See Table 3-2 for RESET value for specific condition. 5: Bit 6 of PORTA, LATA, and TRISA are enabled in ECIO and RCIO oscillator modes only. In all other oscillator modes, they are disabled and read '0'. 6: The long write enable is only reset on a POR or MCLR Reset. 7: Bit 6 of PORTA, LATA and TRISA are not available on all devices. When unimplemented, they are read as '0'.
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PIC18CXX2
TABLE 3-3: INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED)
Power-on Reset, Brown-out Reset MCLR Resets WDT Reset RESET Instruction Stack Resets Wake-up via WDT or Interrupt
Register
Applicable Devices
242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu 242 442 252 452 0000 0000 0000 0000 uuuu uuuu 242 442 252 452 --0- 0000 --0- 0000 --u- uuuu 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu 242 442 252 452 --00 0000 --00 0000 --uu uuuu 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu 242 442 252 452 --00 0000 --00 0000 --uu uuuu 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu 242 442 252 452 0000 0000 uuuu uuuu uuuu uuuu 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu 242 442 252 452 0000 -01x 0000 -01u uuuu -uuu 242 442 252 452 0000 000x 0000 000u uuuu uuuu 242 442 252 452 ---- 1111 ---- 1111 ---- uuuu 242 442 252 452 ---- 0000 ---- 0000 ---- uuuu(1) 242 442 252 452 ---- 0000 ---- 0000 ---- uuuu 242 442 252 452 1111 1111 1111 1111 uuuu uuuu 242 442 252 452 -111 1111 -111 1111 -uuu uuuu PIR1 242 442 252 452 0000 0000 0000 0000 uuuu uuuu(1) 242 442 252 452 -000 0000 -000 0000 -uuu uuuu(1) PIE1 242 442 252 452 0000 0000 0000 0000 uuuu uuuu 242 442 252 452 -000 0000 -000 0000 -uuu uuuu Legend: u = unchanged, x = unknown, - = unimplemented bit, read as '0', q = value depends on condition Note 1: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up). 2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt vector (0008h or 0018h). 3: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are updated with the current value of the PC. The STKPTR is modified to point to the next location in the hardware stack. 4: See Table 3-2 for RESET value for specific condition. 5: Bit 6 of PORTA, LATA, and TRISA are enabled in ECIO and RCIO oscillator modes only. In all other oscillator modes, they are disabled and read '0'. 6: The long write enable is only reset on a POR or MCLR Reset. 7: Bit 6 of PORTA, LATA and TRISA are not available on all devices. When unimplemented, they are read as '0'.
ADRESH ADRESL ADCON0 ADCON1 CCPR1H CCPR1L CCP1CON CCPR2H CCPR2L CCP2CON TMR3H TMR3L T3CON SPBRG RCREG TXREG TXSTA RCSTA IPR2 PIR2 PIE2 IPR1
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PIC18CXX2
TABLE 3-3: INITIALIZATION CONDITIONS FOR ALL REGISTERS (CONTINUED)
Power-on Reset, Brown-out Reset MCLR Resets WDT Reset RESET Instruction Stack Resets Wake-up via WDT or Interrupt
Register
Applicable Devices
TRISE 242 442 252 452 0000 -111 0000 -111 uuuu -uuu TRISD 242 442 252 452 1111 1111 1111 1111 uuuu uuuu TRISC 242 442 252 452 1111 1111 1111 1111 uuuu uuuu TRISB 242 442 252 452 1111 1111 1111 1111 uuuu uuuu TRISA(5, 7) 242 442 252 452 -111 1111(5) -111 1111(5) -uuu uuuu(5) LATE 242 442 252 452 ---- -xxx ---- -uuu ---- -uuu LATD 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu LATC 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu LATB 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu (5, 7) (5) (5) LATA 242 442 252 452 -xxx xxxx -uuu uuuu -uuu uuuu(5) PORTE 242 442 252 452 ---- -000 ---- -000 ---- -uuu PORTD 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu PORTC 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu PORTB 242 442 252 452 xxxx xxxx uuuu uuuu uuuu uuuu PORTA(5, 7) 242 442 252 452 -x0x 0000(5) -u0u 0000(5) -uuu uuuu(5) Legend: u = unchanged, x = unknown, - = unimplemented bit, read as '0', q = value depends on condition Note 1: One or more bits in the INTCONx or PIRx registers will be affected (to cause wake-up). 2: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the PC is loaded with the interrupt vector (0008h or 0018h). 3: When the wake-up is due to an interrupt and the GIEL or GIEH bit is set, the TOSU, TOSH and TOSL are updated with the current value of the PC. The STKPTR is modified to point to the next location in the hardware stack. 4: See Table 3-2 for RESET value for specific condition. 5: Bit 6 of PORTA, LATA, and TRISA are enabled in ECIO and RCIO oscillator modes only. In all other oscillator modes, they are disabled and read '0'. 6: The long write enable is only reset on a POR or MCLR Reset. 7: Bit 6 of PORTA, LATA and TRISA are not available on all devices. When unimplemented, they are read as '0'.
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PIC18CXX2
FIGURE 3-3:
VDD MCLR INTERNAL POR TPWRT PWRT TIME-OUT
TIME-OUT SEQUENCE ON POWER-UP (MCLR TIED TO VDD)
TOST
OST TIME-OUT
INTERNAL RESET
FIGURE 3-4:
TIME-OUT SEQUENCE ON POWER-UP (MCLR NOT TIED TO VDD): CASE 1
VDD MCLR INTERNAL POR TPWRT PWRT TIME-OUT
TOST
OST TIME-OUT
INTERNAL RESET
FIGURE 3-5:
TIME-OUT SEQUENCE ON POWER-UP (MCLR NOT TIED TO VDD): CASE 2
VDD MCLR INTERNAL POR TPWRT PWRT TIME-OUT
TOST
OST TIME-OUT
INTERNAL RESET
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PIC18CXX2
FIGURE 3-6: SLOW RISE TIME (MCLR TIED TO VDD)
5V VDD MCLR INTERNAL POR TPWRT PWRT TIME-OUT TOST OST TIME-OUT INTERNAL RESET 0V 1V
FIGURE 3-7:
TIME-OUT SEQUENCE ON POR W/ PLL ENABLED (MCLR TIED TO VDD)
VDD MCLR IINTERNAL POR TPWRT PWRT TIME-OUT
TOST TPLL
OST TIME-OUT
PLL TIME-OUT INTERNAL RESET
Note:
TOST = 1024 clock cycles. TPLL 2 ms max. First three stages of the PWRT timer.
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PIC18CXX2
NOTES:
DS39026C-page 34
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PIC18CXX2
4.0 MEMORY ORGANIZATION
There are two memory blocks in Enhanced MCU devices. These memory blocks are: * Program Memory * Data Memory Program and data memory use separate buses so that concurrent access can occur.
4.1
Program Memory Organization
A 21-bit program counter is capable of addressing the 2-Mbyte program memory space. Accessing a location between the physically implemented memory and the 2-Mbyte address will cause a read of all '0's (a NOP instruction). PIC18C252 and PIC18C452 have 32 Kbytes of EPROM, while PIC18C242 and PIC18C442 have 16 Kbytes of EPROM. This means that PIC18CX52 devices can store up to 16K of single word instructions, and PIC18CX42 devices can store up to 8K of single word instructions. The RESET vector address is at 0000h and the interrupt vector addresses are at 0008h and 0018h. Figure 4-1 shows the Program Memory Map for PIC18C242/442 devices and Figure 4-2 shows the Program Memory Map for PIC18C252/452 devices.
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PIC18CXX2
FIGURE 4-1: PROGRAM MEMORY MAP AND STACK FOR PIC18C442/242 FIGURE 4-2: PROGRAM MEMORY MAP AND STACK FOR PIC18C452/252
PC<20:0> 21 CALL,RCALL,RETURN RETFIE,RETLW Stack Level 1
* * *
PC<20:0> 21 CALL,RCALL,RETURN RETFIE,RETLW Stack Level 1
* * *
Stack Level 31
Stack Level 31 0000h
RESET Vector
RESET Vector
0000h
High Priority Interrupt Vector 0008h Low Priority Interrupt Vector 0018h On-chip Program Memory 3FFFh 4000h User Memory Space
High Priority Interrupt Vector 0008h Low Priority Interrupt Vector 0018h
7FFFh 8000h
Read '0'
Read '0'
1FFFFFh 200000h
1FFFFFh 200000h
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User Memory Space
On-chip Program Memory
PIC18CXX2
4.2 Return Address Stack
4.2.2
The return address stack allows any combination of up to 31 program calls and interrupts to occur. The PC (Program Counter) is pushed onto the stack when a CALL or RCALL instruction is executed, or an interrupt is acknowledged. The PC value is pulled off the stack on a RETURN, RETLW or a RETFIE instruction. PCLATU and PCLATH are not affected by any of the call or return instructions. The stack operates as a 31-word by 21-bit RAM and a 5-bit stack pointer, with the stack pointer initialized to 00000b after all RESETS. There is no RAM associated with stack pointer 00000b. This is only a RESET value. During a CALL type instruction causing a push onto the stack, the stack pointer is first incremented and the RAM location pointed to by the stack pointer is written with the contents of the PC. During a RETURN type instruction causing a pop from the stack, the contents of the RAM location pointed to by the STKPTR is transferred to the PC and then the stack pointer is decremented. The stack space is not part of either program or data space. The stack pointer is readable and writable, and the address on the top of the stack is readable and writable through SFR registers. Data can also be pushed to, or popped from, the stack, using the top-of-stack SFRs. Status bits indicate if the stack pointer is at, or beyond the 31 levels provided.
RETURN STACK POINTER (STKPTR)
The STKPTR register contains the stack pointer value, the STKFUL (stack full) status bit, and the STKUNF (stack underflow) status bits. Register 4-1 shows the STKPTR register. The value of the stack pointer can be 0 through 31. The stack pointer increments when values are pushed onto the stack and decrements when values are popped off the stack. At RESET, the stack pointer value will be 0. The user may read and write the stack pointer value. This feature can be used by a Real Time Operating System for return stack maintenance. After the PC is pushed onto the stack 31 times (without popping any values off the stack), the STKFUL bit is set. The STKFUL bit can only be cleared in software or by a POR. The action that takes place when the stack becomes full, depends on the state of the STVREN (Stack Overflow Reset Enable) configuration bit. Refer to Section 18.0 for a description of the device configuration bits. If STVREN is set (default), the 31st push will push the (PC + 2) value onto the stack, set the STKFUL bit, and reset the device. The STKFUL bit will remain set and the stack pointer will be set to 0. If STVREN is cleared, the STKFUL bit will be set on the 31st push and the stack pointer will increment to 31. Any additional pushes will not overwrite the 31st push and STKPTR will remain at 31. When the stack has been popped enough times to unload the stack, the next pop will return a value of zero to the PC and sets the STKUNF bit, while the stack pointer remains at 0. The STKUNF bit will remain set until cleared in software or a POR occurs. Note: Returning a value of zero to the PC on an underflow, has the effect of vectoring the program to the RESET vector, where the stack conditions can be verified and appropriate actions can be taken.
4.2.1
TOP-OF-STACK ACCESS
The top of the stack is readable and writable. Three register locations, TOSU, TOSH and TOSL hold the contents of the stack location pointed to by the STKPTR register. This allows users to implement a software stack, if necessary. After a CALL, RCALL or interrupt, the software can read the pushed value by reading the TOSU, TOSH and TOSL registers. These values can be placed on a user defined software stack. At return time, the software can replace the TOSU, TOSH and TOSL and do a return. The user must disable the global interrupt enable bits during this time to prevent inadvertent stack operations..
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PIC18CXX2
REGISTER 4-1: STKPTR REGISTER
R/C-0 STKFUL bit 7 bit 7(1) STKFUL: Stack Full Flag bit 1 = Stack became full or overflowed 0 = Stack has not become full or overflowed STKUNF: Stack Underflow Flag bit 1 = Stack underflow occurred 0 = Stack underflow did not occur Unimplemented: Read as '0' SP4:SP0: Stack Pointer Location bits Note 1: Bit 7 and bit 6 can only be cleared in user software or by a POR. Legend: R = Readable bit - n = Value at POR W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown R/C-0 STKUNF U-0 -- R/W-0 SP4 R/W-0 SP3 R/W-0 SP2 R/W-0 SP1 R/W-0 SP0 bit 0
bit 6(1)
bit 5 bit 4-0
FIGURE 4-3:
RETURN ADDRESS STACK AND ASSOCIATED REGISTERS
Return Address Stack 11111 11110 11101 TOSU 0x00 TOSH 0x1A TOSL 0x34 00011 Top-of-Stack 0x001A34 00010 0x000D58 00001 00000 STKPTR<4:0> 00010
4.2.3
PUSH AND POP INSTRUCTIONS
4.2.4
STACK FULL/UNDERFLOW RESETS
Since the Top-of-Stack (TOS) is readable and writable, the ability to push values onto the stack and pull values off the stack, without disturbing normal program execution, is a desirable option. To push the current PC value onto the stack, a PUSH instruction can be executed. This will increment the stack pointer and load the current PC value onto the stack. TOSU, TOSH and TOSL can then be modified to place a return address on the stack. The ability to pull the TOS value off of the stack and replace it with the value that was previously pushed onto the stack, without disturbing normal execution, is achieved by using the POP instruction. The POP instruction discards the current TOS by decrementing the stack pointer. The previous value pushed onto the stack then becomes the TOS value.
These resets are enabled by programming the STVREN configuration bit. When the STVREN bit is disabled, a full or underflow condition will set the appropriate STKFUL or STKUNF bit, but not cause a device RESET. When the STVREN bit is enabled, a full or underflow will set the appropriate STKFUL or STKUNF bit and then cause a device RESET. The STKFUL or STKUNF bits are only cleared by the user software or a POR Reset.
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PIC18CXX2
4.3 Fast Register Stack 4.4 PCL, PCLATH and PCLATU
A "fast interrupt return" option is available for interrupts. A Fast Register Stack is provided for the STATUS, WREG and BSR registers and are only one in depth. The stack is not readable or writable and is loaded with the current value of the corresponding register when the processor vectors for an interrupt. The values in the registers are then loaded back into the working registers, if the FAST RETURN instruction is used to return from the interrupt. A low or high priority interrupt source will push values into the stack registers. If both low and high priority interrupts are enabled, the stack registers cannot be used reliably for low priority interrupts. If a high priority interrupt occurs while servicing a low priority interrupt, the stack register values stored by the low priority interrupt will be overwritten. If high priority interrupts are not disabled during low priority interrupts, users must save the key registers in software during a low priority interrupt. If no interrupts are used, the fast register stack can be used to restore the STATUS, WREG and BSR registers at the end of a subroutine call. To use the fast register stack for a subroutine call, a FAST CALL instruction must be executed. Example 4-1 shows a source code example that uses the fast register stack. The program counter (PC) specifies the address of the instruction to fetch for execution. The PC is 21-bits wide. The low byte is called the PCL register. This register is readable and writable. The high byte is called the PCH register. This register contains the PC<15:8> bits and is not directly readable or writable. Updates to the PCH register may be performed through the PCLATH register. The upper byte is called PCU. This register contains the PC<20:16> bits and is not directly readable or writable. Updates to the PCU register may be performed through the PCLATU register. The PC addresses bytes in the program memory. To prevent the PC from becoming misaligned with word instructions, the LSB of PCL is fixed to a value of '0'. The PC increments by 2 to address sequential instructions in the program memory. The CALL, RCALL, GOTO and program branch instructions write to the program counter directly. For these instructions, the contents of PCLATH and PCLATU are not transferred to the program counter. The contents of PCLATH and PCLATU will be transferred to the program counter by an operation that writes PCL. Similarly, the upper two bytes of the program counter will be transferred to PCLATH and PCLATU by an operation that reads PCL. This is useful for computed offsets to the PC (see Section 4.8.1).
EXAMPLE 4-1:
CALL SUB1, FAST
FAST REGISTER STACK CODE EXAMPLE
;STATUS, WREG, BSR ;SAVED IN FAST REGISTER ;STACK
4.5
Clocking Scheme/Instruction Cycle
* *
SUB1
* * * RETURN FAST
;RESTORE VALUES SAVED ;IN FAST REGISTER STACK
The clock input (from OSC1) is internally divided by four to generate four non-overlapping quadrature clocks, namely Q1, Q2, Q3 and Q4. Internally, the program counter (PC) is incremented every Q1, the instruction is fetched from the program memory and latched into the instruction register in Q4. The instruction is decoded and executed during the following Q1 through Q4. The clocks and instruction execution flow is shown in Figure 4-4.
FIGURE 4-4:
CLOCK/INSTRUCTION CYCLE
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
OSC1 Q1 Q2 Q3 Q4 PC OSC2/CLKOUT (RC mode)
PC PC+2 PC+4 Internal Phase Clock
Execute INST (PC-2) Fetch INST (PC)
Execute INST (PC) Fetch INST (PC+2)
Execute INST (PC+2) Fetch INST (PC+4)
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DS39026C-page 39
PIC18CXX2
4.6 Instruction Flow/Pipelining
An "Instruction Cycle" consists of four Q cycles (Q1, Q2, Q3 and Q4). The instruction fetch and execute are pipelined such that fetch takes one instruction cycle, while decode and execute takes another instruction cycle. However, due to the pipelining, each instruction effectively executes in one cycle. If an instruction causes the program counter to change (e.g. GOTO), then two cycles are required to complete the instruction (Example 4-2). A fetch cycle begins with the program counter (PC) incrementing in Q1. In the execution cycle, the fetched instruction is latched into the "Instruction Register" (IR) in cycle Q1. This instruction is then decoded and executed during the Q2, Q3, and Q4 cycles. Data memory is read during Q2 (operand read) and written during Q4 (destination write).
EXAMPLE 4-2:
INSTRUCTION PIPELINE FLOW
TCY0 TCY1 Execute 1 Fetch 2 Execute 2 Fetch 3 Execute 3 Fetch 4 Flush (NOP) Fetch SUB_1 Execute SUB_1 TCY2 TCY3 TCY4 TCY5
1. MOVLW 55h 2. MOVWF PORTB 3. BRA 4. BSF SUB_1
Fetch 1
PORTA, BIT3 (Forced NOP)
5. Instruction @ address SUB_1
All instructions are single cycle, except for any program branches. These take two cycles since the fetch instruction is "flushed" from the pipeline, while the new instruction is being fetched and then executed.
4.7
Instructions in Program Memory
The program memory is addressed in bytes. Instructions are stored as two bytes or four bytes in program memory. The Least Significant Byte of an instruction word is always stored in a program memory location with an even address (LSB ='0'). Figure 4-5 shows an example of how instruction words are stored in the program memory. To maintain alignment with instruction boundaries, the PC increments in steps of 2 and the LSB will always read '0' (see Section 4.4).
The CALL and GOTO instructions have an absolute program memory address embedded into the instruction. Since instructions are always stored on word boundaries, the data contained in the instruction is a word address. The word address is written to PC<20:1>, which accesses the desired byte address in program memory. Instruction #2 in Figure 4-5 shows how the instruction "GOTO 000006h" is encoded in the program memory. Program branch instructions, which encode a relative address offset, operate in the same manner. The offset value stored in a branch instruction represents the number of single word instructions that the PC will be offset by. Section 19.0 provides further details of the instruction set.
FIGURE 4-5:
INSTRUCTIONS IN PROGRAM MEMORY
LSB = 1 Program Memory Byte Locations LSB = 0 Word Address 000000h 000002h 000004h 000006h 000008h 00000Ah 00000Ch 00000Eh 000010h 000012h 000014h
Instruction 1: Instruction 2: Instruction 3:
MOVLW GOTO MOVFF
055h 000006h 123h, 456h
0Fh EFh F0h C1h F4h
55h 03h 00h 23h 56h
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PIC18CXX2
4.7.1 TWO-WORD INSTRUCTIONS
The PIC18CXX2 devices have four two-word instructions: MOVFF, CALL, GOTO and LFSR. The second word of these instructions has the 4 MSBs set to 1's and is a special kind of NOP instruction. The lower 12bits of the second word contain data to be used by the instruction. If the first word of the instruction is executed, the data in the second word is accessed. If the second word of the instruction is executed by itself (first word was skipped), it will execute as a NOP. This action is necessary when the two-word instruction is preceded by a conditional instruction that changes the PC. A program example that demonstrates this concept is shown in Example 4-3. Refer to Section 19.0 for further details of the instruction set.
EXAMPLE 4-3:
CASE 1: Object Code
TWO-WORD INSTRUCTIONS
Source Code TSTFSZ MOVFF ADDWF REG1 ; is RAM location 0? ; 2nd operand holds address of REG2 REG3 ; continue code
0110 0110 0000 0000 1100 0001 0010 0011 1111 0100 0101 0110 0010 0100 0000 0000 CASE 2: Object Code 0110 0110 0000 0000 1100 0001 0010 0011 1111 0100 0101 0110 0010 0100 0000 0000
REG1, REG2 ; No, execute 2-word instruction
Source Code TSTFSZ MOVFF ADDWF REG1 ; is RAM location 0? ; 2nd operand becomes NOP REG3 ; continue code
REG1, REG2 ; Yes
4.8
Lookup Tables
4.8.2
TABLE READS/TABLE WRITES
Lookup tables are implemented two ways. These are: * Computed GOTO * Table Reads
A better method of storing data in program memory allows 2 bytes of data to be stored in each instruction location. Lookup table data may be stored 2 bytes per program word by using table reads and writes. The table pointer (TBLPTR) specifies the byte address and the table latch (TABLAT) contains the data that is read from, or written to program memory. Data is transferred to/from program memory one byte at a time. A description of the Table Read/Table Write operation is shown in Section 5.0.
4.8.1
COMPUTED GOTO
A computed GOTO is accomplished by adding an offset to the program counter (ADDWF PCL). A lookup table can be formed with an ADDWF PCL instruction and a group of RETLW 0xnn instructions. WREG is loaded with an offset into the table, before executing a call to that table. The first instruction of the called routine is the ADDWF PCL instruction. The next instruction executed will be one of the RETLW 0xnn instructions that returns the value 0xnn to the calling function. The offset value (value in WREG) specifies the number of bytes that the program counter should advance. In this method, only one data byte may be stored in each instruction location and room on the return address stack is required.
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PIC18CXX2
4.9 Data Memory Organization
4.9.1
The data memory is implemented as static RAM. Each register in the data memory has a 12-bit address, allowing up to 4096 bytes of data memory. Figure 4-6 and Figure 4-7 show the data memory organization for the PIC18CXX2 devices. The data memory map is divided into as many as 16 banks that contain 256 bytes each. The lower 4 bits of the Bank Select Register (BSR<3:0>) select which bank will be accessed. The upper 4 bits for the BSR are not implemented. The data memory contains Special Function Registers (SFR) and General Purpose Registers (GPR). The SFRs are used for control and status of the controller and peripheral functions, while GPRs are used for data storage and scratch pad operations in the user's application. The SFRs start at the last location of Bank 15 (0xFFF) and extend downwards. Any remaining space beyond the SFRs in the Bank may be implemented as GPRs. GPRs start at the first location of Bank 0 and grow upwards. Any read of an unimplemented location will read as '0's. The entire data memory may be accessed directly, or indirectly. Direct addressing may require the use of the BSR register. Indirect addressing requires the use of a File Select Register (FSRn) and corresponding Indirect File Operand (INDFn). Each FSR holds a 12-bit address value that can be used to access any location in the Data Memory map without banking. The instruction set and architecture allow operations across all banks. This may be accomplished by indirect addressing or by the use of the MOVFF instruction. The MOVFF instruction is a two-word/two-cycle instruction that moves a value from one register to another. To ensure that commonly used registers (SFRs and select GPRs) can be accessed in a single cycle, regardless of the current BSR values, an Access Bank is implemented. A segment of Bank 0 and a segment of Bank 15 comprise the Access RAM. Section 4.10 provides a detailed description of the Access RAM.
GENERAL PURPOSE REGISTER FILE
The register file can be accessed either directly, or indirectly. Indirect addressing operates using the File Select Registers (FSRn) and corresponding Indirect File Operand (INDFn). The operation of indirect addressing is shown in Section 4.12. Enhanced MCU devices may have banked memory in the GPR area. GPRs are not initialized by a Power-on Reset and are unchanged on all other RESETS. Data RAM is available for use as GPR registers by all instructions. The top half of bank 15 (0xF80 to 0xFFF) contains SFRs. All other banks of data memory contain GPR registers, starting with bank 0.
4.9.2
SPECIAL FUNCTION REGISTERS
The Special Function Registers (SFRs) are registers used by the CPU and Peripheral Modules for controlling the desired operation of the device. These registers are implemented as static RAM. A list of these registers is given in Table 4-1 and Table 4-2. The SFRs can be classified into two sets; those associated with the "core" function and those related to the peripheral functions. Those registers related to the "core" are described in this section, while those related to the operation of the peripheral features are described in the section of that peripheral feature. The SFRs are typically distributed among the peripherals whose functions they control. The unused SFR locations will be unimplemented and read as '0's. See Table 4-1 for addresses for the SFRs.
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PIC18CXX2
FIGURE 4-6:
BSR<3:0> = 0000b 00h Bank 0 FFh 00h Bank 1 FFh
DATA MEMORY MAP FOR PIC18C242/442
Data Memory Map Access RAM GPR GPR 1FFh 200h 000h 07Fh 080h 0FFh 100h
= 0001b
Access Bank 00h 7Fh 80h Access RAM high FFh (SFR's) Access RAM low
= 0010b = 1110b
Bank 2 to Bank 14
Unused Read '00h'
= 1111b
00h Bank 15 FFh
Unused SFR
EFFh F00h F7Fh F80h FFFh
When a = 0, the BSR is ignored and the Access Bank is used. The first 128 bytes are General Purpose RAM (from Bank 0). The second 128 bytes are Special Function Registers (from Bank 15).
When a = 1, the BSR is used to specify the RAM location that the instruction uses.
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PIC18CXX2
FIGURE 4-7:
BSR<3:0> = 0000b 00h Bank 0 FFh 00h Bank 1 FFh 00h Bank 2 = 0011b FFh 00h Bank 3 FFh = 0100b Bank 4 00h Bank 5 FFh GPR 5FFh 600h GPR 4FFh 500h GPR 3FFh 400h Access Bank 00h 7Fh 80h Access RAM high FFh (SFR's) Access RAM low
DATA MEMORY MAP FOR PIC18C252/452
Data Memory Map Access RAM GPR GPR 1FFh 200h GPR 2FFh 300h 000h 07Fh 080h 0FFh 100h
= 0001b
= 0010b
= 0101b
= 0110b = 1110b
Bank 6 to Bank 14
Unused Read '00h'
= 1111b
00h Bank 15 FFh
Unused SFR
EFFh F00h F7Fh F80h FFFh
When a = 0, the BSR is ignored and the Access Bank is used. The first 128 bytes are General Purpose RAM (from Bank 0). The second 128 bytes are Special Function Registers (from Bank 15).
When a = 1, the BSR is used to specify the RAM location that the instruction uses.
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PIC18CXX2
TABLE 4-1:
FFFh FFEh FFDh FFCh FFBh FFAh FF9h FF8h FF7h FF6h FF5h FF4h FF3h FF2h FF1h FF0h FEFh FEEh FEDh FECh FEBh FEAh FE9h FE8h FE7h FE6h FE5h FE4h FE3h FE2h FE1h FE0h
SPECIAL FUNCTION REGISTER MAP
TOSU TOSH TOSL STKPTR PCLATU PCLATH PCL TBLPTRU TBLPTRH TBLPTRL TABLAT PRODH PRODL INTCON INTCON2 INTCON3 INDF0
(3)
FDFh FDEh FDDh FDCh FDBh FDAh FD9h FD8h FD7h FD6h FD5h FD4h FD3h FD2h FD1h FD0h FCFh FCEh FCDh FCCh FCBh FCAh FC9h FC8h FC7h FC6h FC5h FC4h FC3h FC2h FC1h FC0h
INDF2(3) POSTINC2(3) POSTDEC2(3) PREINC2(3) PLUSW2 FSR2L STATUS TMR0H TMR0L T0CON -- OSCCON LVDCON WDTCON RCON TMR1H TMR1L T1CON TMR2 PR2 T2CON SSPBUF SSPADD SSPSTAT SSPCON1 SSPCON2 ADRESH ADRESL ADCON0 ADCON1 --
(3)
FBFh FBEh FBDh FBCh FBBh FBAh FB9h FB8h FB7h FB6h FB5h FB4h FB3h FB2h FB1h FB0h FAFh FAEh FADh FACh FABh FAAh FA9h FA8h FA7h FA6h FA5h FA4h FA3h FA2h FA1h FA0h
CCPR1H CCPR1L CCP1CON CCPR2H CCPR2L CCP2CON -- -- -- -- -- -- TMR3H TMR3L T3CON -- SPBRG RCREG TXREG TXSTA RCSTA -- -- -- -- -- -- -- -- IPR2 PIR2 PIE2
F9Fh F9Eh F9Dh F9Ch F9Bh F9Ah F99h F98h F97h F96h F95h F94h F93h F92h F91h F90h F8Fh F8Eh F8Dh F8Ch F8Bh F8Ah F89h F88h F87h F86h F85h F84h F83h F82h F81h F80h
IPR1 PIR1 PIE1 -- -- -- -- -- -- TRISE(2) TRISD(2) TRISC TRISB TRISA -- -- -- -- LATE(2) LATD(2) LATC LATB LATA -- -- -- -- PORTE(2) PORTD(2) PORTC PORTB PORTA
FSR2H
POSTINC0(3) POSTDEC0(3) PREINC0 FSR0H FSR0L WREG INDF1(3) POSTINC1(3) POSTDEC1(3) PREINC1(3) PLUSW1(3) FSR1H FSR1L BSR
(3)
PLUSW0(3)
Note 1: Unimplemented registers are read as '0'. 2: This register is not available on PIC18C2X2 devices. 3: This is not a physical register.
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PIC18CXX2
TABLE 4-2:
File Name TOSU TOSH TOSL STKPTR PCLATU PCLATH PCL TBLPTRU TBLPTRH TBLPTRL TABLAT PRODH PRODL INTCON INTCON2 INTCON3 INDF0 POSTINC0 POSTDEC0 PREINC0 PLUSW0 FSR0H FSR0L WREG INDF1 POSTINC1 POSTDEC1 PREINC1 PLUSW1 FSR1H FSR1L BSR INDF2 POSTINC2 POSTDEC2 PREINC2 PLUSW2 FSR2H FSR2L STATUS TMR0H TMR0L T0CON OSCCON LVDCON Legend: Note 1: 2:
REGISTER FILE SUMMARY
Bit 7 -- Bit 6 -- Bit 5 -- Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on POR, BOR
---0 0000 0000 0000 0000 0000
Details on page: 37 37 37 38 39 39 39 57 57 57 57 61 61 65 66 67 50 50 50 50 50 50 50
Top-of-Stack Upper Byte (TOS<20:16>)
Top-of-Stack High Byte (TOS<15:8>) Top-of-Stack Low Byte (TOS<7:0>) STKFUL -- STKUNF -- -- -- Return Stack Pointer Holding Register for PC<20:16>
00-0 0000 ---0 0000 0000 0000 0000 0000
Holding Register for PC<15:8> PC Low Byte (PC<7:0>) -- -- bit21(2) Program Memory Table Pointer Upper Byte (TBLPTR<20:16>)
---0 0000 0000 0000 0000 0000 0000 0000 xxxx xxxx xxxx xxxx
Program Memory Table Pointer High Byte (TBLPTR<15:8>) Program Memory Table Pointer Low Byte (TBLPTR<7:0>) Program Memory Table Latch Product Register High Byte Product Register Low Byte GIE/GIEH RBPU INT2IP PEIE/GIEL INTEDG0 INT1IP TMR0IE INTEDG1 -- INT0IE INTEDG2 INT2IE RBIE -- INT1IE TMR0IF TMR0IP -- INT0IF -- INT2IF RBIF RBIP INT1IF
0000 000x 1111 -1-1 11-0 0-00
Uses contents of FSR0 to address data memory - value of FSR0 not changed (not a physical register) Uses contents of FSR0 to address data memory - value of FSR0 post-incremented (not a physical register) Uses contents of FSR0 to address data memory - value of FSR0 post-decremented (not a physical register) Uses contents of FSR0 to address data memory - value of FSR0 pre-incremented (not a physical register) Uses contents of FSR0 to address data memory - value of FSR0 pre-incremented (not a physical register) value of FSR0 offset by value in WREG -- -- -- -- Indirect Data Memory Address Pointer 0 High Byte
N/A N/A N/A N/A N/A
---- 0000 xxxx xxxx xxxx xxxx
Indirect Data Memory Address Pointer 0 Low Byte Working Register Uses contents of FSR1 to address data memory - value of FSR1 not changed (not a physical register) Uses contents of FSR1 to address data memory - value of FSR1 post-incremented (not a physical register) Uses contents of FSR1 to address data memory - value of FSR1 post-decremented (not a physical register) Uses contents of FSR1 to address data memory - value of FSR1 pre-incremented (not a physical register) Uses contents of FSR1 to address data memory - value of FSR1 pre-incremented (not a physical register) value of FSR1 offset by value in WREG -- -- -- -- Indirect Data Memory Address Pointer 1 High Byte
N/A N/A N/A N/A N/A
---- 0000 xxxx xxxx
50 50 50 50 50 50 50 49 50 50 50 50 50 50 50 52 95 95 93 20 175
Indirect Data Memory Address Pointer 1 Low Byte -- -- -- -- Bank Select Register
---- 0000
Uses contents of FSR2 to address data memory - value of FSR2 not changed (not a physical register) Uses contents of FSR2 to address data memory - value of FSR2 post-incremented (not a physical register) Uses contents of FSR2 to address data memory - value of FSR2 post-decremented (not a physical register) Uses contents of FSR2 to address data memory - value of FSR2 pre-incremented (not a physical register) Uses contents of FSR2 to address data memory - value of FSR2 pre-incremented (not a physical register) value of FSR2 offset by value in WREG -- -- -- -- Indirect Data Memory Address Pointer 2 High Byte
N/A N/A N/A N/A N/A
---- 0000 xxxx xxxx
Indirect Data Memory Address Pointer 2 Low Byte -- -- -- N OV Z DC C
---x xxxx 0000 0000 xxxx xxxx
Timer0 Register High Byte Timer0 Register Low Byte TMR0ON -- -- T08BIT -- -- T0CS -- IRVST T0SE -- LVDEN PSA -- LVDL3 T0PS2 -- LVDL2 T0PS1 -- LVDL1 T0PS0 SCS LVDL0
1111 1111 ---- ---0 --00 0101
x = unknown, u = unchanged, - = unimplemented, q = value depends on condition RA6 and associated bits are configured as port pins in RCIO and ECIO oscillator mode only, and read '0' in all other oscillator modes. Bit 21 of the TBLPTRU allows access to the device configuration bits.
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PIC18CXX2
TABLE 4-2:
File Name WDTCON RCON TMR1H TMR1L T1CON TMR2 PR2 T2CON SSPBUF SSPADD SSPSTAT SSPCON1 SSPCON2 ADRESH ADRESL ADCON0 ADCON1 CCPR1H CCPR1L CCP1CON CCPR2H CCPR2L CCP2CON TMR3H TMR3L T3CON SPBRG RCREG TXREG TXSTA RCSTA Legend: Note 1: 2:
REGISTER FILE SUMMARY (CONTINUED)
Bit 7 -- IPEN Bit 6 -- LWRT Bit 5 -- -- Bit 4 -- RI Bit 3 -- TO Bit 2 -- PD Bit 1 -- POR Bit 0 SWDTE BOR Value on POR, BOR
---- ---0 0q-1 11qq xxxx xxxx xxxx xxxx
Details on page: 183 53, 56, 74 97 97 97 101 102 101 121 128 116 118 120 171,172 171,172 165 166 111, 113 111, 113 107 111, 113 111, 113 107 103 103 103 151 158, 161, 163 156, 159, 162 149 150
Timer1 Register High Byte Timer1 Register Low Byte RD16 Timer2 Register Timer2 Period Register -- TOUTPS3 TOUTPS2 TOUTPS1 TOUTPS0 TMR2ON T2CKPS1 T2CKPS0 -- T1CKPS1 T1CKPS0 T1OSCEN T1SYNC TMR1CS TMR1ON
0-00 0000 0000 0000 1111 1111 -000 0000 xxxx xxxx 0000 0000
SSP Receive Buffer/Transmit Register SSP Address Register in I2C Slave Mode. SSP Baud Rate Reload Register in I2C Master Mode. SMP WCOL GCEN CKE SSPOV ACKSTAT D/A SSPEN ACKDT P CKP ACKEN S SSPM3 RCEN R/W SSPM2 PEN UA SSPM1 RSEN BF SSPM0 SEN
0000 0000 0000 0000 0000 0000 xxxx xxxx xxxx xxxx
A/D Result Register High Byte A/D Result Register Low Byte ADCS1 ADFM ADCS0 ADCS2 CHS2 -- CHS1 -- CHS0 PCFG3 GO/DONE PCFG2 -- PCFG1 ADON PCFG0
0000 00-0 00-- 0000 xxxx xxxx xxxx xxxx
Capture/Compare/PWM Register1 High Byte Capture/Compare/PWM Register1 Low Byte -- -- DC1B1 DC1B0 CCP1M3 CCP1M2 CCP1M1 CCP1M0
--00 0000 xxxx xxxx xxxx xxxx
Capture/Compare/PWM Register2 High Byte Capture/Compare/PWM Register2 Low Byte -- -- DC2B1 DC2B0 CCP2M3 CCP2M2 CCP2M1 CCP2M0
--00 0000 xxxx xxxx xxxx xxxx
Timer3 Register High Byte Timer3 Register Low Byte RD16 T3CCP2 T3CKPS1 T3CKPS0 T3CCP1 T3SYNC TMR3CS TMR3ON
0000 0000 0000 0000 0000 0000 0000 0000
USART1 Baud Rate Generator USART1 Receive Register USART1 Transmit Register CSRC SPEN TX9 RX9 TXEN SREN SYNC CREN -- ADDEN BRGH FERR TRMT OERR TX9D RX9D
0000 -010 0000 000x
x = unknown, u = unchanged, - = unimplemented, q = value depends on condition RA6 and associated bits are configured as port pins in RCIO and ECIO oscillator mode only, and read '0' in all other oscillator modes. Bit 21 of the TBLPTRU allows access to the device configuration bits.
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PIC18CXX2
TABLE 4-2:
File Name IPR2 PIR2 PIE2 IPR1 PIR1 PIE1 TRISE TRISD TRISC TRISB TRISA LATE LATD LATC LATB LATA PORTE PORTD PORTC PORTB PORTA Legend: Note 1: 2:
REGISTER FILE SUMMARY (CONTINUED)
Bit 7 -- -- -- PSPIP PSPIF PSPIE IBF Bit 6 -- -- -- ADIP ADIF ADIE OBF Bit 5 -- -- -- RCIP RCIF RCIE IBOV Bit 4 -- -- -- TXIP TXIF TXIE PSPMODE Bit 3 BCLIP BCLIF BCLIE SSPIP SSPIF SSPIE -- Bit 2 LVDIP LVDIF LVDIE CCP1IP CCP1IF CCP1IE Bit 1 TMR3IP TMR3IF TMR3IE TMR2IP TMR2IF TMR2IE Bit 0 CCP2IP CCP2IF CCP2IE TMR1IP TMR1IF TMR1IE Value on POR, BOR
---- 1111 ---- 0000 ---- 0000 1111 1111 0000 0000 0000 0000 0000 -111 1111 1111 1111 1111 1111 1111 -111 1111
Details on page: 73 69 71 72 68 70 88 85 83 80 77 87 85 83 80 77 87 85 83 80 77
Data Direction bits for PORTE
Data Direction Control Register for PORTD Data Direction Control Register for PORTC Data Direction Control Register for PORTB -- -- TRISA6(1) -- Data Direction Control Register for PORTA -- -- -- Read PORTE Data Latch, Write PORTE Data Latch
---- -xxx xxxx xxxx xxxx xxxx xxxx xxxx -xxx xxxx ---- -000 xxxx xxxx xxxx xxxx xxxx xxxx -x0x 0000
Read PORTD Data Latch, Write PORTD Data Latch Read PORTC Data Latch, Write PORTC Data Latch Read PORTB Data Latch, Write PORTB Data Latch -- LATA6(1) Read PORTA Data Latch, Write PORTA Data Latch(1)
Read PORTE pins, Write PORTE Data Latch Read PORTD pins, Write PORTD Data Latch Read PORTC pins, Write PORTC Data Latch Read PORTB pins, Write PORTB Data Latch -- RA6(1) Read PORTA pins, Write PORTA Data Latch(1)
x = unknown, u = unchanged, - = unimplemented, q = value depends on condition RA6 and associated bits are configured as port pins in RCIO and ECIO oscillator mode only, and read '0' in all other oscillator modes. Bit 21 of the TBLPTRU allows access to the device configuration bits.
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PIC18CXX2
4.10 Access Bank
The Access Bank is an architectural enhancement, which is very useful for C compiler code optimization. The techniques used by the C compiler may also be useful for programs written in assembly. This data memory region can be used for: * * * * * Intermediate computational values Local variables of subroutines Faster context saving/switching of variables Common variables Faster evaluation/control of SFRs (no banking) can be accessed without any software overhead. This is useful for testing status flags and modifying control bits.
4.11
Bank Select Register (BSR)
The need for a large general purpose memory space dictates a RAM banking scheme. The data memory is partitioned into sixteen banks. When using direct addressing, the BSR should be configured for the desired bank. BSR<3:0> holds the upper 4 bits of the 12-bit RAM address. The BSR<7:4> bits will always read '0's, and writes will have no effect. A MOVLB instruction has been provided in the instruction set to assist in selecting banks. If the currently selected bank is not implemented, any read will return all '0's and all writes are ignored. The STATUS register bits will be set/cleared as appropriate for the instruction performed. Each Bank extends up to FFh (256 bytes). All data memory is implemented as static RAM. A MOVFF instruction ignores the BSR, since the 12-bit addresses are embedded into the instruction word. Section 4.12 provides a description of indirect addressing, which allows linear addressing of the entire RAM space.
The Access Bank is comprised of the upper 128 bytes in Bank 15 (SFRs) and the lower 128 bytes in Bank 0. These two sections will be referred to as Access RAM High and Access RAM Low, respectively. Figure 4-6 and Figure 4-7 indicate the Access RAM areas. A bit in the instruction word specifies if the operation is to occur in the bank specified by the BSR register or in the Access Bank. This bit is denoted by the 'a' bit (for access bit). When forced in the Access Bank (a = '0'), the last address in Access RAM Low is followed by the first address in Access RAM High. Access RAM High maps the Special Function registers, so that these registers
FIGURE 4-8:
DIRECT ADDRESSING
Direct Addressing
BSR<3:0> 7 From Opcode(3) 0
Bank Select(2)
Location Select(3) 00h 000h 01h 100h 0Eh E00h 0Fh F00h
Data Memory(1)
0FFh
1FFh
EFFh
FFFh
Bank 0
Note 1: For register file map detail, see Table 4-1.
Bank 1
Bank 14
Bank 15
2: The access bit of the instruction can be used to force an override of the selected bank (BSR<3:0>) to the registers of the Access Bank. 3: The MOVFF instruction embeds the entire 12-bit address in the instruction.
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PIC18CXX2
4.12 Indirect Addressing, INDF and FSR Registers
If INDF0, INDF1 or INDF2 are read indirectly via an FSR, all '0's are read (zero bit is set). Similarly, if INDF0, INDF1 or INDF2 are written to indirectly, the operation will be equivalent to a NOP instruction and the STATUS bits are not affected.
Indirect addressing is a mode of addressing data memory, where the data memory address in the instruction is not fixed. An FSR register is used as a pointer to the data memory location that is to be read or written. Since this pointer is in RAM, the contents can be modified by the program. This can be useful for data tables in the data memory and for software stacks. Figure 4-9 shows the operation of indirect addressing. This shows the moving of the value to the data memory address, specified by the value of the FSR register. Indirect addressing is possible by using one of the INDF registers. Any instruction using the INDF register actually accesses the register pointed to by the File Select Register, FSR. Reading the INDF register itself, indirectly (FSR = '0'), will read 00h. Writing to the INDF register indirectly, results in a no operation. The FSR register contains a 12-bit address, which is shown in Figure 4-10. The INDFn register is not a physical register. Addressing INDFn actually addresses the register whose address is contained in the FSRn register (FSRn is a pointer). This is indirect addressing. Example 4-4 shows a simple use of indirect addressing to clear the RAM in Bank1 (locations 100h-1FFh) in a minimum number of instructions.
4.12.1
INDIRECT ADDRESSING OPERATION
Each FSR register has an INDF register associated with it, plus four additional register addresses. Performing an operation on one of these five registers determines how the FSR will be modified during indirect addressing. When data access is done to one of the five INDFn locations, the address selected will configure the FSRn register to: * Do nothing to FSRn after an indirect access (no change) - INDFn * Auto-decrement FSRn after an indirect access (post-decrement) - POSTDECn * Auto-increment FSRn after an indirect access (post-increment) - POSTINCn * Auto-increment FSRn before an indirect access (pre-increment) - PREINCn * Use the value in the WREG register as an offset to FSRn. Do not modify the value of the WREG or the FSRn register after an indirect access (no change) - PLUSWn When using the auto-increment or auto-decrement features, the effect on the FSR is not reflected in the STATUS register. For example, if the indirect address causes the FSR to equal '0', the Z bit will not be set. Incrementing or decrementing an FSR affects all 12 bits. That is, when FSRnL overflows from an increment, FSRnH will be incremented automatically. Adding these features allows the FSRn to be used as a stack pointer, in addition to its uses for table operations in data memory. Each FSR has an address associated with it that performs an indexed indirect access. When a data access to this INDFn location (PLUSWn) occurs, the FSRn is configured to add the signed value in the WREG register and the value in FSR to form the address before an indirect access. The FSR value is not changed. If an FSR register contains a value that points to one of the INDFn, an indirect read will read 00h (zero bit is set), while an indirect write will be equivalent to a NOP (STATUS bits are not affected).
EXAMPLE 4-4:
HOW TO CLEAR RAM (BANK1) USING INDIRECT ADDRESSING
; ; ; ; ; ; Clear INDF register & inc pointer All done w/ Bank1? NO, clear next YES, continue
NEXT
LFSR CLRF
FSR0, 0x100 POSTINC0
BTFSS FSR0H, 1 GOTO NEXT CONTINUE
There are three indirect addressing registers. To address the entire data memory space (4096 bytes), these registers are 12-bit wide. To store the 12-bits of addressing information, two 8-bit registers are required. These indirect addressing registers are: 1. 2. 3. FSR0: composed of FSR0H:FSR0L FSR1: composed of FSR1H:FSR1L FSR2: composed of FSR2H:FSR2L
In addition, there are registers INDF0, INDF1 and INDF2, which are not physically implemented. Reading or writing to these registers activates indirect addressing, with the value in the corresponding FSR register being the address of the data. If an instruction writes a value to INDF0, the value will be written to the address pointed to by FSR0H:FSR0L. A read from INDF1 reads the data from the address pointed to by FSR1H:FSR1L. INDFn can be used in code anywhere an operand can be used.
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PIC18CXX2
If an indirect addressing operation is done where the target address is an FSRnH or FSRnL register, the write operation will dominate over the pre- or postincrement/decrement functions.
FIGURE 4-9:
INDIRECT ADDRESSING OPERATION
RAM 0h
Instruction Executed Opcode Address FFFh 12 File Address = access of an indirect addressing register
BSR<3:0> Instruction Fetched Opcode 4
12 8 File
12
FSR
FIGURE 4-10:
INDIRECT ADDRESSING
Indirect Addressing
11 FSR Register 0
Location Select
0000h
Data Memory(1)
0FFFh Note 1: For register file map detail, see Table 4-1.
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DS39026C-page 51
PIC18CXX2
4.13 STATUS Register
The STATUS register, shown in Register 4-2, contains the arithmetic status of the ALU. The STATUS register can be the destination for any instruction, as with any other register. If the STATUS register is the destination for an instruction that affects the Z, DC, C, OV or N bits, then the write to these five bits is disabled. These bits are set or cleared according to the device logic. Therefore, the result of an instruction with the STATUS register as destination may be different than intended. For example, CLRF STATUS will clear the upper three bits and set the Z bit. This leaves the STATUS register as 000u u1uu (where u = unchanged). It is recommended, therefore, that only BCF, BSF, SWAPF, MOVFF and MOVWF instructions are used to alter the STATUS register, because these instructions do not affect the Z, C, DC, OV or N bits from the STATUS register. For other instructions not affecting any status bits, see Table 19-2. Note: The C and DC bits operate as a borrow and digit borrow bit respectively, in subtraction.
REGISTER 4-2:
STATUS REGISTER
U-0 -- bit 7 U-0 -- U-0 -- R/W-x N R/W-x OV R/W-x Z R/W-x DC R/W-x C bit 0
bit 7-5 bit 4
Unimplemented: Read as '0' N: Negative bit This bit is used for signed arithmetic (2's complement). It indicates whether the result was negative, (ALU MSB = 1). 1 = Result was negative 0 = Result was positive OV: Overflow bit This bit is used for signed arithmetic (2's complement). It indicates an overflow of the 7-bit magnitude, which causes the sign bit (bit7) to change state. 1 = Overflow occurred for signed arithmetic (in this arithmetic operation) 0 = No overflow occurred Z: Zero bit 1 = The result of an arithmetic or logic operation is zero 0 = The result of an arithmetic or logic operation is not zero DC: Digit carry/borrow bit For ADDWF, ADDLW, SUBLW, and SUBWF instructions 1 = A carry-out from the 4th low order bit of the result occurred 0 = No carry-out from the 4th low order bit of the result Note: For borrow, the polarity is reversed. A subtraction is executed by adding the two's complement of the second operand. For rotate (RRF, RLF) instructions, this bit is loaded with either the bit 4 or bit 3 of the source register.
bit 3
bit 2
bit 1
bit 0
C: Carry/borrow bit For ADDWF, ADDLW, SUBLW, and SUBWF instructions 1 = A carry-out from the Most Significant bit of the result occurred 0 = No carry-out from the Most Significant bit of the result occurred Note: For borrow, the polarity is reversed. A subtraction is executed by adding the two's complement of the second operand. For rotate (RRF, RLF) instructions, this bit is loaded with either the high or low order bit of the source register.
Legend: R = Readable bit - n = Value at POR reset W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown
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4.13.1 RCON REGISTER
. Note 1: If the BOREN configuration bit is set (Brown-out Reset enabled), the BOR bit is '1' on a Power-on Reset. After a Brownout Reset has occurred, the BOR bit will be clear and must be set by firmware to indicate the occurrence of the next Brownout Reset. If the BOREN configuration bit is clear (Brown-out Reset disabled), BOR is unknown after Power-on Reset and Brown-out Reset conditions. 2: It is recommended that the POR bit be set after a Power-on Reset has been detected, so that subsequent Power-on Resets may be detected. The Reset Control (RCON) register contains flag bits that allow differentiation between the sources of a device RESET. These flags include the TO, PD, POR, BOR and RI bits. This register is readable and writable.
REGISTER 4-3:
RCON REGISTER
R/W-0 IPEN bit 7 R/W-0 LWRT U-0 -- R/W-1 RI R/W-1 TO R/W-1 PD R/W-0 POR R/W-0 BOR bit 0
bit 7
IPEN: Interrupt Priority Enable bit 1 = Enable priority levels on interrupts 0 = Disable priority levels on interrupts (16CXXX compatibility mode) LWRT: Long Write Enable bit 1 = Enable TBLWT to internal program memory Once this bit is set, it can only be cleared by a POR or MCLR Reset. 0 = Disable TBLWT to internal program memory; TBLWT only to external program memory Unimplemented: Read as '0' RI: RESET Instruction Flag bit 1 = The RESET instruction was not executed 0 = The RESET instruction was executed causing a device RESET (must be set in software after a Brown-out Reset occurs) TO: Watchdog Time-out Flag bit 1 = After power-up, CLRWDT instruction, or SLEEP instruction 0 = A WDT time-out occurred PD: Power-down Detection Flag bit 1 = After power-up or by the CLRWDT instruction 0 = By execution of the SLEEP instruction POR: Power-on Reset Status bit 1 = A Power-on Reset has not occurred 0 = A Power-on Reset occurred (must be set in software after a Power-on Reset occurs) BOR: Brown-out Reset Status bit 1 = A Brown-out Reset has not occurred 0 = A Brown-out Reset occurred (must be set in software after a Brown-out Reset occurs) Legend: R = Readable bit - n = Value at POR reset W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown
bit 6
bit 5 bit 4
bit 3
bit 2
bit 1
bit 0
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NOTES:
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5.0 TABLE READS/TABLE WRITES
Enhanced devices have two memory spaces: the program memory space and the data memory space. The program memory space is 16-bits wide, while the data memory space is 8 bits wide. Table Reads and Table Writes have been provided to move data between these two memory spaces through an 8-bit register (TABLAT). The operations that allow the processor to move data between the data and program memory spaces are: * Table Read (TBLRD) * Table Write (TBLWT) Table Read operations retrieve data from program memory and place it into the data memory space. Figure 5-1 shows the operation of a Table Read with program and data memory. Table Write operations store data from the data memory space into program memory. Figure 5-2 shows the operation of a Table Write with program and data memory. Table operations work with byte entities. A table block containing data is not required to be word aligned, so a table block can start and end at any byte address. If a Table Write is being used to write an executable program to program memory, program instructions will need to be word aligned.
FIGURE 5-1:
TABLE READ OPERATION
Instruction: TBLRD*
Table Pointer(1) TBLPTRU TBLPTRH TBLPTRL
Program Memory Table Latch (8-bit) TABLAT
Program Memory (TBLPTR)
Note 1: Table Pointer points to a byte in program memory.
FIGURE 5-2:
TABLE WRITE OPERATION
Instruction: TBLWT*
Program Memory Table Pointer TBLPTRU
(1)
Table Latch (8-bit) TBLPTRL TABLAT
TBLPTRH
Program Memory (TBLPTR)
Note 1: Table Pointer points to a byte in program memory.
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5.1 Control Registers
5.1.1 RCON REGISTER
Several control registers are used in conjunction with the TBLRD and TBLWT instructions. These include the: * TBLPTR registers * TABLAT register * RCON register The LWRT bit specifies the operation of Table Writes to internal memory when the VPP voltage is applied to the MCLR pin. When the LWRT bit is set, the controller continues to execute user code, but long Table Writes are allowed (for programming internal program memory) from user mode. The LWRT bit can be cleared only by performing either a POR or MCLR Reset.
REGISTER 5-1:
RCON REGISTER (ADDRESS: FD0h)
R/W-0 IPEN bit 7 R/W-0 LWRT U-0 -- R/W-1 RI R/W-1 TO R/W-1 PD R/W-0 POR R/W-0 BOR bit 0
bit 7
IPEN: Interrupt Priority Enable bit 1 = Enable priority levels on interrupts 0 = Disable priority levels on interrupts (16CXXX compatibility mode) LWRT: Long Write Enable bit 1 = Enable TBLWT to internal program memory 0 = Disable TBLWT to internal program memory. Note: Only cleared on a POR or MCLR Reset. This bit has no effect on TBLWTs to external program memory.
bit 6
bit 5 bit 4
Unimplemented: Read as '0' RI: RESET Instruction Flag bit 1 = No RESET instruction occurred 0 = A RESET instruction occurred TO: Time-out bit 1 = After power-up, CLRWDT instruction, or SLEEP instruction 0 = A WDT time-out occurred PD: Power-down bit 1 = After power-up or by the CLRWDT instruction 0 = By execution of the SLEEP instruction POR: Power-on Reset Status bit 1 = No Power-on Reset occurred 0 = A Power-on Reset occurred (must be set in software after a Power-on Reset occurs) BOR: Brown-out Reset Status bit 1 = No Brown-out Reset or POR Reset occurred 0 = A Brown-out Reset or POR Reset occurred (must be set in software after a Brown-out Reset occurs) Legend: R = Readable bit - n = Value at POR reset W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown
bit 3
bit 2
bit 1
bit 0
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PIC18CXX2
5.1.2 TABLAT - TABLE LATCH REGISTER 5.1.3
The Table Latch (TABLAT) is an 8-bit register mapped into the SFR space. The Table Latch is used to hold 8-bit data during data transfers between program memory and data memory.
TBLPTR - TABLE POINTER REGISTER
The Table Pointer (TBLPTR) addresses a byte within the program memory. The TBLPTR is comprised of three SFR registers (Table Pointer Upper Byte, High Byte and Low Byte). These three registers (TBLPTRU:TBLPTRH:TBLPTRL) join to form a 22-bit wide pointer. The lower 21-bits allow the device to address up to 2 Mbytes of program memory space. The 22nd bit allows access to the Device ID, the User ID and the Configuration bits. The Table Pointer, TBLPTR, is used by the TBLRD and TBLWT instructions. These instructions can update the TBLPTR in one of four ways, based on the table operation. These operations are shown in Table 5-1. These operations on the TBLPTR only affect the lower 21-bits.
TABLE 5-1:
Example TBLRD* TBLWT* TBLRD*+ TBLWT*+ TBLRD*TBLWT*TBLRD+* TBLWT+*
TABLE POINTER OPERATIONS WITH TBLRD AND TBLWT INSTRUCTIONS
Operation on Table Pointer TBLPTR is not modified TBLPTR is incremented after the read/write TBLPTR is decremented after the read/write TBLPTR is incremented before the read/write
5.2
5.2.1
Internal Program Memory Read/ Writes
TABLE READ OVERVIEW (TBLRD)
The TBLRD instructions are used to read data from program memory to data memory. TBLPTR points to a byte address in program space. Executing TBLRD places the byte pointed to into TABLAT. In addition, TBLPTR can be modified automatically for the next Table Read operation. Table Reads from program memory are performed one byte at a time. The instruction will load TABLAT with the one byte from program memory pointed to by TBLPTR.
When a Table Write occurs to an even program memory address (TBLPTR<0> = 0), the contents of TABLAT are transferred to an internal holding register. This is performed as a short write and the program memory block is not actually programmed at this time. The holding register is not accessible by the user. When a Table Write occurs to an odd program memory address (TBLPTR<0>=1), a long write is started. During the long write, the contents of TABLAT are written to the high byte of the program memory block and the contents of the holding register are transferred to the low byte of the program memory block. Figure 5-3 shows the holding register and the program memory write blocks. If a single byte is to be programmed, the low (even) byte of the destination program word should be read using TBLRD*, modified or changed, if required, and written back to the same address using TBLWT*+. The high (odd) byte should be read using TBLRD*, modified or changed if required, and written back to the same address using TBLWT. A write to the odd address will cause a long write to begin. This process ensures that existing data in either byte will not be changed unless desired.
5.2.2
INTERNAL PROGRAM MEMORY WRITE BLOCK SIZE
The internal program memory of PIC18CXXX devices is written in blocks. For PIC18CXX2 devices, the write block size is 2 bytes. Consequently, Table Write operations to internal program memory are performed in pairs, one byte at a time.
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FIGURE 5-3: HOLDING REGISTER AND THE WRITE BLOCK
Program Memory (x 2-bits) Block n Write Block MSB Block n + 1 Holding Register
Block n + 2 The write to the MSB of the Write Block causes the entire block to be written to program memory. The program memory block that is written depends on the address that is written to in the MSB of the Write Block.
5.2.2.1
Operation
5.2.2.2
Sequence of Events
The long write is what actually programs words of data into the internal memory. When a TBLWT to the MSB of the write block occurs, instruction execution is halted. During this time, programming voltage and the data stored in internal latches is applied to program memory. For a long write to occur: 1. 2. 3. MCLR/VPP pin must be at the programming voltage LWRT bit must be set TBLWT to the address of the MSB of the write block
The sequence of events for programming an internal program memory location should be: Enable the interrupt that terminates the long write. Disable all other interrupts. 2. Clear the source interrupt flag. 3. If Interrupt Service Routine execution is desired when the device wakes, enable global interrupts. 4. Set LWRT bit in the RCON register. 5. Raise MCLR/VPP pin to the programming voltage, VPP. 6. Clear the WDT (if enabled). 7. Set the interrupt source to interrupt at the required time. 8. Execute the Table Write for the lower (even) byte. This will be a short write. 9. Execute the Table Write for the upper (odd) byte. This will be a long write. The microcontroller will then halt internal operations. (This is not the same as SLEEP mode, as the clocks and peripherals will continue to run.) The interrupt will cause the microcontroller to resume operation. 10. If GIE was set, service the interrupt request. 11. Lower MCLR/VPP pin to VDD. 12. Verify the memory location (Table Read). 1.
If the LWRT bit is clear, a short write will occur and program memory will not be changed. If the TBLWT is not to the MSB of the write block, then the programming phase is not initiated. Setting the LWRT bit enables long writes when the MCLR pin is taken to VPP voltage. Once the LWRT bit is set, it can be cleared only by performing a POR or MCLR Reset. To ensure that the memory location has been well programmed, a minimum programming time is required. The long write can be terminated after the programming time has expired by a RESET or an interrupt. Having only one interrupt source enabled to terminate the long write ensures that no unintended interrupts will prematurely terminate the long write.
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5.2.3 INTERRUPTS
The long write must be terminated by a RESET or any interrupt. The interrupt source must have its interrupt enable bit set. When the source sets its interrupt flag, programming will terminate. This will occur, regardless of the settings of interrupt priority bits, the GIE/GIEH bit, or the PIE/GIEL bit. Depending on the states of interrupt priority bits, the GIE/GIEH bit or the PIE/GIEL bit, program execution can either be vectored to the high or low priority Interrupt Service Routine (ISR), or continue execution from where programming commenced. In either case, the interrupt flag will not be cleared when programming is terminated and will need to be cleared by the software.
TABLE 5-2:
GIE/ GIEH X X 0 (default) 0 (default) 1 0 (default) 1
LONG WRITE EXECUTION, INTERRUPT ENABLE BITS AND INTERRUPT RESULTS
PIE/ GIEL X X Priority X X X 1 high priority (default) 0 low 0 low 1 high priority (default) Interrupt Enable 0 (default) 1 1 1 1 1 Interrupt Flag X 0 1 1 1 1 Action Long write continues even if interrupt flag becomes set. Long write continues, will resume operations when the interrupt flag is set. Terminates long write, executes next instruction. Interrupt flag not cleared. Terminates long write, executes next instruction. Interrupt flag not cleared. Terminates long write, executes next instruction. Interrupt flag not cleared. Terminates long write, branches to low priority interrupt vector. Interrupt flag can be cleared by ISR. Terminates long write, branches to high priority interrupt vector. Interrupt flag can be cleared by ISR.
0 (default) 1 0 (default) 1 0 (default)
1
1
5.2.4
UNEXPECTED TERMINATION OF WRITE OPERATIONS
If a write is terminated by an unplanned event such as loss of power, an unexpected RESET, or an interrupt that was not disabled, the memory location just programmed should be verified and reprogrammed if needed.
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PIC18CXX2
6.0
6.1
8 X 8 HARDWARE MULTIPLIER
Introduction
Making the 8 x 8 multiplier execute in a single cycle gives the following advantages: * Higher computational throughput * Reduces code size requirements for multiply algorithms The performance increase allows the device to be used in applications previously reserved for Digital Signal Processors. Table 6-1 shows a performance comparison between enhanced devices using the single cycle hardware multiply, and performing the same function without the hardware multiply.
An 8 x 8 hardware multiplier is included in the ALU of the PIC18CXX2 devices. By making the multiply a hardware operation, it completes in a single instruction cycle. This is an unsigned multiply that gives a 16-bit result. The result is stored into the 16-bit product register pair (PRODH:PRODL). The multiplier does not affect any flags in the ALUSTA register.
TABLE 6-1:
Routine
PERFORMANCE COMPARISON
Multiply Method Without hardware multiply Hardware multiply Without hardware multiply Hardware multiply Without hardware multiply Hardware multiply Without hardware multiply Hardware multiply Program Memory (Words) 13 1 33 6 21 24 52 36 Cycles (Max) 69 1 91 6 242 24 254 36 Time @ 40 MHz 6.9 s 100 ns 9.1 s 600 ns 24.2 s 2.4 s 25.4 s 3.6 s @ 10 MHz 27.6 s 400 ns 36.4 s 2.4 s 96.8 s 9.6 s 102.6 s 14.4 s @ 4 MHz 69 s 1 s 91 s 6 s 242 s 24 s 254 s 36 s
8 x 8 unsigned 8 x 8 signed 16 x 16 unsigned 16 x 16 signed
6.2
Operation
EXAMPLE 6-2:
MOVF MULWF BTFSC SUBWF MOVF BTFSC SUBWF ARG1, ARG2 W
Example 6-1 shows the sequence to do an 8 x 8 unsigned multiply. Only one instruction is required when one argument of the multiply is already loaded in the WREG register. Example 6-2 shows the sequence to do an 8 x 8 signed multiply. To account for the sign bits of the arguments, each argument's Most Significant bit (MSb) is tested and the appropriate subtractions are done.
8 x 8 SIGNED MULTIPLY ROUTINE
; ; ; ; ; ARG1 * ARG2 -> PRODH:PRODL Test Sign Bit PRODH = PRODH - ARG1
ARG2, SB PRODH, F ARG2, W ARG1, SB PRODH, F
EXAMPLE 6-1:
MOVF MULWF ARG1, W ARG2
8 x 8 UNSIGNED MULTIPLY ROUTINE
; ; ARG1 * ARG2 -> ; PRODH:PRODL
; Test Sign Bit ; PRODH = PRODH ; - ARG2
Example 6-3 shows the sequence to do a 16 x 16 unsigned multiply. Equation 6-1 shows the algorithm that is used. The 32-bit result is stored in four registers, RES3:RES0.
EQUATION 6-1:
16 x 16 UNSIGNED MULTIPLICATION ALGORITHM
RES3:RES0
= =
ARG1H:ARG1L * ARG2H:ARG2L (ARG1H * ARG2H * 216)+ (ARG1H * ARG2L * 28)+ (ARG1L * ARG2H * 28)+ (ARG1L * ARG2L)
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EXAMPLE 6-3:
MOVF MULWF MOVFF MOVFF ; MOVF MULWF MOVFF MOVFF ; MOVF MULWF MOVF ADDWF MOVF ADDWFC CLRF ADDWFC ; MOVF MULWF MOVF ADDWF MOVF ADDWFC CLRF ADDWFC ARG1H, W ARG2L PRODL, RES1, PRODH, RES2, WREG, RES3, W F W F F F ; ; ; ; ; ; ; ; ; ARG1H * ARG2L -> PRODH:PRODL Add cross products ARG1L, W ARG2H PRODL, RES1, PRODH, RES2, WREG, RES3, W F W F F F ; ; ; ; ; ; ; ; ARG1L * ARG2H -> PRODH:PRODL Add cross products ARG1H, W ARG2H ; ARG1H * ARG2H -> ; PRODH:PRODL PRODH, RES3 ; PRODL, RES2 ; ; MOVF MULWF MOVF ADDWF MOVF ADDWFC CLRF ADDWFC ; MOVF MULWF MOVF ADDWF MOVF ADDWFC CLRF ADDWFC ; BTFSS BRA MOVF SUBWF MOVF SUBWFB ; SIGN_ARG1 BTFSS BRA MOVF SUBWF MOVF SUBWFB ; CONT_CODE : ARG1H, W ARG2L PRODL, W RES1, F PRODH, W RES2, F WREG, F RES3, F ARG2H, 7 SIGN_ARG1 ARG1L, W RES2 ARG1H, W RES3 ; ; ; ; ; ; ; ; ; ARG1H * ARG2L -> PRODH:PRODL Add cross products ARG1L, W ARG2H PRODL, RES1, PRODH, RES2, WREG, RES3, W F W F F F ; ; ; ; ; ; ; ; ARG1L * ARG2H -> PRODH:PRODL Add cross products
16 x 16 UNSIGNED MULTIPLY ROUTINE
EXAMPLE 6-4:
MOVF MULWF MOVFF MOVFF ; MOVF MULWF MOVFF MOVFF
16 x 16 SIGNED MULTIPLY ROUTINE
ARG1L, W ARG2L
; ARG1L * ARG2L -> ; PRODH:PRODL PRODH, RES1 ; PRODL, RES0 ;
ARG1L, W ARG2L
; ARG1L * ARG2L -> ; PRODH:PRODL PRODH, RES1 ; PRODL, RES0 ;
ARG1H, W ARG2H
; ARG1H * ARG2H -> ; PRODH:PRODL PRODH, RES3 ; PRODL, RES2 ;
Example 6-4 shows the sequence to do a 16 x 16 signed multiply. Equation 6-2 shows the algorithm used. The 32-bit result is stored in four registers, RES3:RES0. To account for the sign bits of the arguments, each argument pairs' Most Significant bit (MSb) is tested and the appropriate subtractions are done.
; ARG2H:ARG2L neg? ; no, check ARG1 ; ; ;
EQUATION 6-2:
16 x 16 SIGNED MULTIPLICATION ALGORITHM
RES3:RES0 = ARG1H:ARG1L * ARG2H:ARG2L = (ARG1H * ARG2H * 216)+ (ARG1H * ARG2L * 28)+ (ARG1L * ARG2H * 28)+ (ARG1L * ARG2L)+ (-1 * ARG2H<7> * ARG1H:ARG1L * 216)+ (-1 * ARG1H<7> * ARG2H:ARG2L * 216)
ARG1H, 7 CONT_CODE ARG2L, W RES2 ARG2H, W RES3
; ARG1H:ARG1L neg? ; no, done ; ; ;
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PIC18CXX2
7.0 INTERRUPTS
The PIC18CXX2 devices have multiple interrupt sources and an interrupt priority feature that allows each interrupt source to be assigned a high priority level, or a low priority level. The high priority interrupt vector is at 000008h and the low priority interrupt vector is at 000018h. High priority interrupt events will override any low priority interrupts that may be in progress. There are ten registers which are used to control interrupt operation. These registers are: * * * * * * * RCON INTCON INTCON2 INTCON3 PIR1, PIR2 PIE1, PIE2 IPR1, IPR2 When the IPEN bit is cleared (default state), the interrupt priority feature is disabled and interrupts are compatible with PICmicro(R) mid-range devices. In Compatibility mode, the interrupt priority bits for each source have no effect. INTCON<6> is the PEIE bit, which enables/disables all peripheral interrupt sources. INTCON<7> is the GIE bit, which enables/disables all interrupt sources. All interrupts branch to address 000008h in Compatibility mode. When an interrupt is responded to, the Global Interrupt Enable bit is cleared to disable further interrupts. If the IPEN bit is cleared, this is the GIE bit. If interrupt priority levels are used, this will be either the GIEH, or GIEL bit. High priority interrupt sources can interrupt a low priority interrupt. The return address is pushed onto the stack and the PC is loaded with the interrupt vector address (000008h or 000018h). Once in the Interrupt Service Routine, the source(s) of the interrupt can be determined by polling the interrupt flag bits. The interrupt flag bits must be cleared in software before re-enabling interrupts to avoid recursive interrupts. The "return from interrupt" instruction, RETFIE, exits the interrupt routine and sets the GIE bit (GIEH or GIEL if priority levels are used), which re-enables interrupts. For external interrupt events, such as the INT pins or the PORTB input change interrupt, the interrupt latency will be three to four instruction cycles. The exact latency is the same for one or two-cycle instructions. Individual interrupt flag bits are set, regardless of the status of their corresponding enable bit or the GIE bit.
It is recommended that the Microchip header files supplied with MPLAB(R) IDE be used for the symbolic bit names in these registers. This allows the assembler/ compiler to automatically take care of the placement of these bits within the specified register. Each interrupt source has three bits to control its operation. The functions of these bits are: * Flag bit to indicate that an interrupt event occurred * Enable bit that allows program execution to branch to the interrupt vector address when the flag bit is set * Priority bit to select high priority or low priority The interrupt priority feature is enabled by setting the IPEN bit (RCON<7>). When interrupt priority is enabled, there are two bits which enable interrupts globally. Setting the GIEH bit (INTCON<7>) enables all interrupts that have the priority bit set. Setting the GIEL bit (INTCON<6>) enables all interrupts that have the priority bit cleared. When the interrupt flag, enable bit and appropriate global interrupt enable bit are set, the interrupt will vector immediately to address 000008h or 000018h, depending on the priority level. Individual interrupts can be disabled through their corresponding enable bits.
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PIC18CXX2
FIGURE 7-1: INTERRUPT LOGIC
TMR0IF TMR0IE TMR0IP RBIF RBIE RBIP INT0IF INT0IE INT1IF INT1IE INT1IP INT2IF INT2IE INT2IP
Wake-up if in SLEEP mode
Peripheral Interrupt Flag bit Peripheral Interrupt Enable bit Peripheral Interrupt Priority bit TMR1IF TMR1IE TMR1IP XXXXIF XXXXIE XXXXIP Additional Peripheral Interrupts High Priority Interrupt Generation Low Priority Interrupt Generation
Interrupt to CPU Vector to location 0008h
GIEH/GIE IPE IPEN GIEL/PEIE IPEN
Peripheral Interrupt Flag bit Peripheral Interrupt Enable bit Peripheral Interrupt Priority bit TMR0IF TMR0IE TMR0IP RBIF RBIE RBIP INT0IF INT0IE Additional Peripheral Interrupts INT1IF INT1IE INT1IP INT2IF INT2IE INT2IP Interrupt to CPU Vector to Location 0018h
TMR1IF TMR1IE TMR1IP XXXXIF XXXXIE XXXXIP
GIEL\PEIE
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PIC18CXX2
7.1 INTCON Registers
The INTCON Registers are readable and writable registers, which contains various enable, priority, and flag bits.
REGISTER 7-1:
INTCON REGISTER
R/W-0 GIE/GIEH bit 7 R/W-0 PEIE/GIEL R/W-0 TMR0IE R/W-0 INT0IE R/W-0 RBIE R/W-0 TMR0IF R/W-0 INT0IF R/W-x RBIF bit 0
bit 7
GIE/GIEH: Global Interrupt Enable bit When IPEN = 0: 1 = Enables all unmasked interrupts 0 = Disables all interrupts When IPEN = 1: 1 = Enables all high priority interrupts 0 = Disables all high priority interrupts PEIE/GIEL: Peripheral Interrupt Enable bit When IPEN = 0: 1 = Enables all unmasked peripheral interrupts 0 = Disables all peripheral interrupts When IPEN = 1: 1 = Enables all low priority peripheral interrupts 0 = Disables all low priority peripheral interrupts TMR0IE: TMR0 Overflow Interrupt Enable bit 1 = Enables the TMR0 overflow interrupt 0 = Disables the TMR0 overflow interrupt INT0IE: INT0 External Interrupt Enable bit 1 = Enables the INT0 external interrupt 0 = Disables the INT0 external interrupt RBIE: RB Port Change Interrupt Enable bit 1 = Enables the RB port change interrupt 0 = Disables the RB port change interrupt TMR0IF: TMR0 Overflow Interrupt Flag bit 1 = TMR0 register has overflowed (must be cleared in software) 0 = TMR0 register did not overflow INT0IF: INT0 External Interrupt Flag bit 1 = The INT0 external interrupt occurred (must be cleared in software) 0 = The INT0 external interrupt did not occur RBIF: RB Port Change Interrupt Flag bit 1 = At least one of the RB7:RB4 pins changed state (must be cleared in software) 0 = None of the RB7:RB4 pins have changed state Legend: R = Readable bit - n = Value at POR reset W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
Note:
Interrupt flag bits are set when an interrupt condition occurs, regardless of the state of its corresponding enable bit, or the global enable bit. User software should ensure the appropriate interrupt flag bits are clear prior to enabling an interrupt. This feature allows for software polling.
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PIC18CXX2
REGISTER 7-2: INTCON2 REGISTER
R/W-1 RBPU bit 7 bit 7 RBPU: PORTB Pull-up Enable bit 1 = All PORTB pull-ups are disabled 0 = PORTB pull-ups are enabled by individual port latch values INTEDG0:External Interrupt0 Edge Select bit 1 = Interrupt on rising edge 0 = Interrupt on falling edge INTEDG1: External Interrupt1 Edge Select bit 1 = Interrupt on rising edge 0 = Interrupt on falling edge INTEDG2: External Interrupt2 Edge Select bit 1 = Interrupt on rising edge 0 = Interrupt on falling edge Unimplemented: Read as '0' TMR0IP: TMR0 Overflow Interrupt Priority bit 1 = High priority 0 = Low priority Unimplemented: Read as '0' RBIP: RB Port Change Interrupt Priority bit 1 = High priority 0 = Low priority Legend: R = Readable bit - n = Value at POR reset W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown R/W-1 INTEDG0 R/W-1 INTEDG1 R/W-1 INTEDG2 U-0 -- R/W-1 TMR0IP U-0 -- R/W-1 RBIP bit 0
bit 6
bit 5
bit 4
bit 3 bit 2
bit 1 bit 0
Note:
Interrupt flag bits are set when an interrupt condition occurs, regardless of the state of its corresponding enable bit, or the global enable bit. User software should ensure the appropriate interrupt flag bits are clear prior to enabling an interrupt. This feature allows for software polling.
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PIC18CXX2
REGISTER 7-3: INTCON3 REGISTER
R/W-1 INT2IP bit 7 bit 7 INT2IP: INT2 External Interrupt Priority bit 1 = High priority 0 = Low priority INT1IP: INT1 External Interrupt Priority bit 1 = High priority 0 = Low priority Unimplemented: Read as '0' INT2IE: INT2 External Interrupt Enable bit 1 = Enables the INT2 external interrupt 0 = Disables the INT2 external interrupt INT1IE: INT1 External Interrupt Enable bit 1 = Enables the INT1 external interrupt 0 = Disables the INT1 external interrupt Unimplemented: Read as '0' INT2IF: INT2 External Interrupt Flag bit 1 = The INT2 external interrupt occurred (must be cleared in software) 0 = The INT2 external interrupt did not occur INT1IF: INT1 External Interrupt Flag bit 1 = The INT1 external interrupt occurred (must be cleared in software) 0 = The INT1 external interrupt did not occur Legend: R = Readable bit - n = Value at POR reset W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown R/W-1 INT1IP U-0 -- R/W-0 INT2IE R/W-0 INT1IE U-0 -- R/W-0 INT2IF R/W-0 INT1IF bit 0
bit 6
bit 5 bit 4
bit 3
bit 2 bit 1
bit 0
Note:
Interrupt flag bits are set when an interrupt condition occurs, regardless of the state of its corresponding enable bit, or the global enable bit. User software should ensure the appropriate interrupt flag bits are clear prior to enabling an interrupt. This feature allows for software polling.
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7.2 PIR Registers
Note 1: Interrupt flag bits get set when an interrupt condition occurs, regardless of the state of its corresponding enable bit, or the global enable bit, GIE (INTCON<7>). 2: User software should ensure the appropriate interrupt flag bits are cleared prior to enabling an interrupt, and after servicing that interrupt. The PIR registers contain the individual flag bits for the peripheral interrupts. Due to the number of peripheral interrupt sources, there are two Peripheral Interrupt Flag Registers (PIR1, PIR2).
REGISTER 7-4:
PERIPHERAL INTERRUPT REQUEST (FLAG) REGISTER 1 (PIR1)
R/W-0 PSPIF bit 7 R/W-0 ADIF R-0 RCIF R-0 TXIF R/W-0 SSPIF R/W-0 CCP1IF R/W-0 TMR2IF R/W-0 TMR1IF bit 0
bit 7
PSPIF: Parallel Slave Port Read/Write Interrupt Flag bit 1 = A read or a write operation has taken place (must be cleared in software) 0 = No read or write has occurred ADIF: A/D Converter Interrupt Flag bit 1 = An A/D conversion completed (must be cleared in software) 0 = The A/D conversion is not complete RCIF: USART Receive Interrupt Flag bit 1 = The USART receive buffer, RCREG, is full (cleared when RCREG is read) 0 = The USART receive buffer is empty TXIF: USART Transmit Interrupt Flag bit 1 = The USART transmit buffer, TXREG, is empty (cleared when TXREG is written) 0 = The USART transmit buffer is full SSPIF: Master Synchronous Serial Port Interrupt Flag bit 1 = The transmission/reception is complete (must be cleared in software) 0 = Waiting to transmit/receive
bit 6
bit 5
bit 4
bit 3
bit 2
CCP1IF: CCP1 Interrupt Flag bit Capture mode: 1 = A TMR1 register capture occurred (must be cleared in software) 0 = No TMR1 register capture occurred Compare mode: 1 = A TMR1 register compare match occurred (must be cleared in software) 0 = No TMR1 register compare match occurred PWM mode: Unused in this mode TMR2IF: TMR2 to PR2 Match Interrupt Flag bit 1 = TMR2 to PR2 match occurred (must be cleared in software) 0 = No TMR2 to PR2 match occurred TMR1IF: TMR1 Overflow Interrupt Flag bit 1 = TMR1 register overflowed (must be cleared in software) 0 = MR1 register did not overflow Legend: R = Readable bit - n = Value at POR reset W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown
bit 1
bit 0
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PIC18CXX2
REGISTER 7-5: PERIPHERAL INTERRUPT REQUEST (FLAG) REGISTER 2 (PIR2)
U-0 -- bit 7 bit 7-4 bit 3 Unimplemented: Read as '0' BCLIF: Bus Collision Interrupt Flag bit 1 = A bus collision occurred (must be cleared in software) 0 = No bus collision occurred LVDIF: Low Voltage Detect Interrupt Flag bit 1 = A low voltage condition occurred (must be cleared in software) 0 = The device voltage is above the Low Voltage Detect trip point TMR3IF: TMR3 Overflow Interrupt Flag bit 1 = TMR3 register overflowed (must be cleared in software) 0 = TMR3 register did not overflow CCP2IF: CCPx Interrupt Flag bit Capture mode: 1 = A TMR1 register capture occurred (must be cleared in software) 0 = No TMR1 register capture occurred Compare mode: 1 = A TMR1 register compare match occurred (must be cleared in software) 0 = No TMR1 register compare match occurred PWM mode: Unused in this mode Legend: R = Readable bit - n = Value at POR reset W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown U-0 -- U-0 -- U-0 -- R/W-0 BCLIF R/W-0 LVDIF R/W-0 TMR3IF R/W-0 CCP2IF bit 0
bit 2
bit 1
bit 0
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7.3 PIE Registers
The PIE registers contain the individual enable bits for the peripheral interrupts. Due to the number of peripheral interrupt sources, there are two Peripheral Interrupt Enable Registers (PIE1, PIE2). When IPEN = 0, the PEIE bit must be set to enable any of these peripheral interrupts.
REGISTER 7-6:
PERIPHERAL INTERRUPT ENABLE REGISTER 1 (PIE1)
R/W-0 PSPIE bit 7 R/W-0 ADIE R/W-0 RCIE R/W-0 TXIE R/W-0 SSPIE R/W-0 CCP1IE R/W-0 TMR2IE R/W-0 TMR1IE bit 0
bit 7
PSPIE: Parallel Slave Port Read/Write Interrupt Enable bit 1 = Enables the PSP read/write interrupt 0 = Disables the PSP read/write interrupt ADIE: A/D Converter Interrupt Enable bit 1 = Enables the A/D interrupt 0 = Disables the A/D interrupt RCIE: USART Receive Interrupt Enable bit 1 = Enables the USART receive interrupt 0 = Disables the USART receive interrupt TXIE: USART Transmit Interrupt Enable bit 1 = Enables the USART transmit interrupt 0 = Disables the USART transmit interrupt SSPIE: Master Synchronous Serial Port Interrupt Enable bit 1 = Enables the MSSP interrupt 0 = Disables the MSSP interrupt CCP1IE: CCP1 Interrupt Enable bit 1 = Enables the CCP1 interrupt 0 = Disables the CCP1 interrupt TMR2IE: TMR2 to PR2 Match Interrupt Enable bit 1 = Enables the TMR2 to PR2 match interrupt 0 = Disables the TMR2 to PR2 match interrupt TMR1IE: TMR1 Overflow Interrupt Enable bit 1 = Enables the TMR1 overflow interrupt 0 = Disables the TMR1 overflow interrupt Legend: R = Readable bit - n = Value at POR W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
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PIC18CXX2
REGISTER 7-7: PERIPHERAL INTERRUPT ENABLE REGISTER 2 (PIE2)
U-0 -- bit 7 bit 7-4 bit 3 Unimplemented: Read as '0' BCLIE: Bus Collision Interrupt Enable bit 1 = Enabled 0 = Disabled LVDIE: Low Voltage Detect Interrupt Enable bit 1 = Enabled 0 = Disabled TMR3IE: TMR3 Overflow Interrupt Enable bit 1 = Enables the TMR3 overflow interrupt 0 = Disables the TMR3 overflow interrupt CCP2IE: CCP2 Interrupt Enable bit 1 = Enables the CCP2 interrupt 0 = Disables the CCP2 interrupt Legend: R = Readable bit - n = Value at POR W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown U-0 -- U-0 -- U-0 -- R/W-0 BCLIE R/W-0 LVDIE R/W-0 TMR3IE R/W-0 CCP2IE bit 0
bit 2
bit 1
bit 0
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7.4 IPR Registers
The IPR registers contain the individual priority bits for the peripheral interrupts. Due to the number of peripheral interrupt sources, there are two Peripheral Interrupt Priority Registers (IPR1, IPR2). The operation of the priority bits requires that the Interrupt Priority Enable (IPEN) bit be set.
REGISTER 7-8:
PERIPHERAL INTERRUPT PRIORITY REGISTER 1 (IPR1)
R/W-1 PSPIP bit 7 R/W-1 ADIP R/W-1 RCIP R/W-1 TXIP R/W-1 SSPIP R/W-1 CCP1IP R/W-1 TMR2IP R/W-1 TMR1IP bit 0
bit 7
PSPIP: Parallel Slave Port Read/Write Interrupt Priority bit 1 = High priority 0 = Low priority ADIP: A/D Converter Interrupt Priority bit 1 = High priority 0 = Low priority RCIP: USART Receive Interrupt Priority bit 1 = High priority 0 = Low priority TXIP: USART Transmit Interrupt Priority bit 1 = High priority 0 = Low priority
bit 6
bit 5
bit 4
bit 3
SSPIP: Master Synchronous Serial Port Interrupt Priority bit 1 = High priority 0 = Low priority CCP1IP: CCP1 Interrupt Priority bit 1 = High priority 0 = Low priority TMR2IP: TMR2 to PR2 Match Interrupt Priority bit 1 = High priority 0 = Low priority TMR1IP: TMR1 Overflow Interrupt Priority bit 1 = High priority 0 = Low priority Legend: R = Readable bit - n = Value at POR W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown
bit 2
bit 1
bit 0
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PIC18CXX2
REGISTER 7-9: PERIPHERAL INTERRUPT PRIORITY REGISTER 2 (IPR2)
U-0 -- bit 7 bit 7-4 bit 3 Unimplemented: Read as '0' BCLIP: Bus Collision Interrupt Priority bit 1 = High priority 0 = Low priority LVDIP: Low Voltage Detect Interrupt Priority bit 1 = High priority 0 = Low priority TMR3IP: TMR3 Overflow Interrupt Priority bit 1 = High priority 0 = Low priority CCP2IP: CCP2 Interrupt Priority bit 1 = High priority 0 = Low priority Legend: R = Readable bit - n = Value at POR W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown U-0 -- U-0 -- U-0 -- R/W-1 BCLIP R/W-1 LVDIP R/W-1 TMR3IP R/W-1 CCP2IP bit 0
bit 2
bit 1
bit 0
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7.5 RCON Register
The RCON register contains the bit which is used to enable prioritized interrupts (IPEN).
REGISTER 7-10:
RCON REGISTER
R/W-0 IPEN bit 7 R/W-0 LWRT U-0 -- R/W-1 RI R-1 TO R-1 PD R/W-0 POR R/W-0 BOR bit 0
bit 7
IPEN: Interrupt Priority Enable bit 1 = Enable priority levels on interrupts 0 = Disable priority levels on interrupts (16CXXX compatibility mode)
bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0
LWRT: Long Write Enable bit For details of bit operation, see Register 4-3 Unimplemented: Read as '0' RI: RESET Instruction Flag bit For details of bit operation, see Register 4-3 TO: Watchdog Time-out Flag bit For details of bit operation, see Register 4-3 PD: Power-down Detection Flag bit For details of bit operation, see Register 4-3 POR: Power-on Reset Status bit For details of bit operation, see Register 4-3 BOR: Brown-out Reset Status bit For details of bit operation, see Register 4-3 Legend: R = Readable bit - n = Value at POR reset W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown
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PIC18CXX2
7.6 INT0 Interrupt 7.7 TMR0 Interrupt
External interrupts on the RB0/INT0, RB1/INT1 and RB2/INT2 pins are edge triggered: either rising, if the corresponding INTEDGx bit is set in the INTCON2 register, or falling, if the INTEDGx bit is clear. When a valid edge appears on the RBx/INTx pin, the corresponding flag bit INTxF is set. This interrupt can be disabled by clearing the corresponding enable bit INTxE. Flag bit INTxF must be cleared in software in the Interrupt Service Routine before re-enabling the interrupt. All external interrupts (INT0, INT1 and INT2) can wake-up the processor from SLEEP, if bit INTxE was set prior to going into SLEEP. If the global interrupt enable bit GIE set, the processor will branch to the interrupt vector following wake-up. Interrupt priority for INT1 and INT2 is determined by the value contained in the interrupt priority bits, INT1IP (INTCON3<6>) and INT2IP (INTCON3<7>). There is no priority bit associated with INT0. It is always a high priority interrupt source. In 8-bit mode (which is the default), an overflow (FFh 00h) in the TMR0 register will set flag bit TMR0IF. In 16-bit mode, an overflow (FFFFh 0000h) in the TMR0H:TMR0L registers will set flag bit TMR0IF. The interrupt can be enabled/disabled by setting/clearing enable bit T0IE (INTCON<5>). Interrupt priority for Timer0 is determined by the value contained in the interrupt priority bit TMR0IP (INTCON2<2>). See Section 8.0 for further details on the Timer0 module.
7.8
PORTB Interrupt-on-Change
An input change on PORTB<7:4> sets flag bit RBIF (INTCON<0>). The interrupt can be enabled/disabled by setting/clearing enable bit, RBIE (INTCON<3>). Interrupt priority for PORTB Interrupt-on-change is determined by the value contained in the interrupt priority bit, RBIP (INTCON2<0>).
7.9
Context Saving During Interrupts
During an interrupt, the return PC value is saved on the stack. Additionally, the WREG, STATUS and BSR registers are saved on the fast return stack. If a fast return from interrupt is not used (see Section 4.3), the user may need to save the WREG, STATUS and BSR registers in software. Depending on the user's application, other registers may also need to be saved. Example 7-1 saves and restores the WREG, STATUS and BSR registers during an Interrupt Service Routine.
EXAMPLE 7-1:
MOVWF MOVFF MOVFF ; ; USER ; MOVFF MOVF MOVFF
SAVING STATUS, WREG AND BSR REGISTERS IN RAM
; W_TEMP is in virtual bank ; STATUS_TEMP located anywhere ; BSR located anywhere
W_TEMP STATUS, STATUS_TEMP BSR, BSR_TEMP ISR CODE BSR_TEMP, BSR W_TEMP, W STATUS_TEMP, STATUS
; Restore BSR ; Restore WREG ; Restore STATUS
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NOTES:
DS39026C-page 76
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PIC18CXX2
8.0 I/O PORTS
EXAMPLE 8-1:
CLRF PORTA ; ; ; ; ; ; ; ; ; ; ; ; ;
INITIALIZING PORTA
Initialize PORTA by clearing output data latches Alternate method to clear output data latches Configure A/D for digital inputs Value used to initialize data direction Set RA<3:0> as inputs RA<5:4> as outputs
Depending on the device selected, there are either five ports, or three ports available. Some pins of the I/O ports are multiplexed with an alternate function from the peripheral features on the device. In general, when a peripheral is enabled, that pin may not be used as a general purpose I/O pin. Each port has three registers for its operation. These registers are: * TRIS register (data direction register) * PORT register (reads the levels on the pins of the device) * LAT register (output latch) The data latch (LAT register) is useful for read-modifywrite operations on the value that the I/O pins are driving.
CLRF LATA
MOVLW 0x07 MOVWF ADCON1 MOVLW 0xCF
MOVWF TRISA
FIGURE 8-1:
8.1
PORTA, TRISA and LATA Registers
Data Bus
BLOCK DIAGRAM OF RA3:RA0 AND RA5 PINS
PORTA is a 6-bit wide, bi-directional port. The corresponding data direction register is TRISA. Setting a TRISA bit (= 1) will make the corresponding PORTA pin an input (i.e., put the corresponding output driver in a Hi-Impedance mode). Clearing a TRISA bit (= 0) will make the corresponding PORTA pin an output (i.e., put the contents of the output latch on the selected pin). Note: On a Power-on Reset, these pins are configured as digital inputs.
RD LATA D Q VDD WR LATA or PORTA CK Q P
Data Latch D Q N I/O pin(1)
Reading the PORTA register reads the status of the pins, whereas writing to it will write to the port latch. The Data Latch register (LATA) is also memory mapped. Read-modify-write operations on the LATA register reads and writes the latched output value for PORTA. The RA4 pin is multiplexed with the Timer0 module clock input to become the RA4/T0CKI pin. The RA4/ T0CKI pin is a Schmitt Trigger input and an open drain output. All other RA port pins have TTL input levels and full CMOS output drivers. The other PORTA pins are multiplexed with analog inputs and the analog VREF+ and VREF- inputs. The operation of each pin is selected by clearing/setting the control bits in the ADCON1 register (A/D Control Register1). Note: On a Power-on Reset, these pins are configured as analog inputs and read as '0'.
WR TRISA CK Q TRIS Latch
VSS Analog Input Mode
RD TRISA Q D
TTL Input Buffer
EN RD PORTA SS Input (RA5 only) To A/D Converter and LVD Modules
Note 1: I/O pins have protection diodes to VDD and VSS.
The TRISA register controls the direction of the RA pins, even when they are being used as analog inputs. The user must ensure the bits in the TRISA register are maintained set when using them as analog inputs.
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FIGURE 8-2: BLOCK DIAGRAM OF RA4/T0CKI PIN FIGURE 8-3:
ECRA6 or RCRA6 Enable Data Bus RD LATA Data Bus WR LATA or PORTA RD LATA
D Q Q
BLOCK DIAGRAM OF RA6
CK
D N VSS Schmitt Trigger Input Buffer I/O pin
(1)
Q VDD
Data Latch
D Q Q
WR LATA or PORTA
CK
Q
P
Data Latch D WR TRISA Q N I/O pin(1)
WR TRISA
CK
TRIS Latch
CK
Q ECRA6 or RCRA6 Enable
VSS
TRIS Latch RD TRISA Q D RD TRISA EN EN RD PORTA Data Bus TMR0 Clock Input Note 1: I/O pins have protection diodes to VDD and VSS. RD PORTA
Data Bus
TTL Input Buffer
Q
D
EN
Note 1: I/O pins have protection diodes to VDD and VSS.
DS39026C-page 78
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PIC18CXX2
TABLE 8-1:
Name RA0/AN0 RA1/AN1 RA2/AN2/VREFRA3/AN3/VREF+ RA4/T0CKI RA5/SS/AN4/LVDIN OSC2/CLKO/RA6
PORTA FUNCTIONS
Bit# bit0 bit1 bit2 bit3 bit4 bit5 bit6 Buffer TTL TTL TTL TTL ST TTL TTL Input/output or analog input. Input/output or analog input. Input/output or analog input or VREF-. Input/output or analog input or VREF+. Input/output or external clock input for Timer0. Output is open drain type. Input/output or slave select input for synchronous serial port or analog input, or low voltage detect input. OSC2 or clock output or I/O pin. Function
Legend: TTL = TTL input, ST = Schmitt Trigger input
TABLE 8-2:
Name PORTA LATA TRISA ADCON1
SUMMARY OF REGISTERS ASSOCIATED WITH PORTA
Bit 7 -- -- -- Bit 6 RA6 Bit 5 RA5 Bit 4 RA4 Bit 3 RA3 Bit 2 RA2 Bit 1 RA1 Bit 0 RA0 Value on POR, BOR Value on all other RESETS
--0x 0000 --0u 0000 --xx xxxx --uu uuuu --11 1111 --11 1111
Latch A Data Output Register PORTA Data Direction Register -- -- PCFG3 PCFG2 PCFG1 PCFG0
ADFM ADCS2
--0- 0000 --0- 0000
Legend: x = unknown, u = unchanged, - = unimplemented locations read as '0'. Shaded cells are not used by PORTA.
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8.2 PORTB, TRISB and LATB Registers
A mismatch condition will continue to set flag bit RBIF. Reading PORTB will end the mismatch condition and allow flag bit RBIF to be cleared. The interrupt-on-change feature is recommended for wake-up on key depression operation and operations where PORTB is only used for the interrupt-on-change feature. Polling of PORTB is not recommended while using the interrupt-on-change feature. RB3 can be configured by the configuration bit CCP2MX as the alternate peripheral pin for the CCP2 module (CCP2MX = `0').
PORTB is an 8-bit wide, bi-directional port. The corresponding data direction register is TRISB. Setting a TRISB bit (= 1) will make the corresponding PORTB pin an input (i.e., put the corresponding output driver in a Hi-Impedance mode). Clearing a TRISB bit (= 0) will make the corresponding PORTB pin an output (i.e., put the contents of the output latch on the selected pin). Note: On a Power-on Reset, these pins are configured as digital inputs.
The Data Latch register (LATB) is also memory mapped. Read-modify-write operations on the LATB register reads and writes the latched output value for PORTB.
FIGURE 8-4:
BLOCK DIAGRAM OF RB7:RB4 PINS
VDD Weak P Pull-up Data Latch D CK TRIS Latch D Q TTL Input Buffer Q I/O pin(1)
RBPU(2)
EXAMPLE 8-2:
CLRF PORTB ; ; ; ; ; ; ; ; ; ; ; ;
INITIALIZING PORTB
Initialize PORTB by clearing output data latches Alternate method to clear output data latches Value used to initialize data direction Set RB<3:0> as inputs RB<5:4> as outputs RB<7:6> as inputs
Data Bus WR LATB or PORTB
CLRF
LATB
MOVLW 0xCF
WR TRISB
CK
ST Buffer
MOVWF TRISB
RD TRISB
Each of the PORTB pins has a weak internal pull-up. A single control bit can turn on all the pull-ups. This is performed by clearing bit RBPU (INTCON2<7>). The weak pull-up is automatically turned off when the port pin is configured as an output. The pull-ups are disabled on a Power-on Reset. Four of the PORTB pins, RB7:RB4, have an interrupton-change feature. Only pins configured as inputs can cause this interrupt to occur (i.e., any RB7:RB4 pin configured as an output is excluded from the interrupton-change comparison). The input pins (of RB7:RB4) are compared with the old value latched on the last read of PORTB. The "mismatch" outputs of RB7:RB4 are OR'ed together to generate the RB Port Change Interrupt with flag bit RBIF (INTCON<0>). This interrupt can wake the device from SLEEP. The user, in the Interrupt Service Routine, can clear the interrupt in the following manner: a) Any read or write of PORTB (except with the MOVFF instruction). This will end the mismatch condition. Clear flag bit RBIF.
RD LATB Q RD PORTB
Latch D EN Q1
Set RBIF
Q From other RB7:RB4 pins RBx/INTx
D RD PORTB EN Q3
Note 1: I/O pins have diode protection to VDD and VSS. 2: To enable weak pull-ups, set the appropriate TRIS bit(s) and clear the RBPU bit (INTCON2<7>).
b)
DS39026C-page 80
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PIC18CXX2
FIGURE 8-5: BLOCK DIAGRAM OF RB2:RB0 PINS
VDD RBPU(2) Data Latch Data Bus WR Port D CK TRIS Latch D WR TRIS CK Q TTL Input Buffer Q I/O pin(1) Weak P Pull-up
RD TRIS Q RD Port D EN
RB0/INT Schmitt Trigger Buffer RD Port
Note 1: I/O pins have diode protection to VDD and VSS. 2: To enable weak pull-ups, set the appropriate TRIS bit(s) and clear the RBPU bit (OPTION_REG<7>).
FIGURE 8-6:
BLOCK DIAGRAM OF RB3
VDD RBPU
(2)
CCP2MX CCP Output(3) 1 VDD P 0 Enable CCP Output(3) Data Bus WR LATB or WR PORTB Data Latch D CK TRIS Latch D WR TRISB CK Q Q N VSS
Weak P Pull-up
I/O pin(1)
TTL Input Buffer
RD TRISB RD LATB Q RD PORTB D EN
RD PORTB CCP2 Input(3) Schmitt Trigger Buffer CCP2MX = 0 Note 1: I/O pin has diode protection to VDD and VSS. 2: To enable weak pull-ups, set the appropriate DDR bit(s) and clear the RBPU bit (INTCON2<7>). 3: The CCP2 input/output is multiplexed with RB3, if the CCP2MX bit is enabled (='0') in the configuration register.
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TABLE 8-3:
Name RB0/INT0 RB1/INT1 RB2/INT2 RB3/CCP2(3)
PORTB FUNCTIONS
Bit# bit0 bit1 bit2 bit3 Buffer TTL/ST(1) TTL/ST(1) TTL/ST(1) TTL/ST(4) Function Input/output pin or external interrupt input1. Internal software programmable weak pull-up. Input/output pin or external interrupt input2. Internal software programmable weak pull-up. Input/output pin or external interrupt input3. Internal software programmable weak pull-up. Input/output pin. Capture2 input/Compare2 output/PWM output when CCP2MX configuration bit is enabled. Internal software programmable weak pull-up. Input/output pin (with interrupt-on-change). Internal software programmable weak pull-up. Input/output pin (with interrupt-on-change). Internal software programmable weak pull-up. Input/output pin (with interrupt-on-change). Internal software programmable weak pull-up. Serial programming clock. Input/output pin (with interrupt-on-change). Internal software programmable weak pull-up. Serial programming data.
RB4 RB5 RB6 RB7 Legend: Note 1: 2: 3: 4:
bit4 bit5 bit6 bit7
TTL TTL TTL/ST(2) TTL/ST(2)
TTL = TTL input, ST = Schmitt Trigger input This buffer is a Schmitt Trigger input when configured as the external interrupt. This buffer is a Schmitt Trigger input when used in Serial Programming mode. A device configuration bit selects which I/O pin the CCP2 pin is multiplexed on. This buffer is a Schmitt Trigger input when configured as the CCP2 input.
TABLE 8-4:
Name PORTB LATB TRISB INTCON INTCON2 INTCON3
SUMMARY OF REGISTERS ASSOCIATED WITH PORTB
Bit 7 RB7 Bit 6 RB6 Bit 5 RB5 Bit 4 RB4 Bit 3 RB3 Bit 2 RB2 Bit 1 RB1 Bit 0 RB0 Value on POR, BOR
xxxx xxxx
Value on all other RESETS
uuuu uuuu
LATB Data Output Register PORTB Data Direction Register GIE/ GIEH RBPU INT2IP PEIE/ GIEL INTEDG0 INT1IP TMR0IE INTEDG1 -- INT0IE INTEDG2 INT2IE RBIE -- INT1IE TMR0IF TMR0IP -- INT0IF -- INT2IF RBIF RBIP INT1IF
1111 1111 0000 000x 1111 -1-1 11-0 0-00 1111 1111 0000 000u 1111 -1-1 11-0 0-00
Legend: x = unknown, u = unchanged. Shaded cells are not used by PORTB.
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PIC18CXX2
8.3 PORTC, TRISC and LATC Registers
The pin override value is not loaded into the TRIS register. This allows read-modify-write of the TRIS register, without concern due to peripheral overrides. RC1 is normally configured by the configuration bit CCP2MX as the default peripheral pin for the CCP2 module (default/erased state, CCP2MX = `1').
PORTC is an 8-bit wide, bi-directional port. The corresponding Data Direction Register is TRISC. Setting a TRISC bit (= 1) will make the corresponding PORTC pin an input (i.e., put the corresponding output driver in a Hi-Impedance mode). Clearing a TRISC bit (= 0) will make the corresponding PORTC pin an output (i.e., put the contents of the output latch on the selected pin). Note: On a Power-on Reset, these pins are configured as digital inputs.
EXAMPLE 8-3:
CLRF PORTC ; ; ; ; ; ; ; ; ; ; ; ;
INITIALIZING PORTC
Initialize PORTC by clearing output data latches Alternate method to clear output data latches Value used to initialize data direction Set RC<3:0> as inputs RC<5:4> as outputs RC<7:6> as inputs
CLRF
LATC
The Data Latch register (LATC) is also memory mapped. Read-modify-write operations on the LATC register reads and writes the latched output value for PORTC. PORTC is multiplexed with several peripheral functions (Table 8-5). PORTC pins have Schmitt Trigger input buffers. When enabling peripheral functions, care should be taken in defining TRIS bits for each PORTC pin. Some peripherals override the TRIS bit to make a pin an output, while other peripherals override the TRIS bit to make a pin an input. The user should refer to the corresponding peripheral section for the correct TRIS bit settings.
MOVLW 0xCF
MOVWF TRISC
FIGURE 8-7:
PORTC BLOCK DIAGRAM (PERIPHERAL OUTPUT OVERRIDE)
Port/Peripheral Select(2) VDD Peripheral Data Out
RD LATC Data Bus WR LATC or WR PORTC Data Latch D CK Q Q
1 0
P I/O pin(1)
DDR Latch D Q WR TRISC CK Q N Schmitt Trigger
RD TRISC Peripheral Output Enable(3) Q RD PORTC Peripheral Data In Note 1: I/O pins have diode protection to VDD and VSS. 2: Port/Peripheral select signal selects between port data (input) and peripheral output. 3: Peripheral Output Enable is only active if peripheral select is active. D EN
VSS
2001 Microchip Technology Inc.
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PIC18CXX2
TABLE 8-5:
Name RC0/T1OSO/T1CKI RC1/T1OSI/CCP2
PORTC FUNCTIONS
Bit# bit0 bit1 Buffer Type ST ST Function Input/output port pin or Timer1 oscillator output/Timer1 clock input. Input/output port pin, Timer1 oscillator input, or Capture2 input/ Compare2 output/PWM output when CCP2MX configuration bit is disabled. Input/output port pin or Capture1 input/Compare1 output/ PWM1 output. RC3 can also be the synchronous serial clock for both SPI and I2C modes. RC4 can also be the SPI Data In (SPI mode) or Data I/O (I2C mode). Input/output port pin or Synchronous Serial Port Data output. Input/output port pin, Addressable USART Asynchronous Transmit, or Addressable USART Synchronous Clock. Input/output port pin, Addressable USART Asynchronous Receive, or Addressable USART Synchronous Data.
RC2/CCP1 RC3/SCK/SCL RC4/SDI/SDA RC5/SDO RC6/TX/CK RC7/RX/DT
bit2 bit3 bit4 bit5 bit6 bit7
ST ST ST ST ST ST
Legend: ST = Schmitt Trigger input
TABLE 8-6:
Name PORTC LATC TRISC
SUMMARY OF REGISTERS ASSOCIATED WITH PORTC
Bit 7 RC7 Bit 6 RC6 Bit 5 RC5 Bit 4 RC4 Bit 3 RC3 Bit 2 RC2 Bit 1 RC1 Bit 0 RC0 Value on POR, BOR xxxx xxxx xxxx xxxx 1111 1111 Value on all other RESETS uuuu uuuu uuuu uuuu 1111 1111
LATC Data Output Register PORTC Data Direction Register
Legend: x = unknown, u = unchanged
DS39026C-page 84
2001 Microchip Technology Inc.
PIC18CXX2
8.4 PORTD, TRISD and LATD Registers
FIGURE 8-8: PORTD BLOCK DIAGRAM IN I/O PORT MODE
This section is only applicable to the PIC18C4X2 devices. PORTD is an 8-bit wide, bi-directional port. The corresponding Data Direction register is TRISD. Setting a TRISD bit (= 1) will make the corresponding PORTD pin an input (i.e., put the corresponding output driver in a Hi-Impedance mode). Clearing a TRISD bit (= 0) will make the corresponding PORTD pin an output (i.e., put the contents of the output latch on the selected pin). Note: On a Power-on Reset, these pins are configured as digital inputs.
Data Bus WR LATD or PORTD RD LATD D Q I/O pin(1) CK Data Latch D WR TRISD Q Schmitt Trigger Input Buffer
CK TRIS Latch
The Data Latch register (LATD) is also memory mapped. Read-modify-write operations on the LATD register reads and writes the latched output value for PORTD. PORTD is an 8-bit port with Schmitt Trigger input buffers. Each pin is individually configurable as an input or output. PORTD can be configured as an 8-bit wide microprocessor port (parallel slave port) by setting control bit PSPMODE (TRISE<4>). In this mode, the input buffers are TTL. See Section 8.6 for additional information on the Parallel Slave Port (PSP).
RD PORTD
RD TRISD Q D EN EN
Note 1: I/O pins have diode protection to VDD and VSS.
EXAMPLE 8-4:
CLRF PORTD ; ; ; ; ; ; ; ; ; ; ; ;
INITIALIZING PORTD
Initialize PORTD by clearing output data latches Alternate method to clear output data latches Value used to initialize data direction Set RD<3:0> as inputs RD<5:4> as outputs RD<7:6> as inputs
CLRF
LATD
MOVLW 0xCF
MOVWF TRISD
2001 Microchip Technology Inc.
DS39026C-page 85
PIC18CXX2
TABLE 8-7:
Name RD0/PSP0 RD1/PSP1 RD2/PSP2 RD3/PSP3 RD4/PSP4 RD5/PSP5 RD6/PSP6 RD7/PSP7
PORTD FUNCTIONS
Bit# bit0 bit1 bit2 bit3 bit4 bit5 bit6 bit7 Buffer Type ST/TTL(1) ST/TTL(1) ST/TTL(1) ST/TTL ST/TTL
(1)
Function Input/output port pin or parallel slave port bit0. Input/output port pin or parallel slave port bit1. Input/output port pin or parallel slave port bit2. Input/output port pin or parallel slave port bit3. Input/output port pin or parallel slave port bit4. Input/output port pin or parallel slave port bit5. Input/output port pin or parallel slave port bit6. Input/output port pin or parallel slave port bit7.
ST/TTL(1)
(1)
ST/TTL(1) ST/TTL(1)
Legend: ST = Schmitt Trigger input, TTL = TTL input Note 1: Input buffers are Schmitt Triggers when in I/O mode and TTL buffers when in Parallel Slave Port mode.
TABLE 8-8:
Name PORTD LATD TRISD TRISE Bit 7 RD7
SUMMARY OF REGISTERS ASSOCIATED WITH PORTD
Bit 6 RD6 Bit 5 RD5 Bit 4 RD4 Bit 3 RD3 Bit 2 RD2 Bit 1 RD1 Bit 0 RD0 Value on POR, BOR xxxx xxxx xxxx xxxx 1111 1111 -- PORTE Data Direction bits 0000 -111 Value on all other RESETS uuuu uuuu uuuu uuuu 1111 1111 0000 -111
LATD Data Output Register PORTD Data Direction Register IBF OBF IBOV PSPMODE
Legend: x = unknown, u = unchanged, - = unimplemented, read as '0'. Shaded cells are not used by PORTD.
DS39026C-page 86
2001 Microchip Technology Inc.
PIC18CXX2
8.5 PORTE, TRISE and LATE Registers
FIGURE 8-9: PORTE BLOCK DIAGRAM IN I/O PORT MODE
This section is only applicable to the PIC18C4X2 devices. PORTE is a 3-bit wide, bi-directional port. The corresponding Data Direction register is TRISE. Setting a TRISE bit (= 1) will make the corresponding PORTE pin an input (i.e., put the corresponding output driver in a Hi-Impedance mode). Clearing a TRISE bit (= 0) will make the corresponding PORTE pin an output (i.e., put the contents of the output latch on the selected pin). Note: On a Power-on Reset, these pins are configured as digital inputs.
RD LATE Data Bus WR LATE or PORTE D Q I/O pin(1) CK Data Latch D WR TRISE Q Schmitt Trigger Input Buffer
CK TRIS Latch
The Data Latch register (LATE) is also memory mapped. Read-modify-write operations on the LATE register reads and writes the latched output value for PORTE. PORTE has three pins (RE0/RD/AN5, RE1/WR/AN6 and RE2/CS/AN7), which are individually configurable as inputs or outputs. These pins have Schmitt Trigger input buffers. Register 8-1 shows the TRISE register, which also controls the parallel slave port operation. PORTE pins are multiplexed with analog inputs. When selected as an analog input, these pins will read as '0's. TRISE controls the direction of the RE pins, even when they are being used as analog inputs. The user must make sure to keep the pins configured as inputs when using them as analog inputs.
RD PORTE
RD TRISE Q D EN EN
To Analog Converter
Note 1: I/O pins have diode protection to VDD and VSS.
Note:
On a Power-on Reset, these pins are configured as analog inputs.
EXAMPLE 8-5:
CLRF PORTE ; ; ; ; ; ; ; ; ; ; ; ; ; ;
INITIALIZING PORTE
Initialize PORTE by clearing output data latches Alternate method to clear output data latches Configure A/D for digital inputs Value used to initialize data direction Set RE<0> as inputs RE<1> as outputs RE<2> as inputs
CLRF
LATE
MOVLW MOVWF MOVLW
0x07 ADCON1 0x03
MOVWF
TRISC
2001 Microchip Technology Inc.
DS39026C-page 87
PIC18CXX2
REGISTER 8-1: TRISE REGISTER
R-0 IBF bit 7 bit 7 IBF: Input Buffer Full Status bit 1 = A word has been received and waiting to be read by the CPU 0 = No word has been received OBF: Output Buffer Full Status bit 1 = The output buffer still holds a previously written word 0 = The output buffer has been read IBOV: Input Buffer Overflow Detect bit (in Microprocessor mode) 1 = A write occurred when a previously input word has not been read (must be cleared in software) 0 = No overflow occurred PSPMODE: Parallel Slave Port Mode Select bit 1 = Parallel Slave Port mode 0 = General purpose I/O mode Unimplemented: Read as '0' TRISE2: RE2 Direction Control bit 1 = Input 0 = Output TRISE1: RE1 Direction Control bit 1 = Input 0 = Output TRISE0: RE0 Direction Control bit 1 = Input 0 = Output Legend: R = Readable bit - n = Value at POR W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown R-0 OBF R/W-0 IBOV R/W-0 PSPMODE U-0 -- R/W-1 TRISE2 R/W-1 TRISE1 R/W-1 TRISE0 bit 0
bit 6
bit 5
bit 4
bit 3 bit 2
bit 1
bit 0
DS39026C-page 88
2001 Microchip Technology Inc.
PIC18CXX2
TABLE 8-9:
Name
PORTE FUNCTIONS
Bit# Buffer Type Function Input/output port pin or read control input in Parallel Slave Port mode or analog input: RD 1 = Not a read operation 0 = Read operation. Reads PORTD register (if chip selected). Input/output port pin or write control input in Parallel Slave Port mode or analog input: WR 1 = Not a write operation 0 = Write operation. Writes PORTD register (if chip selected). Input/output port pin or chip select control input in Parallel Slave Port mode or analog input: CS 1 = Device is not selected 0 = Device is selected
RE0/RD/AN5
bit0
ST/TTL(1)
RE1/WR/AN6
bit1
ST/TTL(1)
RE2/CS/AN7
bit2
ST/TTL(1)
Legend: ST = Schmitt Trigger input, TTL = TTL input Note 1: Input buffers are Schmitt Triggers when in I/O mode and TTL buffers when in Parallel Slave Port mode.
TABLE 8-10:
Name PORTE LATE TRISE ADCON1 Bit 7 -- -- IBF ADFM
SUMMARY OF REGISTERS ASSOCIATED WITH PORTE
Bit 6 -- -- OBF ADCS2 Bit 5 -- -- IBOV -- Bit 4 -- -- PSPMODE -- Bit 3 -- -- -- PCFG3 Bit 2 RE2 Bit 1 RE1 Bit 0 RE0 Value on POR, BOR
---- -000 ---- -xxx 0000 -111 --0- -000
Value on all other RESETS
---- -000 ---- -uuu 0000 -111 --0- -000
LATE Data Output Register PORTE Data Direction bits PCFG2 PCFG1 PCFG0
Legend: x = unknown, u = unchanged, - = unimplemented, read as '0'. Shaded cells are not used by PORTE.
2001 Microchip Technology Inc.
DS39026C-page 89
PIC18CXX2
8.6 Parallel Slave Port
FIGURE 8-10:
The Parallel Slave Port is implemented on the 40-pin devices only (PIC18C4X2). PORTD operates as an 8-bit wide, parallel slave port, or microprocessor port, when control bit PSPMODE (TRISE<4>) is set. It is asynchronously readable and writable by the external world through RD control input pin RE0/RD and WR control input pin RE1/WR. It can directly interface to an 8-bit microprocessor data bus. The external microprocessor can read or write the PORTD latch as an 8-bit latch. Setting bit PSPMODE enables port pin RE0/RD to be the RD input, RE1/WR to be the WR input and RE2/CS to be the CS (chip select) input. For this functionality, the corresponding data direction bits of the TRISE register (TRISE<2:0>) must be configured as inputs (set). The A/D port configuration bits PCFG2:PCFG0 (ADCON1<2:0>) must be set, which will configure pins RE2:RE0 as digital I/O. A write to the PSP occurs when both the CS and WR lines are first detected low. A read from the PSP occurs when both the CS and RD lines are first detected low. The PORTE I/O pins become control inputs for the microprocessor port when bit PSPMODE (TRISE<4>) is set. In this mode, the user must make sure that the TRISE<2:0> bits are set (pins are configured as digital inputs), and the ADCON1 is configured for digital I/O. In this mode, the input buffers are TTL.
PORTD AND PORTE BLOCK DIAGRAM (PARALLEL SLAVE PORT)
Data Bus
D Q
WR LATD or PORTD
CK
RDx pin TTL
Data Latch Q D EN EN
RD PORTD
RD LATD
One bit of PORTD Set Interrupt Flag PSPIF (PIR1<7>)
Read
TTL
RD
Chip Select TTL Write TTL
CS
WR
Note: I/O pin has protection diodes to VDD and VSS.
FIGURE 8-11:
PARALLEL SLAVE PORT WRITE WAVEFORMS
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
CS WR RD PORTD<7:0> IBF OBF PSPIF
DS39026C-page 90
2001 Microchip Technology Inc.
PIC18CXX2
FIGURE 8-12: PARALLEL SLAVE PORT READ WAVEFORMS
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
CS WR RD PORTD<7:0> IBF OBF PSPIF
TABLE 8-11:
Name PORTD LATD TRISD PORTE LATE TRISE INTCON PIR1 PIE1 IPR1 ADCON1 Bit 7
REGISTERS ASSOCIATED WITH PARALLEL SLAVE PORT
Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on POR, BOR
xxxx xxxx xxxx xxxx 1111 1111
Value on all other RESETS
uuuu uuuu uuuu uuuu 1111 1111 ---- -000 ---- -uuu 0000 -111 0000 000u 0000 0000 0000 0000 0000 0000 --0- -000
Port Data Latch when written; Port pins when read LATD Data Output bits PORTD Data Direction bits -- -- IBF GIE/ GIEH PSPIF PSPIE PSPIP ADFM -- -- OBF PEIE/ GIEL ADIF ADIE ADIP ADCS2 -- -- IBOV TMR0IF RCIF RCIE RCIP -- -- -- PSPMODE INT0IE TXIF TXIE TXIP -- -- -- -- RBIE SSPIF SSPIE SSPIP PCFG3 RE2 RE1 RE0 LATE Data Output bits PORTE Data Direction bits TMR0IF CCP1IF CCP1IE CCP1IP PCFG2 INT0IF TMR2IF TMR2IE TMR2IP PCFG1 RBIF TMR1IF TMR1IE TMR1IP PCFG0
---- -000 ---- -xxx 0000 -111 0000 000x 0000 0000 0000 0000 0000 0000 --0- -000
Legend: x = unknown, u = unchanged, - = unimplemented, read as '0'. Shaded cells are not used by the Parallel Slave Port.
2001 Microchip Technology Inc.
DS39026C-page 91
PIC18CXX2
NOTES:
DS39026C-page 92
2001 Microchip Technology Inc.
PIC18CXX2
9.0 TIMER0 MODULE
The Timer0 module has the following features: * Software selectable as an 8-bit or 16-bit timer/ counter * Readable and writable * Dedicated 8-bit software programmable prescaler * Clock source selectable to be external or internal * Interrupt-on-overflow from FFh to 00h in 8-bit mode and FFFFh to 0000h in 16-bit mode * Edge select for external clock Figure 9-1 shows a simplified block diagram of the Timer0 module in 8-bit mode and Figure 9-2 shows a simplified block diagram of the Timer0 module in 16-bit mode. The T0CON register (Register 9-1) is a readable and writable register that controls all the aspects of Timer0, including the prescale selection.
REGISTER 9-1:
T0CON: TIMER0 CONTROL REGISTER
R/W-1 TMR0ON bit 7 R/W-1 T08BIT R/W-1 T0CS R/W-1 T0SE R/W-1 PSA R/W-1 T0PS2 R/W-1 T0PS1 R/W-1 T0PS0 bit 0
bit 7
TMR0ON: Timer0 On/Off Control bit 1 = Enables Timer0 0 = Stops Timer0 T08BIT: Timer0 8-bit/16-bit Control bit 1 = Timer0 is configured as an 8-bit timer/counter 0 = Timer0 is configured as a 16-bit timer/counter T0CS: Timer0 Clock Source Select bit 1 = Transition on T0CKI pin 0 = Internal instruction cycle clock (CLKOUT) T0SE: Timer0 Source Edge Select bit 1 = Increment on high-to-low transition on T0CKI pin 0 = Increment on low-to-high transition on T0CKI pin PSA: Timer0 Prescaler Assignment bit 1 = TImer0 prescaler is NOT assigned. Timer0 clock input bypasses prescaler. 0 = Timer0 prescaler is assigned. Timer0 clock input comes from prescaler output. T0PS2:T0PS0: Timer0 Prescaler Select bits 111 = 1:256 prescale value 110 = 1:128 prescale value 101 = 1:64 prescale value 100 = 1:32 prescale value 011 = 1:16 prescale value 010 = 1:8 prescale value 001 = 1:4 prescale value 000 = 1:2 prescale value Legend: R = Readable bit - n = Value at POR reset W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown
bit 6
bit 5
bit 4
bit 3
bit 2:0
2001 Microchip Technology Inc.
DS39206C-page 93
PIC18CXX2
FIGURE 9-1: TIMER0 BLOCK DIAGRAM IN 8-BIT MODE
Data Bus FOSC/4 0 8 0 1 RA4/T0CKI pin T0SE Programmable Prescaler 1 Sync with Internal Clocks (2 TCY delay) TMR0
3
T0PS2, T0PS1, T0PS0 T0CS
PSA
Set Interrupt Flag bit TMR0IF on Overflow
Note:
Upon RESET, Timer0 is enabled in 8-bit mode with clock input from T0CKI max. prescale.
FIGURE 9-2:
TIMER0 BLOCK DIAGRAM IN 16-BIT MODE
FOSC/4
0 0 1 Sync with Internal Clocks (2 TCY delay) TMR0L TMR0 High Byte 8 Set Interrupt Flag bit TMR0IF on Overflow
T0CKI pin T0SE
Programmable Prescaler 3
1
T0PS2, T0PS1, T0PS0 T0CS PSA 8 8 TMR0H 8
Read TMR0L Write TMR0L
Data Bus<7:0>
Note:
Upon RESET, Timer0 is enabled in 8-bit mode with clock input from T0CKI max. prescale.
DS39206C-page 94
2001 Microchip Technology Inc.
PIC18CXX2
9.1 Timer0 Operation
9.2.1 SWITCHING PRESCALER ASSIGNMENT Timer0 can operate as a timer or as a counter. Timer mode is selected by clearing the T0CS bit. In Timer mode, the Timer0 module will increment every instruction cycle (without prescaler). If the TMR0 register is written, the increment is inhibited for the following two instruction cycles. The user can work around this by writing an adjusted value to the TMR0 register. Counter mode is selected by setting the T0CS bit. In Counter mode, Timer0 will increment either on every rising, or falling edge of pin RA4/T0CKI. The incrementing edge is determined by the Timer0 Source Edge Select bit (T0SE). Clearing the T0SE bit selects the rising edge. Restrictions on the external clock input are discussed below. When an external clock input is used for Timer0, it must meet certain requirements. The requirements ensure the external clock can be synchronized with the internal phase clock (TOSC). Also, there is a delay in the actual incrementing of Timer0 after synchronization. The prescaler assignment is fully under software control (i.e., it can be changed "on-the-fly" during program execution).
9.3
Timer0 Interrupt
The TMR0 interrupt is generated when the TMR0 register overflows from FFh to 00h in 8-bit mode, or FFFFh to 0000h in 16-bit mode. This overflow sets the TMR0IF bit. The interrupt can be masked by clearing the TMR0IE bit. The TMR0IE bit must be cleared in software by the Timer0 module Interrupt Service Routine before re-enabling this interrupt. The TMR0 interrupt cannot awaken the processor from SLEEP, since the timer is shut-off during SLEEP.
9.4
16-Bit Mode Timer Reads and Writes
9.2
Prescaler
An 8-bit counter is available as a prescaler for the Timer0 module. The prescaler is not readable or writable. The PSA and T0PS2:T0PS0 bits determine the prescaler assignment and prescale ratio. Clearing bit PSA will assign the prescaler to the Timer0 module. When the prescaler is assigned to the Timer0 module, prescale values of 1:2, 1:4,..., 1:256 are selectable. When assigned to the Timer0 module, all instructions writing to the TMR0 register (e.g. CLRF TMR0, MOVWF TMR0, BSF TMR0, x....etc.) will clear the prescaler count. Note: Writing to TMR0 when the prescaler is assigned to Timer0 will clear the prescaler count, but will not change the prescaler assignment.
TMR0H is not the high byte of the timer/counter in 16-bit mode, but is actually a buffered version of the high byte of Timer0 (refer to Figure 9-2). The high byte of the Timer0 counter/timer is not directly readable nor writable. TMR0H is updated with the contents of the high byte of Timer0 during a read of TMR0L. This provides the ability to read all 16-bits of Timer0 without having to verify that the read of the high and low byte were valid due to a rollover between successive reads of the high and low byte. A write to the high byte of Timer0 must also take place through the TMR0H buffer register. Timer0 high byte is updated with the contents of TMR0H when a write occurs to TMR0L. This allows all 16-bits of Timer0 to be updated at once.
TABLE 9-1:
Name TMR0L TMR0H INTCON T0CON TRISA
REGISTERS ASSOCIATED WITH TIMER0
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on POR, BOR
xxxx xxxx 0000 0000
Value on all other RESETS
uuuu uuuu 0000 0000 0000 000u 1111 1111 --11 1111
Timer0 Module's Low Byte Register Timer0 Module's High Byte Register GIE/GIEH TMR0ON -- PEIE/GIEL T08BIT -- TMR0IE T0CS INT0IE T0SE RBIE PSA TMR0IF T0PS2 INT0IF T0PS1 RBIF T0PS0
0000 000x 1111 1111 --11 1111
PORTA Data Direction Register
Legend: x = unknown, u = unchanged, - = unimplemented locations read as '0'. Shaded cells are not used by Timer0.
2001 Microchip Technology Inc.
DS39206C-page 95
PIC18CXX2
NOTES:
DS39206C-page 96
2001 Microchip Technology Inc.
PIC18CXX2
10.0 TIMER1 MODULE
Figure 10-1 is a simplified block diagram of the Timer1 module. Register 10-1 details the Timer1 control register. This register controls the operating mode of the Timer1 module, and contains the Timer1 oscillator enable bit (T1OSCEN). Timer1 can be enabled or disabled by setting or clearing control bit TMR1ON (T1CON<0>). The Timer1 module timer/counter has the following features: * 16-bit timer/counter (two 8-bit registers: TMR1H and TMR1L) * Readable and writable (both registers) * Internal or external clock select * Interrupt-on-overflow from FFFFh to 0000h * Reset from CCP module special event trigger
REGISTER 10-1:
T1CON: TIMER1 CONTROL REGISTER
R/W-0 RD16 bit 7 U-0 -- R/W-0 T1CKPS1 R/W-0 T1CKPS0 R/W-0 T1OSCEN R/W-0 T1SYNC R/W-0 TMR1CS R/W-0 TMR1ON bit 0
bit 7
RD16: 16-bit Read/Write Mode Enable bit 1 = Enables register Read/Write of TImer1 in one 16-bit operation 0 = Enables register Read/Write of Timer1 in two 8-bit operations Unimplemented: Read as '0' T1CKPS1:T1CKPS0: Timer1 Input Clock Prescale Select bits 11 = 1:8 Prescale value 10 = 1:4 Prescale value 01 = 1:2 Prescale value 00 = 1:1 Prescale value T1OSCEN: Timer1 Oscillator Enable bit 1 = Timer1 Oscillator is enabled 0 = Timer1 Oscillator is shut-off The oscillator inverter and feedback resistor are turned off to eliminate power drain. T1SYNC: Timer1 External Clock Input Synchronization Select bit When TMR1CS = 1: 1 = Do not synchronize external clock input 0 = Synchronize external clock input When TMR1CS = 0: This bit is ignored. Timer1 uses the internal clock when TMR1CS = 0. TMR1CS: Timer1 Clock Source Select bit 1 = External clock from pin RC0/T1OSO/T13CKI (on the rising edge) 0 = Internal clock (FOSC/4) TMR1ON: Timer1 On bit 1 = Enables Timer1 0 = Stops Timer1 Legend: R = Readable bit - n = Value at POR reset W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown
bit 6 bit 5-4
bit 3
bit 2
bit 1
bit 0
2001 Microchip Technology Inc.
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PIC18CXX2
10.1 Timer1 Operation
Timer1 can operate in one of these modes: * As a timer * As a synchronous counter * As an asynchronous counter The operating mode is determined by the clock select bit, TMR1CS (T1CON<1>). When TMR1CS = 0, Timer1 increments every instruction cycle. When TMR1CS = 1, Timer1 increments on every rising edge of the external clock input or the Timer1 oscillator, if enabled. When the Timer1 oscillator is enabled (T1OSCEN is set), the RC1/T1OSI and RC0/T1OSO/T1CKI pins become inputs. That is, the TRISC<1:0> value is ignored. Timer1 also has an internal "RESET input". This RESET can be generated by the CCP module (Section 13.0).
FIGURE 10-1:
TMR1IF Overflow Interrupt Flag bit
TIMER1 BLOCK DIAGRAM
CCP Special Event Trigger TMR1 TMR1H CLR TMR1L TMR1ON On/Off T1OSC 0 1 T1SYNC Prescaler 1, 2, 4, 8 0 2 T1CKPS1:T1CKPS0 TMR1CS SLEEP Input Synchronize det Synchronized Clock Input
T1CKI/T1OSO T1OSI
T1OSCEN Enable Oscillator(1)
1 FOSC/4 Internal Clock
Note 1: When enable bit T1OSCEN is cleared, the inverter and feedback resistor are turned off. This eliminates power drain.
FIGURE 10-2:
TIMER1 BLOCK DIAGRAM: 16-BIT READ/WRITE MODE
Data Bus<7:0> 8 TMR1H 8 Write TMR1L Read TMR1L 8
CCP Special Event Trigger
TMR1IF Overflow Interrupt Flag bit
8
TMR1 Timer 1 High Byte CLR TMR1L
0 1 TMR1ON On/Off 1 T1SYNC
Synchronized Clock Input
T1OSC T13CKI/T1OSO T1OSCEN Enable Oscillator(1)
T1OSI
FOSC/4 Internal Clock
Prescaler 1, 2, 4, 8 0 2 TMR1CS T1CKPS1:T1CKPS0
Synchronize det
SLEEP Input
Note 1: When enable bit T1OSCEN is cleared, the inverter and feedback resistor are turned off. This eliminates power drain.
DS39206C-page 98
2001 Microchip Technology Inc.
PIC18CXX2
10.2 Timer1 Oscillator 10.4
A crystal oscillator circuit is built-in between pins T1OSI (input) and T1OSO (amplifier output). It is enabled by setting control bit T1OSCEN (T1CON<3>). The oscillator is a low power oscillator rated up to 200 kHz. It will continue to run during SLEEP. It is primarily intended for a 32 kHz crystal. Table 10-1 shows the capacitor selection for the Timer1 oscillator. The user must provide a software time delay to ensure proper start-up of the Timer1 oscillator.
Resetting Timer1 using a CCP Trigger Output
If the CCP module is configured in compare mode to generate a "special event trigger" (CCP1M3:CCP1M0 = 1011), this signal will reset Timer1 and start an A/D conversion (if the A/D module is enabled). Note: The special event triggers from the CCP1 module will not set interrupt flag bit TMR1IF (PIR1<0>).
TABLE 10-1:
CAPACITOR SELECTION FOR THE ALTERNATE OSCILLATOR
Freq. 32 kHz C1 TBD(1) C2 TBD(1)
Timer1 must be configured for either timer or synchronized counter mode to take advantage of this feature. If Timer1 is running in asynchronous counter mode, this reset operation may not work. In the event that a write to Timer1 coincides with a special event trigger from CCP1, the write will take precedence. In this mode of operation, the CCPR1H:CCPR1L registers pair effectively becomes the period register for Timer1.
Osc Type LP
Crystal to be Tested: 32.768 kHz Epson C-001R32.768K-A 20 PPM
Note 1: Microchip suggests 33 pF as a starting point in validating the oscillator circuit. 2: Higher capacitance increases the stability of the oscillator, but also increases the start-up time. 3: Since each resonator/crystal has its own characteristics, the user should consult the resonator/crystal manufacturer for appropriate values of external components. 4: Capacitor values are for design guidance only.
10.5
Timer1 16-Bit Read/Write Mode
Timer1 can be configured for 16-bit reads and writes (see Figure 10-2). When the RD16 control bit (T1CON<7>) is set, the address for TMR1H is mapped to a buffer register for the high byte of Timer1. A read from TMR1L will load the contents of the high byte of Timer1 into the Timer1 high byte buffer. This provides the user with the ability to accurately read all 16-bits of Timer1, without having to determine whether a read of the high byte, followed by a read of the low byte, is valid, due to a rollover between reads. A write to the high byte of Timer1 must also take place through the TMR1H buffer register. Timer1 high byte is updated with the contents of TMR1H when a write occurs to TMR1L. This allows a user to write all 16 bits to both the high and low bytes of Timer1 at once. TMR1H is updated from the high byte when TMR1L is read. The high byte of Timer1 is not directly readable or writable in this mode. All reads and writes must take place through the Timer1 high byte buffer register. Writes to TMR1H do not clear the Timer1 prescaler. The prescaler is only cleared on writes to TMR1L.
10.3
Timer1 Interrupt
The TMR1 Register pair (TMR1H:TMR1L) increments from 0000h to FFFFh and rolls over to 0000h. The TMR1 Interrupt, if enabled, is generated on overflow, which is latched in interrupt flag bit TMR1IF (PIR1<0>). This interrupt can be enabled/disabled by setting/clearing TMR1 interrupt enable bit TMR1IE (PIE1<0>).
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TABLE 10-2:
Name INTCON PIR1 PIE1 IPR1 TMR1L TMR1H T1CON Bit 7 GIE/GIEH PSPIF(1) PSPIE(1) PSPIP(1)
REGISTERS ASSOCIATED WITH TIMER1 AS A TIMER/COUNTER
Bit 6 PEIE/ GIEL ADIF ADIE ADIP Bit 5 TMR0IE RCIF RCIE RCIP Bit 4 INT0IE TXIF TXIE TXIP Bit 3 RBIE SSPIF SSPIE SSPIP Bit 2 TMR0IF CCP1IF CCP1IE CCP1IP Bit 1 INT0IF TMR2IF TMR2IE TMR2IP Bit 0 RBIF TMR1IF TMR1IE TMR1IP Value on POR, BOR
0000 000x 0000 0000 0000 0000 0000 0000 xxxx xxxx xxxx xxxx
Value on all other RESETS
0000 000u 0000 0000 0000 0000 0000 0000 uuuu uuuu uuuu uuuu --uu uuuu
Holding Register for the Least Significant Byte of the 16-bit TMR1 Register Holding Register for the Most Significant Byte of the 16-bit TMR1 Register RD16 -- T1CKPS1 T1CKPS0 T1OSCEN T1SYNC TMR1CS TMR1ON
--00 0000
Legend: x = unknown, u = unchanged, - = unimplemented, read as '0'. Shaded cells are not used by the Timer1 module. Note 1: The PSPIF, PSPIE and PSPIP bits are reserved on the PIC18C2X2 devices. Always maintain these bits clear.
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PIC18CXX2
11.0
* * * * * * *
TIMER2 MODULE
11.1
Timer2 Operation
The Timer2 module timer has the following features: 8-bit timer (TMR2 register) 8-bit period register (PR2) Readable and writable (both registers) Software programmable prescaler (1:1, 1:4, 1:16) Software programmable postscaler (1:1 to 1:16) Interrupt on TMR2 match of PR2 SSP module optional use of TMR2 output to generate clock shift
Timer2 can be used as the PWM time-base for the PWM mode of the CCP module. The TMR2 register is readable and writable, and is cleared on any device RESET. The input clock (FOSC/4) has a prescale option of 1:1, 1:4, or 1:16, selected by control bits T2CKPS1:T2CKPS0 (T2CON<1:0>). The match output of TMR2 goes through a 4-bit postscaler (which gives a 1:1 to 1:16 scaling inclusive) to generate a TMR2 interrupt (latched in flag bit TMR2IF, (PIR1<1>)). The prescaler and postscaler counters are cleared when any of the following occurs: * a write to the TMR2 register * a write to the T2CON register * any device RESET (Power-on Reset, MCLR Reset, Watchdog Timer Reset, or Brown-out Reset) TMR2 is not cleared when T2CON is written.
Timer2 has a control register shown in Register 11-1. Timer2 can be shut-off by clearing control bit TMR2ON (T2CON<2>) to minimize power consumption. Figure 11-1 is a simplified block diagram of the Timer2 module. Register 11-1 shows the Timer2 control register. The prescaler and postscaler selection of Timer2 are controlled by this register.
REGISTER 11-1:
T2CON: TIMER2 CONTROL REGISTER
U-0 -- bit 7 R/W-0 R/W-0 R/W-0 TOUTPS1 R/W-0 TOUTPS0 R/W-0 TMR2ON R/W-0 T2CKPS1 R/W-0 T2CKPS0 bit 0 TOUTPS3 TOUTPS2
bit 7 bit 6-3
Unimplemented: Read as '0' TOUTPS3:TOUTPS0: Timer2 Output Postscale Select bits 0000 = 1:1 Postscale 0001 = 1:2 Postscale * * * 1111 = 1:16 Postscale TMR2ON: Timer2 On bit 1 = Timer2 is on 0 = Timer2 is off T2CKPS1:T2CKPS0: Timer2 Clock Prescale Select bits 00 = Prescaler is 1 01 = Prescaler is 4 1x = Prescaler is 16 Legend: R = Readable bit - n = Value at POR reset W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown
bit 2
bit 1-0
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11.2 Timer2 Interrupt 11.3 Output of TMR2
The Timer2 module has an 8-bit period register, PR2. Timer2 increments from 00h until it matches PR2 and then resets to 00h on the next increment cycle. PR2 is a readable and writable register. The PR2 register is initialized to FFh upon RESET. The output of TMR2 (before the postscaler) is fed to the Synchronous Serial Port module, which optionally uses it to generate the shift clock.
FIGURE 11-1:
TIMER2 BLOCK DIAGRAM
TMR2 Output(1) Sets Flag bit TMR2IF
FOSC/4
Prescaler 1:1, 1:4, 1:16 2 T2CKPS1:T2CKPS0
TMR2
RESET
Comparator EQ PR2
Postscaler 1:1 to 1:16 4 TOUTPS3:TOUTPS0
Note 1:
TMR2 register output can be software selected by the SSP Module as a baud clock.
TABLE 11-1:
Name Bit 7
REGISTERS ASSOCIATED WITH TIMER2 AS A TIMER/COUNTER
Bit 6 Bit 5 TMR0IE RCIF RCIE RCIP Bit 4 INT0IE TXIF TXIE TXIP Bit 3 RBIE SSPIF SSPIE SSPIP Bit 2 TMR0IF CCP1IF CCP1IE CCP1IP Bit 1 INT0IF TMR2IF TMR2IE TMR2IP Bit 0 RBIF TMR1IF TMR1IE TMR1IP Value on POR, BOR Value on all other RESETS
INTCON GIE/GIEH PEIE/GIEL PIR1 PIE1 IPR1 TMR2 T2CON PR2 PSPIF
(1)
0000 000x 0000 000u 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000
ADIF ADIE ADIP
PSPIE(1) PSPIP(1) --
Timer2 Module Register Timer2 Period Register
TOUTPS3 TOUTPS2 TOUTPS1 TOUTPS0 TMR2ON T2CKPS1 T2CKPS0 -000 0000 -000 0000
1111 1111 1111 1111
Legend: x = unknown, u = unchanged, - = unimplemented, read as '0'. Shaded cells are not used by the Timer2 module. Note 1: The PSPIF, PSPIE and PSPIP bits are reserved on the PIC18C2X2 devices. Always maintain these bits clear.
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PIC18CXX2
12.0 TIMER3 MODULE
Figure 12-1 is a simplified block diagram of the Timer3 module. Register 12-1 shows the Timer3 control register. This register controls the operating mode of the Timer3 module and sets the CCP clock source. Register 10-1 shows the Timer1 control register. This register controls the operating mode of the Timer1 module, as well as contains the Timer1 oscillator enable bit (T1OSCEN), which can be a clock source for Timer3. The Timer3 module timer/counter has the following features: * 16-bit timer/counter (two 8-bit registers: TMR3H and TMR3L) * Readable and writable (both registers) * Internal or external clock select * Interrupt-on-overflow from FFFFh to 0000h * Reset from CCP module trigger
REGISTER 12-1:
T3CON: TIMER3 CONTROL REGISTER
R/W-0 RD16 bit 7 R/W-0 T3CCP2 R/W-0 T3CKPS1 R/W-0 T3CKPS0 R/W-0 T3CCP1 R/W-0 T3SYNC R/W-0 TMR3CS R/W-0 TMR3ON bit 0
bit 7
RD16: 16-bit Read/Write Mode Enable 1 = Enables register Read/Write of Timer3 in one 16-bit operation 0 = Enables register Read/Write of Timer3 in two 8-bit operations T3CCP2:T3CCP1: Timer3 and Timer1 to CCPx Enable bits 1x = Timer3 is the clock source for compare/capture CCP modules 01 = Timer3 is the clock source for compare/capture of CCP2, Timer1 is the clock source for compare/capture of CCP1 00 = Timer1 is the clock source for compare/capture CCP modules T3CKPS1:T3CKPS0: Timer3 Input Clock Prescale Select bits 11 = 1:8 Prescale value 10 = 1:4 Prescale value 01 = 1:2 Prescale value 00 = 1:1 Prescale value T3SYNC: Timer3 External Clock Input Synchronization Control bit (Not usable if the system clock comes from Timer1/Timer3.) When TMR3CS = 1: 1 = Do not synchronize external clock input 0 = Synchronize external clock input When TMR3CS = 0: This bit is ignored. Timer3 uses the internal clock when TMR3CS = 0. TMR3CS: Timer3 Clock Source Select bit 1 = External clock input from Timer1 oscillator or T1CKI (on the rising edge after the first falling edge) 0 = Internal clock (FOSC/4) TMR3ON: Timer3 On bit 1 = Enables Timer3 0 = Stops Timer3 Legend: R = Readable bit - n = Value at POR reset W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown
bit 6-3
bit 5-4
bit 2
bit 1
bit 0
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12.1 Timer3 Operation
Timer3 can operate in one of these modes: * As a timer * As a synchronous counter * As an asynchronous counter The operating mode is determined by the clock select bit, TMR3CS (T3CON<1>). When TMR3CS = 0, Timer3 increments every instruction cycle. When TMR3CS = 1, Timer3 increments on every rising edge of the Timer1 external clock input or the Timer1 oscillator, if enabled. When the Timer1 oscillator is enabled (T1OSCEN is set), the RC1/T1OSI and RC0/T1OSO/T1CKI pins become inputs. That is, the TRISC<1:0> value is ignored. Timer3 also has an internal "RESET input". This RESET can be generated by the CCP module (Section 12.0).
FIGURE 12-1:
TIMER3 BLOCK DIAGRAM
TMR3IF Overflow Interrupt Flag bit TMR3H CCP Special Trigger T3CCPx CLR TMR3L 1 TMR3ON On/Off T3SYNC 0 Synchronized Clock Input
T1OSO/ T13CKI
T1OSC
(3)
1 T1OSCEN FOSC/4 Enable Internal Oscillator(1) Clock Prescaler 1, 2, 4, 8 0 2 TMR3CS T3CKPS1:T3CKPS0
Synchronize det
T1OSI
SLEEP Input
Note 1: When enable bit T1OSCEN is cleared, the inverter and feedback resistor are turned off. This eliminates power drain.
FIGURE 12-2:
TIMER3 BLOCK DIAGRAM CONFIGURED IN 16-BIT READ/WRITE MODE
8 TMR3H 8 8
Data Bus<7:0>
Write TMR3L Read TMR3L Set TMR3IF Flag bit on Overflow 8 Timer3 High Byte TMR3 TMR3L CLR 1 To Timer1 Clock Input T1OSO/ T13CKI T1OSC 1 T1OSCEN Enable Oscillator(1) FOSC/4 Internal Clock Prescaler 1, 2, 4, 8 0 2 T3CKPS1:T3CKPS0 TMR3CS SLEEP Input TMR3ON On/Off T3SYNC Synchronize det CCP Special Trigger T3CCPx 0 Synchronized Clock Input
T1OSI
Note 1: When enable bit T1OSCEN is cleared, the inverter and feedback resistor are turned off. This eliminates power drain.
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PIC18CXX2
12.2 Timer1 Oscillator 12.4
The Timer1 oscillator may be used as the clock source for Timer3. The Timer1 oscillator is enabled by setting the T1OSCEN (T1CON<3>) bit. The oscillator is a low power oscillator rated up to 200 KHz. See Section 10.0 for further details.
Resetting Timer3 Using a CCP Trigger Output
If the CCP module is configured in Compare mode to generate a "special event trigger" (CCP1M3:CCP1M0 = 1011), this signal will reset Timer3. Note: The special event triggers from the CCP module will not set interrupt flag bit TMR3IF (PIR1<0>).
12.3
Timer3 Interrupt
The TMR3 Register pair (TMR3H:TMR3L) increments from 0000h to FFFFh and rolls over to 0000h. The TMR3 interrupt, if enabled, is generated on overflow which is latched in interrupt flag bit TMR3IF (PIR2<1>). This interrupt can be enabled/disabled by setting/clearing TMR3 interrupt enable bit, TMR3IE (PIE2<1>).
Timer3 must be configured for either Timer or Synchronized Counter mode to take advantage of this feature. If Timer3 is running in Asynchronous Counter mode, this RESET operation may not work. In the event that a write to Timer3 coincides with a special event trigger from CCP1, the write will take precedence. In this mode of operation, the CCPR1H:CCPR1L registers pair effectively becomes the period register for Timer3.
TABLE 12-1:
Name Bit 7 GIE/ GIEH -- -- --
REGISTERS ASSOCIATED WITH TIMER3 AS A TIMER/COUNTER
Bit 6 PEIE/ GIEL -- -- -- Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on POR, BOR Value on all other RESETS
INTCON PIR2 PIE2 IPR2 TMR3L TMR3H T1CON T3CON Legend:
TMR0IE -- -- --
INT0IE -- -- --
RBIE BCLIF BCLIE BCLIP
TMR0IF LVDIF LVDIE LVDIP
INT0IF TMR3IF TMR3IE TMR3IP
RBIF CCP2IF CCP2IE CCP2IP
0000 000x 0000 000u 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 xxxx xxxx uuuu uuuu xxxx xxxx uuuu uuuu
Holding Register for the Least Significant Byte of the 16-bit TMR3 Register Holding Register for the Most Significant Byte of the 16-bit TMR3 Register RD16 RD16 -- T3CCP2 T1CKPS1 T1CKPS0 T1OSCEN T3CKPS1 T3CKPS0 T3CCP1 T1SYNC T3SYNC
TMR1CS TMR1ON --00 0000 --uu uuuu TMR3CS TMR3ON -000 0000 -uuu uuuu
x = unknown, u = unchanged, - = unimplemented, read as '0'. Shaded cells are not used by the Timer1 module.
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NOTES:
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PIC18CXX2
13.0 CAPTURE/COMPARE/PWM (CCP) MODULES
The operation of CCP1 is identical to that of CCP2, with the exception of the special event trigger. Therefore, operation of a CCP module in the following sections is described with respect to CCP1. Table 13-2 shows the interaction of the CCP modules.
Each CCP (Capture/Compare/PWM) module contains a 16-bit register which can operate as a 16-bit capture register, as a 16-bit compare register, or as a PWM master/slave Duty Cycle register. Table 13-1 shows the timer resources of the CCP module modes.
REGISTER 13-1:
CCP1CON REGISTER/CCP2CON REGISTER
U-0 -- bit 7 U-0 -- R/W-0 DCxB1 R/W-0 DCxB0 R/W-0 CCPxM3 R/W-0 CCPxM2 R/W-0 CCPxM1 R/W-0 CCPxM0 bit 0
bit 7-6 bit 5-4
Unimplemented: Read as '0' DCxB1:DCxB0: PWM Duty Cycle bit1 and bit0 Capture mode: Unused Compare mode: Unused PWM mode: These bits are the two LSbs (bit1 and bit0) of the 10-bit PWM duty cycle. The upper eight bits (DCx9:DCx2) of the duty cycle are found in CCPRxL. CCPxM3:CCPxM0: CCPx Mode Select bits 0000 = Capture/Compare/PWM off (resets CCPx module) 0001 = Reserved 0010 = Compare mode, toggle output on match (CCPxIF bit is set) 0011 = Reserved 0100 = Capture mode, every falling edge 0101 = Capture mode, every rising edge 0110 = Capture mode, every 4th rising edge 0111 = Capture mode, every 16th rising edge 1000 = Compare mode, Initialize CCP pin Low, on compare match force CCP pin High (CCPIF bit is set) 1001 = Compare mode, Initialize CCP pin High, on compare match force CCP pin Low (CCPIF bit is set) 1010 = Compare mode, Generate software interrupt on compare match (CCPIF bit is set, CCP pin is unaffected) 1011 = Compare mode, Trigger special event (CCPIF bit is set) 11xx = PWM mode Legend: R = Readable bit - n = Value at POR reset W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown
bit 3-0
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13.1 CCP1 Module 13.2 CCP2 Module
Capture/Compare/PWM Register 1 (CCPR1) is comprised of two 8-bit registers: CCPR1L (low byte) and CCPR1H (high byte). The CCP1CON register controls the operation of CCP1. All are readable and writable. Capture/Compare/PWM Register2 (CCPR2) is comprised of two 8-bit registers: CCPR2L (low byte) and CCPR2H (high byte). The CCP2CON register controls the operation of CCP2. All are readable and writable.
TABLE 13-1:
CCP MODE - TIMER RESOURCE
Timer Resource Timer1 or Timer3 Timer1 or Timer3 Timer2
CCP Mode Capture Compare PWM
TABLE 13-2:
INTERACTION OF TWO CCP MODULES
Interaction TMR1 or TMR3 time-base. Time-base can be different for each CCP. The compare could be configured for the special event trigger, which clears either TMR1, or TMR3, depending upon which time-base is used. The compare(s) could be configured for the special event trigger, which clears TMR1, or TMR3, depending upon which time-base is used. The PWMs will have the same frequency and update rate (TMR2 interrupt). None. None.
CCPx Mode CCPy Mode Capture Capture Compare PWM PWM PWM Capture Compare Compare PWM Capture Compare
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PIC18CXX2
13.3 Capture Mode
13.3.3 SOFTWARE INTERRUPT
In Capture mode, CCPR1H:CCPR1L captures the 16-bit value of the TMR1 or TMR3 registers when an event occurs on pin RC2/CCP1. An event is defined as: * * * * every falling edge every rising edge every 4th rising edge every 16th rising edge When the Capture mode is changed, a false capture interrupt may be generated. The user should keep bit CCP1IE (PIE1<2>) clear to avoid false interrupts and should clear the flag bit, CCP1IF, following any such change in operating mode.
13.3.4
CCP PRESCALER
An event is selected by control bits CCP1M3:CCP1M0 (CCP1CON<3:0>). When a capture is made, the interrupt request flag bit CCP1IF (PIR1<2>) is set. It must be cleared in software. If another capture occurs before the value in register CCPR1 is read, the old captured value will be lost.
There are four prescaler settings, specified by bits CCP1M3:CCP1M0. Whenever the CCP module is turned off, or the CCP module is not in Capture mode, the prescaler counter is cleared. This means that any RESET will clear the prescaler counter. Switching from one capture prescaler to another may generate an interrupt. Also, the prescaler counter will not be cleared, therefore, the first capture may be from a non-zero prescaler. Example 13-1 shows the recommended method for switching between capture prescalers. This example also clears the prescaler counter and will not generate the "false" interrupt.
13.3.1
CCP PIN CONFIGURATION
In Capture mode, the RC2/CCP1 pin should be configured as an input by setting the TRISC<2> bit. Note: If the RC2/CCP1 is configured as an output, a write to the port can cause a capture condition.
EXAMPLE 13-1:
CLRF MOVLW
CHANGING BETWEEN CAPTURE PRESCALERS
13.3.2
TIMER1/TIMER3 MODE SELECTION
The timers that are to be used with the capture feature (either Timer1 and/or Timer3) must be running in Timer mode or Synchronized Counter mode. In Asynchronous Counter mode, the capture operation may not work. The timer to be used with each CCP module is selected in the T3CON register.
MOVWF
CCP1CON, F ; Turn CCP module off NEW_CAPT_PS ; Load WREG with the ; new prescaler mode ; value and CCP ON CCP1CON ; Load CCP1CON with ; this value
FIGURE 13-1:
CAPTURE MODE OPERATION BLOCK DIAGRAM
TMR3H Set Flag bit CCP1IF Prescaler / 1, 4, 16 T3CCP2 TMR3 Enable CCPR1H and Edge Detect TMR1 Enable TMR1H CCP1CON<3:0> Q's Set Flag bit CCP2IF T3CCP1 T3CCP2 Prescaler / 1, 4, 16 TMR3H TMR3 Enable CCPR2H and Edge Detect TMR1 Enable T3CCP2 T3CCP1 TMR1H TMR1L CCPR2L TMR3L TMR1L CCPR1L TMR3L
CCP1 pin
T3CCP2
CCP2 pin
CCP2CON<3:0> Q's
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13.4 Compare Mode
13.4.2 TIMER1/TIMER3 MODE SELECTION
In Compare mode, the 16-bit CCPR1 (CCPR2) register value is constantly compared against either the TMR1 register pair value or the TMR3 register pair value. When a match occurs, the RC2/CCP1 (RC1/CCP2) pin is: * * * * driven High driven Low toggle output (High to Low or Low to High) remains unchanged Timer1 and/or Timer3 must be running in Timer mode, or Synchronized Counter mode, if the CCP module is using the compare feature. In Asynchronous Counter mode, the compare operation may not work.
13.4.3
SOFTWARE INTERRUPT MODE
When generate software interrupt is chosen, the CCP1 pin is not affected. Only a CCP interrupt is generated (if enabled).
The action on the pin is based on the value of control bits CCP1M3:CCP1M0 (CCP2M3:CCP2M0). At the same time, interrupt flag bit, CCP1IF (CCP2IF) is set.
13.4.4
SPECIAL EVENT TRIGGER
In this mode, an internal hardware trigger is generated, which may be used to initiate an action. The special event trigger output of CCP1 resets the TMR1 register pair. This allows the CCPR1 register to effectively be a 16-bit programmable period register for Timer1. The special trigger output of CCPx resets either the TMR1 or TMR3 register pair. Additionally, the CCP2 Special Event Trigger will start an A/D conversion if the A/D module is enabled. Note: The special event trigger from the CCP2 module will not set the Timer1 or Timer3 interrupt flag bits.
13.4.1
CCP PIN CONFIGURATION
The user must configure the CCPx pin as an output by clearing the appropriate TRISC bit. Note: Clearing the CCP1CON register will force the RC2/CCP1 compare output latch to the default low level. This is not the data latch.
FIGURE 13-2:
COMPARE MODE OPERATION BLOCK DIAGRAM
Special Event Trigger will: Reset Timer1or Timer3, but not set Timer1 or Timer3 Interrupt Flag bit, and set bit GO/DONE (ADCON0<2>) which starts an A/D Conversion (CCP2 only) Special Event Trigger
Set Flag bit CCP1IF CCPR1H CCPR1L Q RC2/CCP1 pin TRISC<2> Output Enable S R Output Logic Comparator
Match
CCP1CON<3:0> Mode Select
T3CCP2
0
1
TMR1H Special Event Trigger
TMR1L
TMR3H
TMR3L
Set Flag bit CCP2IF
T3CCP1 T3CCP2
0
1
Q RC1/CCP2 pin TRISC<1> Output Enable
S R
Output Logic
Match
Comparator CCPR2H CCPR2L
CCP2CON<3:0> Mode Select
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PIC18CXX2
TABLE 13-3:
Name
REGISTERS ASSOCIATED WITH CAPTURE, COMPARE, TIMER1 AND TIMER3
Bit 6 PEIE/ GIEL ADIF ADIE ADIP Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on POR, BOR Value on all other RESETS
Bit 7
INTCON PIR1 PIE1 IPR1 TRISC TMR1L TMR1H T1CON CCPR1L CCPR1H CCP1CON CCPR2L CCPR2H CCP2CON PIR2 PIE2 IPR2 TMR3L TMR3H T3CON
GIE/GIEH PSPIF(1) PSPIE(1) PSPIP(1)
TMR0IE RCIF RCIE RCIP
INT0IE TXIF TXIE TXIP
RBIE SSPIF SSPIE SSPIP
TMR0IF CCP1IF CCP1IE CCP1IP
INT0IF TMR2IF TMR2IE TMR2IP
RBIF TMR1IF TMR1IE TMR1IP
0000 000x 0000 000u 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 1111 1111 1111 1111 xxxx xxxx uuuu uuuu xxxx xxxx uuuu uuuu xxxx xxxx uuuu uuuu xxxx xxxx uuuu uuuu
PORTC Data Direction Register Holding Register for the Least Significant Byte of the 16-bit TMR1 Register Holding Register for the Most Significant Byte of the 16-bit TMR1 Register RD16 -- Capture/Compare/PWM Register1 (LSB) Capture/Compare/PWM Register1 (MSB) -- -- DC1B1 DC1B0 CCP1M3 Capture/Compare/PWM Register2 (LSB) Capture/Compare/PWM Register2 (MSB) -- -- -- -- -- -- -- -- DC2B1 -- -- -- DC2B0 -- -- -- CCP2M3 BCLIF BCLIE BCLIP LVDIF LVDIE LVDIP TMR3IF TMR3IE TMR3IP CCP2IF CCP2IE CCP2IP
T1CKPS1 T1CKPS0 T1OSCEN T1SYNC TMR1CS TMR1ON --00 0000 --uu uuuu
CCP1M2 CCP1M1 CCP1M0 --00 0000 --00 0000
xxxx xxxx uuuu uuuu xxxx xxxx uuuu uuuu
CCP2M2 CCP2M1 CCP2M0 --00 0000 --00 0000
0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 xxxx xxxx uuuu uuuu xxxx xxxx uuuu uuuu
Holding Register for the Least Significant Byte of the 16-bit TMR3 Register Holding Register for the Most Significant Byte of the 16-bit TMR3 Register RD16 T3CCP2 T3CKPS1 T3CKPS0 T3CCP1
T3SYNC TMR3CS TMR3ON -000 0000 -uuu uuuu
Legend: x = unknown, u = unchanged, - = unimplemented, read as '0'. Shaded cells are not used by Capture and Timer1. Note 1: The PSPIF, PSPIE and PSPIP bits are reserved on the PIC18C2X2 devices. Always maintain these bits clear.
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13.5 PWM Mode
13.5.1 PWM PERIOD
In Pulse Width Modulation (PWM) mode, the CCP1 pin produces up to a 10-bit resolution PWM output. Since the CCP1 pin is multiplexed with the PORTC data latch, the TRISC<2> bit must be cleared to make the CCP1 pin an output. Note: Clearing the CCP1CON register will force the CCP1 PWM output latch to the default low level. This is not the PORTC I/O data latch. The PWM period is specified by writing to the PR2 register. The PWM period can be calculated using the following formula: PWM period = (PR2) + 1] * 4 * TOSC * (TMR2 prescale value) PWM frequency is defined as 1 / [PWM period]. When TMR2 is equal to PR2, the following three events occur on the next increment cycle: * TMR2 is cleared * The CCP1 pin is set (exception: if PWM duty cycle = 0%, the CCP1 pin will not be set) * The PWM duty cycle is latched from CCPR1L into CCPR1H Note: The Timer2 postscaler (see Section 11.0) is not used in the determination of the PWM frequency. The postscaler could be used to have a servo update rate at a different frequency than the PWM output.
Figure 13-3 shows a simplified block diagram of the CCP module in PWM mode. For a step-by-step procedure on how to set up the CCP module for PWM operation, see Section 13.5.3.
FIGURE 13-3:
SIMPLIFIED PWM BLOCK DIAGRAM
CCP1CON<5:4>
Duty Cycle Registers CCPR1L
13.5.2
PWM DUTY CYCLE
CCPR1H (Slave)
Comparator
R
Q RC2/CCP1
TMR2
(Note 1) S TRISC<2> Clear Timer, CCP1 pin and latch D.C.
The PWM duty cycle is specified by writing to the CCPR1L register and to the CCP1CON<5:4> bits. Up to 10-bit resolution is available. The CCPR1L contains the eight MSbs and the CCP1CON<5:4> contains the two LSbs. This 10-bit value is represented by CCPR1L:CCP1CON<5:4>. The following equation is used to calculate the PWM duty cycle in time: PWM duty cycle = (CCPR1L:CCP1CON<5:4>) * TOSC * (TMR2 prescale value) CCPR1L and CCP1CON<5:4> can be written to at any time, but the duty cycle value is not latched into CCPR1H until after a match between PR2 and TMR2 occurs (i.e., the period is complete). In PWM mode, CCPR1H is a read only register. The CCPR1H register and a 2-bit internal latch are used to double buffer the PWM duty cycle. This double buffering is essential for glitchless PWM operation. When the CCPR1H and 2-bit latch match TMR2 concatenated with an internal 2-bit Q clock or 2 bits of the TMR2 prescaler, the CCP1 pin is cleared. The maximum PWM resolution (bits) for a given PWM frequency is given by the equation: FOSC log --------------- FPWM PWM Resolution (max) = -----------------------------bits log ( 2 )
Comparator
PR2 Note:
8-bit timer is concatenated with 2-bit internal Q clock or 2 bits of the prescaler to create 10-bit time-base.
A PWM output (Figure 13-4) has a time-base (period) and a time that the output stays high (duty cycle). The frequency of the PWM is the inverse of the period (1/period).
FIGURE 13-4:
Period
PWM OUTPUT
Duty Cycle TMR2 = PR2 TMR2 = Duty Cycle TMR2 = PR2
Note:
If the PWM duty cycle value is longer than the PWM period, the CCP1 pin will not be cleared.
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PIC18CXX2
13.5.3 SETUP FOR PWM OPERATION
3. 4. 5. The following steps should be taken when configuring the CCP module for PWM operation: 1. 2. Set the PWM period by writing to the PR2 register. Set the PWM duty cycle by writing to the CCPR1L register and CCP1CON<5:4> bits. Make the CCP1 pin an output by clearing the TRISC<2> bit. Set the TMR2 prescale value and enable Timer2 by writing to T2CON. Configure the CCP1 module for PWM operation.
TABLE 13-4:
EXAMPLE PWM FREQUENCIES AND RESOLUTIONS AT 40 MHz
2.44 kHz 16 0xFF 14 9.77 kHz 4 0xFF 12 39.06 kHz 1 0xFF 10 156.25 kHz 1 0x3F 8 312.50 kHz 1 0x1F 7 416.67 kHz 1 0x17 6.58
PWM Frequency Timer Prescaler (1, 4, 16) PR2 Value Maximum Resolution (bits)
TABLE 13-5:
Name INTCON PIR1 PIE1 IPR1 TRISC TMR2 PR2 T2CON CCPR1L CCPR1H CCP1CON CCPR2L CCPR2H CCP2CON
REGISTERS ASSOCIATED WITH PWM AND TIMER2
Bit 6 PEIE/ GIEL ADIF ADIE ADIP Bit 5 TMR0IE RCIF RCIE RCIP Bit 4 INT0IE TXIF TXIE TXIP Bit 3 RBIE SSPIF SSPIE SSPIP Bit 2 TMR0IF CCP1IF CCP1IE CCP1IP Bit 1 INT0IF TMR2IF TMR2IE TMR2IP Bit 0 RBIF TMR1IF TMR1IE TMR1IP Value on POR, BOR Value on all other RESETS
Bit 7 GIE/ GIEH PSPIF(1) PSPIE(1) PSPIP(1)
0000 000x 0000 000u 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 1111 1111 1111 1111 0000 0000 0000 0000 1111 1111 1111 1111 xxxx xxxx uuuu uuuu xxxx xxxx uuuu uuuu
PORTC Data Direction Register Timer2 Module Register Timer2 Module Period Register -- Capture/Compare/PWM Register1 (LSB) Capture/Compare/PWM Register1 (MSB) -- -- DC1B1 DC1B0 CCP1M3 CCP1M2 CCP1M1 Capture/Compare/PWM Register2 (LSB) Capture/Compare/PWM Register2 (MSB) -- -- DC2B1 DC2B0 CCP2M3 CCP2M2 CCP2M1
TOUTPS3 TOUTPS2 TOUTPS1 TOUTPS0 TMR2ON T2CKPS1 T2CKPS0 -000 0000 -000 0000
CCP1M0 --00 0000 --00 0000
xxxx xxxx uuuu uuuu xxxx xxxx uuuu uuuu
CCP2M0 --00 0000 --00 0000
Legend: x = unknown, u = unchanged, - = unimplemented, read as '0'. Shaded cells are not used by PWM and Timer2. Note 1: The PSPIF, PSPIE and PSPIP bits are reserved on the PIC18C2X2 devices. Always maintain these bits clear.
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NOTES:
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PIC18CXX2
14.0 MASTER SYNCHRONOUS SERIAL PORT (MSSP) MODULE
Master SSP (MSSP) Module Overview
14.1
The Master Synchronous Serial Port (MSSP) module is a serial interface useful for communicating with other peripheral or microcontroller devices. These peripheral devices may be Serial EEPROMs, shift registers, display drivers, A/D converters, etc. The MSSP module can operate in one of two modes: * Serial Peripheral Interface (SPITM) * Inter-Integrated Circuit (I2CTM) - Full Master mode - Slave mode (with general address call) The I2C interface supports the following modes in hardware: * Master mode * Multi-Master mode * Slave mode
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14.2 Control Registers
The MSSP module has three associated registers. These include a status register (SSPSTAT) and two control registers (SSPCON1 and SSPCON2).
REGISTER 14-1:
SSPSTAT: MSSP STATUS REGISTER
R/W-0 SMP bit 7 R/W-0 CKE R-0 D/A R-0 P R-0 S R-0 R/W R-0 UA R-0 BF bit 0
bit 7
SMP: Sample bit SPI Master mode: 1 = Input data sampled at end of data output time 0 = Input data sampled at middle of data output time SPI Slave mode: SMP must be cleared when SPI is used in Slave mode In I2 C Master or Slave mode: 1 = Slew rate control disabled for standard speed mode (100 kHz and 1 MHz) 0 = Slew rate control enabled for high speed mode (400 kHz) CKE: SPI Clock Edge Select bit CKP = 0: 1 = Data transmitted on rising edge of SCK 0 = Data transmitted on falling edge of SCK CKP = 1: 1 = Data transmitted on falling edge of SCK 0 = Data transmitted on rising edge of SCK D/A: Data/Address bit (I2C mode only) 1 = Indicates that the last byte received or transmitted was data 0 = Indicates that the last byte received or transmitted was address P: STOP bit (I2C mode only. This bit is cleared when the MSSP module is disabled, SSPEN is cleared.) 1 = Indicates that a STOP bit has been detected last (this bit is '0' on RESET) 0 = STOP bit was not detected last Legend: R = Readable bit - n = Value at POR W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown
bit 6
bit 5
bit 4
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REGISTER 14-1: SSPSTAT: MSSP STATUS REGISTER (CONTINUED)
R/W-0 SMP bit 7 bit 3 R/W-0 CKE R-0 D/A R-0 P R-0 S R-0 R/W R-0 UA R-0 BF bit 0
S: START bit (I2C mode only. This bit is cleared when the MSSP module is disabled, SSPEN is cleared.) 1 = Indicates that a START bit has been detected last (this bit is '0' on RESET) 0 = START bit was not detected last R/W: Read/Write bit information (I2C mode only) This bit holds the R/W bit information following the last address match. This bit is only valid from the address match to the next START bit, STOP bit, or not ACK bit. In I2 C Slave mode: 1 = Read 0 = Write In I2 C Master mode: 1 = Transmit is in progress 0 = Transmit is not in progress OR-ing this bit with SEN, RSEN, PEN, RCEN, or ACKEN will indicate if the MSSP is in IDLE mode. UA: Update Address bit (10-bit I2C mode only) 1 = Indicates that the user needs to update the address in the SSPADD register 0 = Address does not need to be updated BF: Buffer Full Status bit Receive (SPI and I2 C modes): 1 = Receive complete, SSPBUF is full 0 = Receive not complete, SSPBUF is empty Transmit (I2 C mode only): 1 = Data transmit in progress (does not include the ACK and STOP bits), SSPBUF is full 0 = Data transmit complete (does not include the ACK and STOP bits), SSPBUF is empty Legend: R = Readable bit - n = Value at POR W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown
bit 2
bit 1
bit 0
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REGISTER 14-2: SSPCON1: MSSP CONTROL REGISTER1
R/W-0 WCOL bit 7 bit 7 R/W-0 SSPOV R/W-0 SSPEN R/W-0 CKP R/W-0 SSPM3 R/W-0 SSPM2 R/W-0 SSPM1 R/W-0 SSPM0 bit 0
WCOL: Write Collision Detect bit Master mode: 1 = A write to the SSPBUF register was attempted while the I2C conditions were not valid for a transmission to be started 0 = No collision Slave mode: 1 = The SSPBUF register is written while it is still transmitting the previous word (must be cleared in software) 0 = No collision SSPOV: Receive Overflow Indicator bit In SPI mode: 1 = A new byte is received while the SSPBUF register is still holding the previous data. In case of overflow, the data in SSPSR is lost. Overflow can only occur in Slave mode. In Slave mode, the user must read the SSPBUF, even if only transmitting data to avoid setting overflow. In Master mode, the overflow bit is not set, since each new reception (and transmission) is initiated by writing to the SSPBUF register (must be cleared in software). 0 = No overflow In I2 C mode: 1 = A byte is received while the SSPBUF register is still holding the previous byte. SSPOV is a "don't care" in Transmit mode (must be cleared in software). 0 = No overflow SSPEN: Synchronous Serial Port Enable bit In both modes when enabled, these pins must be properly configured as input or output. In SPI mode: 1 = Enables serial port and configures SCK, SDO, SDI, and SS as the source of the serial port pins 0 = Disables serial port and configures these pins as I/O port pins In I2 C mode: 1 = Enables the serial port and configures the SDA and SCL pins as the source of the serial port pins 0 = Disables serial port and configures these pins as I/O port pins Legend: R = Readable bit - n = Value at POR W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown
bit 6
bit 5
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PIC18CXX2
REGISTER 14-2: SSPCON1: MSSP CONTROL REGISTER1 (CONTINUED)
R/W-0 WCOL bit 7 bit 4 CKP: Clock Polarity Select bit In SPI mode: 1 = Idle state for clock is a high level 0 = Idle state for clock is a low level In I2 C Slave mode: SCK release control 1 = Enable clock 0 = Holds clock low (clock stretch). (Used to ensure data setup time.) In I2 C Master mode: Unused in this mode SSPM3:SSPM0: Synchronous Serial Port Mode Select bits 0000 = SPI Master mode, clock = FOSC/4 0001 = SPI Master mode, clock = FOSC/16 0010 = SPI Master mode, clock = FOSC/64 0011 = SPI Master mode, clock = TMR2 output/2 0100 = SPI Slave mode, clock = SCK pin. SS pin control enabled. 0101 = SPI Slave mode, clock = SCK pin. SS pin control disabled. SS can be used as I/O pin. 0110 = I2C Slave mode, 7-bit address 0111 = I2C Slave mode, 10-bit address 1000 = I2C Master mode, clock = FOSC / (4 * (SSPADD+1)) 1001 = Reserved 1010 = Reserved 1011 = I2C firmware controlled Master mode (Slave idle) 1100 = Reserved 1101 = Reserved 1110 = I2C Slave mode, 7-bit address with START and STOP bit interrupts enabled 1111 = I2C Slave mode, 10-bit address with START and STOP bit interrupts enabled Legend: R = Readable bit - n = Value at POR W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown R/W-0 SSPOV R/W-0 SSPEN R/W-0 CKP R/W-0 SSPM3 R/W-0 SSPM2 R/W-0 SSPM1 R/W-0 SSPM0 bit 0
bit 3-0
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REGISTER 14-3: SSPCON2: MSSP CONTROL REGISTER2
R/W-0 GCEN bit 7 bit 7 GCEN: General Call Enable bit (In I2C Slave mode only) 1 = Enable interrupt when a general call address (0000h) is received in the SSPSR 0 = General call address disabled ACKSTAT: Acknowledge Status bit (In I2C Master mode only) In Master Transmit mode: 1 = Acknowledge was not received from slave 0 = Acknowledge was received from slave ACKDT: Acknowledge Data bit (In I2C Master mode only) In Master Receive mode: Value that will be transmitted when the user initiates an Acknowledge sequence at the end of a receive. 1 = Not Acknowledge 0 = Acknowledge ACKEN: Acknowledge Sequence Enable bit (In I2C Master mode only) In Master Receive mode: 1 = Initiate Acknowledge sequence on SDA and SCL pins, and transmit ACKDT data bit. Automatically cleared by hardware. 0 = Acknowledge sequence idle RCEN: Receive Enable bit (In I2C Master mode only) 1 = Enables Receive mode for I2C 0 = Receive idle PEN: STOP Condition Enable bit (In I2C Master mode only) SCK Release Control: 1 = Initiate STOP condition on SDA and SCL pins. Automatically cleared by hardware. 0 = STOP condition idle RSEN: Repeated START Condition Enabled bit (In I2C Master mode only) 1 = Initiate Repeated START condition on SDA and SCL pins. Automatically cleared by hardware. 0 = Repeated START condition idle SEN: START Condition Enabled bit (In I2C Master mode only) 1 = Initiate START condition on SDA and SCL pins. Automatically cleared by hardware. 0 = START condition idle Note: For bits ACKEN, RCEN, PEN, RSEN, SEN: If the I2C module is not in the Idle mode, this bit may not be set (no spooling) and the SSPBUF may not be written (or writes to the SSPBUF are disabled). R/W-0 ACKSTAT R/W-0 ACKDT R/W-0 ACKEN R/W-0 RCEN R/W-0 PEN R/W-0 RSEN R/W-0 SEN bit 0
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
Legend: R = Readable bit - n = Value at POR reset W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown
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PIC18CXX2
14.3 SPI Mode
FIGURE 14-1:
The SPI mode allows 8-bits of data to be synchronously transmitted and received simultaneously. All four modes of SPI are supported. To accomplish communication, typically three pins are used: * Serial Data Out (SDO) - RC5/SDO * Serial Data In (SDI) - RC4/SDI/SDA * Serial Clock (SCK) - RC3/SCK/SCL/LVOIN Additionally, a fourth pin may be used when in a Slave mode of operation: * Slave Select (SS) - RA5/SS/AN4
SDI SDO bit0
MSSP BLOCK DIAGRAM (SPI MODE)
Internal Data Bus
Read SSPBUF reg
Write
SSPSR reg Shift Clock
14.3.1
OPERATION
When initializing the SPI, several options need to be specified. This is done by programming the appropriate control bits (SSPCON1<5:0>) and SSPSTAT<7:6>. These control bits allow the following to be specified: * * * * Master mode (SCK is the clock output) Slave mode (SCK is the clock input) Clock Polarity (Idle state of SCK) Data input sample phase (middle or end of data output time) * Clock edge (output data on rising/falling edge of SCK) * Clock Rate (Master mode only) * Slave Select mode (Slave mode only) Figure 14-1 shows the block diagram of the MSSP module, when in SPI mode.
SS
SS Control Enable Edge Select 2 Clock Select SSPM3:SSPM0 SMP:CKE 4 TMR2 output 2 2 Edge Select Prescaler TOSC 4, 16, 64
(
)
SCK
Data to TX/RX in SSPSR TRIS bit
The MSSP consists of a transmit/receive shift register (SSPSR) and a buffer register (SSPBUF). The SSPSR shifts the data in and out of the device, MSb first. The SSPBUF holds the data that was written to the SSPSR, until the received data is ready. Once the 8-bits of data have been received, that byte is moved to the SSPBUF register. Then the buffer full detect bit, BF (SSPSTAT<0>), and the interrupt flag bit, SSPIF, are set. This double buffering of the received data (SSPBUF) allows the next byte to start reception before reading the data that was just received. Any write to the SSPBUF register during transmission/reception of data will be ignored, and the write collision detect bit, WCOL (SSPCON1<7>), will be set. User software must clear the WCOL bit so that it can be determined if the following write(s) to the SSPBUF register completed successfully.
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When the application software is expecting to receive valid data, the SSPBUF should be read before the next byte of data to transfer is written to the SSPBUF. Buffer full bit, BF (SSPSTAT<0>), indicates when SSPBUF has been loaded with the received data (transmission is complete). When the SSPBUF is read, the BF bit is cleared. This data may be irrelevant if the SPI is only a transmitter. Generally the MSSP Interrupt is used to determine when the transmission/reception has completed. The SSPBUF must be read and/or written. If the interrupt method is not going to be used, then software polling can be done to ensure that a write collision does not occur. Example 14-1 shows the loading of the SSPBUF (SSPSR) for data transmission.
EXAMPLE 14-1:
LOADING THE SSPBUF (SSPSR) REGISTER
;Has data been received(transmit complete)? ;No ;WREG reg = contents of SSPBUF ;Save in user RAM, if data is meaningful ;W reg = contents of TXDATA ;New data to xmit
LOOP BTFSS SSPSTAT, BF GOTO LOOP MOVF SSPBUF, W MOVWF RXDATA MOVF TXDATA, W MOVWF SSPBUF
The SSPSR is not directly readable or writable, and can only be accessed by addressing the SSPBUF register. Additionally, the MSSP status register (SSPSTAT) indicates the various status conditions.
port pins. For the pins to behave as the serial port function, some must have their data direction bits (in the TRIS register) appropriately programmed. That is: * * * * * SDI is automatically controlled by the SPI module SDO must have TRISC<5> bit cleared SCK (Master mode) must have TRISC<3> bit cleared SCK (Slave mode) must have TRISC<3> bit set SS must have TRISC<4> bit set
14.3.2
ENABLING SPI I/O
To enable the serial port, SSP enable bit, SSPEN (SSPCON1<5>), must be set. To reset or reconfigure SPI mode, clear the SSPEN bit, re-initialize the SSPCON registers, and then set the SSPEN bit. This configures the SDI, SDO, SCK, and SS pins as serial
Any serial port function that is not desired may be overridden by programming the corresponding data direction (TRIS) register to the opposite value.
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14.3.3 TYPICAL CONNECTION
Figure 14-2 shows a typical connection between two microcontrollers. The master controller (Processor 1) initiates the data transfer by sending the SCK signal. Data is shifted out of both shift registers on their programmed clock edge, and latched on the opposite edge of the clock. Both processors should be programmed to same Clock Polarity (CKP), then both controllers would send and receive data at the same time. Whether the data is meaningful (or dummy data) depends on the application software. This leads to three scenarios for data transmission: * Master sends data -- Slave sends dummy data * Master sends data -- Slave sends data * Master sends dummy data -- Slave sends data
FIGURE 14-2:
SPI MASTER/SLAVE CONNECTION
SPI Master SSPM3:SSPM0 = 00xxb SDO SDI
SPI Slave SSPM3:SSPM0 = 010xb
Serial Input Buffer (SSPBUF)
Serial Input Buffer (SSPBUF)
Shift Register (SSPSR) MSb LSb
SDI
SDO
Shift Register (SSPSR) MSb LSb
SCK PROCESSOR 1
Serial Clock
SCK PROCESSOR 2
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14.3.4 MASTER MODE
The master can initiate the data transfer at any time because it controls the SCK. The master determines when the slave (Processor 2, Figure 14-2) is to broadcast data by the software protocol. In Master mode, the data is transmitted/received as soon as the SSPBUF register is written to. If the SPI is only going to receive, the SDO output could be disabled (programmed as an input). The SSPSR register will continue to shift in the signal present on the SDI pin at the programmed clock rate. As each byte is received, it will be loaded into the SSPBUF register as if a normal received byte (interrupts and status bits appropriately set). This could be useful in receiver applications as a "Line Activity Monitor" mode. The clock polarity is selected by appropriately programming the CKP bit (SSPCON1<4>). This then, would give waveforms for SPI communication as shown in Figure 14-3, Figure 14-5, and Figure 14-6, where the MSB is transmitted first. In Master mode, the SPI clock rate (bit rate) is user programmable to be one of the following: * * * * FOSC/4 (or TCY) FOSC/16 (or 4 * TCY) FOSC/64 (or 16 * TCY) Timer2 output/2
This allows a maximum data rate (at 40 MHz) of 10.00 Mbps. Figure 14-3 shows the waveforms for Master mode. When the CKE bit is set, the SDO data is valid before there is a clock edge on SCK. The change of the input sample is shown based on the state of the SMP bit. The time when the SSPBUF is loaded with the received data is shown.
FIGURE 14-3:
Write to SSPBUF SCK (CKP = 0 CKE = 0) SCK (CKP = 1 CKE = 0) SCK (CKP = 0 CKE = 1) SCK (CKP = 1 CKE = 1) SDO (CKE = 0) SDO (CKE = 1) SDI (SMP = 0) Input Sample (SMP = 0) SDI (SMP = 1) Input Sample (SMP = 1) SSPIF SSPSR to SSPBUF
SPI MODE WAVEFORM (MASTER MODE)
4 Clock modes
bit7 bit7
bit6 bit6
bit5 bit5
bit4 bit4
bit3 bit3
bit2 bit2
bit1 bit1
bit0 bit0
bit7
bit0
bit7
bit0
Next Q4 cycle after Q2
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14.3.5 SLAVE MODE
In Slave mode, the data is transmitted and received as the external clock pulses appear on SCK. When the last bit is latched, the SSPIF interrupt flag bit is set. While in Slave mode, the external clock is supplied by the external clock source on the SCK pin. This external clock must meet the minimum high and low times as specified in the electrical specifications. While in SLEEP mode, the slave can transmit/receive data. When a byte is received, the device will wake-up from SLEEP. the SDO pin is no longer driven, even if in the middle of a transmitted byte, and becomes a floating output. External pull-up/pull-down resistors may be desirable, depending on the application. Note 1: When the SPI is in Slave mode with SS pin control enabled (SSPCON<3:0> = 0100), the SPI module will reset if the SS pin is set to VDD. 2: If the SPI is used in Slave mode with CKE set, then the SS pin control must be enabled. When the SPI module resets, the bit counter is forced to 0. This can be done by either forcing the SS pin to a high level, or clearing the SSPEN bit. To emulate two-wire communication, the SDO pin can be connected to the SDI pin. When the SPI needs to operate as a receiver, the SDO pin can be configured as an input. This disables transmissions from the SDO. The SDI can always be left as an input (SDI function), since it cannot create a bus conflict.
14.3.6
SLAVE SELECT SYNCHRONIZATION
The SS pin allows a Synchronous Slave mode. The SPI must be in Slave mode with SS pin control enabled (SSPCON1<3:0> = 04h). The pin must not be driven low for the SS pin to function as an input. The Data Latch must be high. When the SS pin is low, transmission and reception are enabled and the SDO pin is driven. When the SS pin goes high,
FIGURE 14-4:
SLAVE SYNCHRONIZATION WAVEFORM
SS
SCK (CKP = 0 CKE = 0) SCK (CKP = 1 CKE = 0)
Write to SSPBUF
SDO
bit7
bit6
bit7
bit0
SDI (SMP = 0) Input Sample (SMP = 0) SSPIF Interrupt Flag SSPSR to SSPBUF
bit0 bit7 bit7
Next Q4 cycle after Q2
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FIGURE 14-5:
SS optional SCK (CKP = 0 CKE = 0) SCK (CKP = 1 CKE = 0) Write to SSPBUF SDO SDI (SMP = 0) Input Sample (SMP = 0) SSPIF Interrupt Flag SSPSR to SSPBUF bit7 bit6 bit5 bit4 bit3 bit2 bit1 bit0
SPI MODE WAVEFORM (SLAVE MODE WITH CKE = 0)
bit7
bit0
Next Q4 cycle after Q2
FIGURE 14-6:
SS not optional SCK (CKP = 0 CKE = 1) SCK (CKP = 1 CKE = 1) Write to SSPBUF SDO SDI (SMP = 0) Input Sample (SMP = 0) SSPIF Interrupt Flag SSPSR to SSPBUF
SPI MODE WAVEFORM (SLAVE MODE WITH CKE = 1)
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
bit7
bit0
Next Q4 cycle after Q2
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PIC18CXX2
14.3.7 SLEEP OPERATION 14.3.9 BUS MODE COMPATIBILITY
In Master mode, all module clocks are halted, and the transmission/reception will remain in that state until the device wakes from SLEEP. After the device returns to normal mode, the module will continue to transmit/ receive data. In Slave mode, the SPI transmit/receive shift register operates asynchronously to the device. This allows the device to be placed in SLEEP mode, and data to be shifted into the SPI transmit/receive shift register. When all 8-bits have been received, the MSSP interrupt flag bit will be set and if enabled, will wake the device from SLEEP. Table 14-1 shows the compatibility between the standard SPI modes and the states of the CKP and CKE control bits.
TABLE 14-1:
SPI BUS MODES
Control Bits State CKP 0 0 1 1 CKE 1 0 1 0
Standard SPI Mode Terminology 0, 0, 1, 1, 0 1 0 1
14.3.8
EFFECTS OF A RESET
A RESET disables the MSSP module and terminates the current transfer.
There is also a SMP bit which controls when the data is sampled.
TABLE 14-2:
Name INTCON PIR1 PIE1 IPR1 TRISC SSPBUF SSPCON TRISA SSPSTAT
REGISTERS ASSOCIATED WITH SPI OPERATION
Bit 7 Bit 6 PEIE/ GIEL ADIF ADIE ADIP Bit 5 TMR0IE RCIF RCIE RCIP Bit 4 INT0IE TXIF TXIE TXIP Bit 3 RBIE SSPIF SSPIE SSPIP Bit 2 TMR0IF CCP1IF CCP1IE CCP1IP Bit 1 INT0IF TMR2IF TMR2IE TMR2IP Bit 0 RBIF TMR1IF TMR1IE TMR1IP Value on POR, BOR Value on all other RESETS
GIE/GIEH PSPIF (1) PSPIE
(1)
0000 000x 0000 000u 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 1111 1111 1111 1111 xxxx xxxx uuuu uuuu
PSPIP (1)
PORTC Data Direction Register Synchronous Serial Port Receive Buffer/Transmit Register WCOL -- SMP SSPOV SSPEN CKP SSPM3 SSPM2 SSPM1 SSPM0 PORTA Data Direction Register CKE D/A P S R/W UA BF
0000 0000 0000 0000 --11 1111 --11 1111 0000 0000 0000 0000
Legend: x = unknown, u = unchanged, - = unimplemented, read as '0'. Shaded cells are not used by the MSSP in SPI mode. Note 1: The PSPIF, PSPIE and PSPIP bits are reserved on the PIC18C2X2 devices. Always maintain these bits clear.
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PIC18CXX2
14.4 MSSP I2C Operation
The MSSP module in I 2C mode, fully implements all master and slave functions (including general call support) and provides interrupts on START and STOP bits in hardware to determine a free bus (multi-master function). The MSSP module implements the standard mode specifications, as well as 7-bit and 10-bit addressing. Two pins are used for data transfer. These are the RC3/ SCK/SCL pin, which is the clock (SCL), and the RC4/ SDI/SDA pin, which is the data (SDA). The user must configure these pins as inputs or outputs through the TRISC<4:3> bits. The MSSP module functions are enabled by setting MSSP enable bit SSPEN (SSPCON<5>). The SSPCON1 register allows control of the I 2C operation. Four mode selection bits (SSPCON<3:0>) allow one of the following I 2C modes to be selected: * * * * I2C Master mode, clock = OSC/4 (SSPADD +1) I 2C Slave mode (7-bit address) I 2C Slave mode (10-bit address) I 2C Slave mode (7-bit address), with START and STOP bit interrupts enabled * I 2C Slave mode (10-bit address), with START and STOP bit interrupts enabled * I 2C Firmware controlled master operation, slave is idle
Selection of any I 2C mode with the SSPEN bit set, forces the SCL and SDA pins to be open drain, provided these pins are programmed to be inputs by setting the appropriate TRISC bits.
FIGURE 14-7:
MSSP BLOCK DIAGRAM (I2C MODE)
Internal Data Bus Read SSPBUF reg Shift Clock SSPSR reg Write
14.4.1
SLAVE MODE
In Slave mode, the SCL and SDA pins must be configured as inputs (TRISC<4:3> set). The MSSP module will override the input state with the output data when required (slave-transmitter). When an address is matched or the data transfer after an address match is received, the hardware automatically will generate the Acknowledge (ACK) pulse and load the SSPBUF register with the received value currently in the SSPSR register.
RC3/SCK/SCL
RC4/ SDI/ SDA
MSb
LSb
There are certain conditions that will cause the MSSP module not to give this ACK pulse. These are if either (or both):
Addr Match
Match Detect
a) b)
SSPADD reg START and STOP bit Detect Set, Reset S, P bits (SSPSTAT reg)
The buffer full bit BF (SSPSTAT<0>) was set before the transfer was received. The overflow bit SSPOV (SSPCON<6>) was set before the transfer was received.
In this case, the SSPSR register value is not loaded into the SSPBUF, but bit SSPIF (PIR1<3>) is set. The BF bit is cleared by reading the SSPBUF register, while bit SSPOV is cleared through software. The SCL clock input must have a minimum high and low for proper operation. The high and low times of the I2C specification, as well as the requirement of the MSSP module, are shown in timing parameter #100 and parameter #101.
The MSSP module has six registers for I2C operation. These are the: * * * * * MSSP Control Register1 (SSPCON1) MSSP Control Register2 (SSPCON2) MSSP Status Register (SSPSTAT) Serial Receive/Transmit Buffer (SSPBUF) MSSP Shift Register (SSPSR) - Not directly accessible * MSSP Address Register (SSPADD)
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PIC18CXX2
14.4.1.1 Addressing 14.4.1.2 Reception
Once the MSSP module has been enabled, it waits for a START condition to occur. Following the START condition, the 8-bits are shifted into the SSPSR register. All incoming bits are sampled with the rising edge of the clock (SCL) line. The value of register SSPSR<7:1> is compared to the value of the SSPADD register. The address is compared on the falling edge of the eighth clock (SCL) pulse. If the addresses match, and the BF and SSPOV bits are clear, the following events occur: a) b) c) d) The SSPSR register value is loaded into the SSPBUF register. The buffer full bit BF is set. An ACK pulse is generated. MSSP interrupt flag bit SSPIF (PIR1<3>) is set (interrupt is generated if enabled) on the falling edge of the ninth SCL pulse. When the R/W bit of the address byte is clear and an address match occurs, the R/W bit of the SSPSTAT register is cleared. The received address is loaded into the SSPBUF register. When the address byte overflow condition exists, then no Acknowledge (ACK) pulse is given. An overflow condition is defined as either bit BF (SSPSTAT<0>) is set, or bit SSPOV (SSPCON<6>) is set. An MSSP interrupt is generated for each data transfer byte. Flag bit SSPIF (PIR1<3>) must be cleared in software. The SSPSTAT register is used to determine the status of the byte.
14.4.1.3
Transmission
In 10-bit address mode, two address bytes need to be received by the slave. The five Most Significant bits (MSbs) of the first address byte specify if this is a 10-bit address. Bit R/W (SSPSTAT<2>) must specify a write so the slave device will receive the second address byte. For a 10-bit address, the first byte would equal `1111 0 A9 A8 0', where A9 and A8 are the two MSbs of the address. The sequence of events for 10-bit address is as follows, with steps 7-9 for slave-transmitter: 1. 2. Receive first (high) byte of Address (bits SSPIF, BF and bit UA (SSPSTAT<1>) are set). Update the SSPADD register with second (low) byte of Address (clears bit UA and releases the SCL line). Read the SSPBUF register (clears bit BF) and clear flag bit SSPIF. Receive second (low) byte of Address (bits SSPIF, BF, and UA are set). Update the SSPADD register with the first (high) byte of Address. If match releases SCL line, this will clear bit UA. Read the SSPBUF register (clears bit BF) and clear flag bit SSPIF. Receive Repeated START condition. Receive first (high) byte of Address (bits SSPIF and BF are set). Read the SSPBUF register (clears bit BF) and clear flag bit SSPIF.
When the R/W bit of the incoming address byte is set and an address match occurs, the R/W bit of the SSPSTAT register is set. The received address is loaded into the SSPBUF register. The ACK pulse will be sent on the ninth bit and pin RC3/SCK/SCL is held low. The transmit data must be loaded into the SSPBUF register, which also loads the SSPSR register. Then pin RC3/SCK/SCL should be enabled by setting bit CKP (SSPCON<4>). The master must monitor the SCL pin prior to asserting another clock pulse. The slave devices may be holding off the master by stretching the clock. The eight data bits are shifted out on the falling edge of the SCL input. This ensures that the SDA signal is valid during the SCL high time (Figure 14-9). An MSSP interrupt is generated for each data transfer byte. The SSPIF bit must be cleared in software and the SSPSTAT register is used to determine the status of the byte. The SSPIF bit is set on the falling edge of the ninth clock pulse. As a slave-transmitter, the ACK pulse from the master-receiver is latched on the rising edge of the ninth SCL input pulse. If the SDA line is high (not ACK), then the data transfer is complete. When the ACK is latched by the slave, the slave logic is reset (resets SSPSTAT register) and the slave monitors for another occurrence of the START bit. If the SDA line was low (ACK), the transmit data must be loaded into the SSPBUF register, which also loads the SSPSR register. Pin RC3/SCK/SCL should be enabled by setting bit CKP.
3. 4. 5.
6. 7. 8. 9.
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PIC18CXX2
FIGURE 14-8:
SDA
I 2C SLAVE MODE WAVEFORMS FOR RECEPTION (7-BIT ADDRESS)
Receiving Address Receiving Data R/W=0 Receiving Data Not ACK ACK ACK A7 A6 A5 A4 A3 A2 A1 D7 D6 D5 D4 D3 D2 D1 D0 D7 D6 D5 D4 D3 D2 D1 D0 S 1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9 P
SCL SSPIF
Bus Master terminates transfer Cleared in software SSPBUF register is read
BF (SSPSTAT<0>)
SSPOV (SSPCON1<6>) Bit SSPOV is set because the SSPBUF register is still full. ACK is not sent.
FIGURE 14-9:
I 2C SLAVE MODE WAVEFORMS FOR TRANSMISSION (7-BIT ADDRESS)
Receiving Address R/W = 1 A1 ACK D7 D6 D5 D4 Transmitting Data D3 D2 D1 D0 R/W = 0 Not ACK
SDA
A7
A6
A5
A4
A3
A2
SCL
S
1 2 Data in sampled
3
4
5
6
7
8
9
1 SCL held low while CPU responds to SSPIF
2
3
4
5
6
7
8
9
P
SSPIF BF (SSPSTAT<0>) Cleared in software SSPBUF is written in software CKP (SSPCON1<4>) Set bit after writing to SSPBUF (the SSPBUF must be written to before the CKP bit can be set) From SSP Interrupt Service Routine
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FIGURE 14-10:
2001 Microchip Technology Inc.
Master sends NACK Transmit is complete Clock is held low until update of SSPADD has taken place Receive Second Byte of Address Receive First Byte of Address ACK 1 1 1 1 0 A9 A8 A7 A6 A5 A4 A3 A2 A1 A0 R/W=1 ACK Transmitting Data Byte D7 D6 D5 D4 D3 D2 D1 D0 ACK 1 0 A9 A8 ACK 4 Sr 5 6 7 8 9 1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9 P CKP has to be set for clock to be released Cleared in software Cleared in software Cleared in software Bus Master terminates transfer Dummy read of SSPBUF to clear BF flag Dummy read of SSPBUF to clear BF flag Write of SSPBUF initiates transmit Cleared by hardware when SSPADD is updated. UA is set indicating that SSPADD needs to be updated Cleared by hardware when SSPADD is updated.
Receive First Byte of Address R/W = 0
SDA
1
1
1
SCL
S
1
2
3
SSPIF
(PIR1<3>)
BF (SSPSTAT<0>)
SSPBUF is written with contents of SSPSR
UA (SSPSTAT<1>)
I2C SLAVE MODE WAVEFORM (TRANSMISSION 10-BIT ADDRESS)
PIC18CXX2
UA is set indicating that the SSPADD needs to be updated
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FIGURE 14-11:
DS39026C-page 132
Clock is held low until update of SSPADD has taken place R/W = 0 A8 ACK A7 A6 A5 A4 A3 A2 A1 A0 D7 D6 ACK D5 Receive Second Byte of Address Receive Data Byte D4 D3 D2 D1 R/W = 1 D0 ACK Bus Master terminates transfer 1 1 0 A9 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9 1 2 3 4 5 6 7 8 9 P Cleared in software Cleared in software SSPBUF is written with contents of SSPSR Dummy read of SSPBUF to clear BF flag Dummy read of SSPBUF to clear BF flag Read of SSPBUF clears BF flag
PIC18CXX2
Receive First Byte of Address
SDA
1
1
SCL
S
1
2
SSPIF
(PIR1<3>)
BF (SSPSTAT<0>)
UA (SSPSTAT<1>) UA is set indicating that the SSPADD needs to be updated Cleared by hardware when SSPADD is updated with low byte of address. UA is set indicating that SSPADD needs to be updated Cleared by hardware when SSPADD is updated with high byte of address.
I2C SLAVE MODE WAVEFORM (RECEPTION 10-BIT ADDRESS)
2001 Microchip Technology Inc.
PIC18CXX2
14.4.2 GENERAL CALL ADDRESS SUPPORT
The addressing procedure for the I2C bus is such that the first byte after the START condition usually determines which device will be the slave addressed by the master. The exception is the general call address which can address all devices. When this address is used, all devices should, in theory, respond with an acknowledge. The general call address is one of eight addresses reserved for specific purposes by the I2C protocol. It consists of all 0's with R/W = 0. The general call address is recognized when the General Call Enable bit (GCEN) is enabled (SSPCON2<7> is set). Following a START bit detect, 8-bits are shifted into the SSPSR and the address is compared against the SSPADD. It is also compared to the general call address and fixed in hardware. If the general call address matches, the SSPSR is transferred to the SSPBUF, the BF flag bit is set (eighth bit), and on the falling edge of the ninth bit (ACK bit), the SSPIF interrupt flag bit is set. When the interrupt is serviced, the source for the interrupt can be checked by reading the contents of the SSPBUF. The value can be used to determine if the address was device specific or a general call address. In 10-bit mode, the SSPADD is required to be updated for the second half of the address to match, and the UA bit is set (SSPSTAT<1>). If the general call address is sampled when the GCEN bit is set, while the slave is configured in 10-bit address mode, then the second half of the address is not necessary, the UA bit will not be set, and the slave will begin receiving data after the Acknowledge (Figure 14-12).
FIGURE 14-12:
SLAVE MODE GENERAL CALL ADDRESS SEQUENCE (7 OR 10-BIT ADDRESS MODE)
Address is compared to General Call Address after ACK, set interrupt R/W = 0 ACK D7 Receiving Data D6 D5 D4 D3 D2 D1 D0 ACK
SDA SCL S SSPIF BF (SSPSTAT<0>) 1
General Call Address
2
3
4
5
6
7
8
9
1
2
3
4
5
6
7
8
9
Cleared in software SSPBUF is read SSPOV (SSPCON1<6>) '0'
GCEN (SSPCON2<7>)
'1'
14.4.3
MASTER MODE
The following events will cause SSP Interrupt Flag bit, SSPIF, to be set (SSP interrupt, if enabled): * * * * * START condition STOP condition Data transfer byte transmitted/received Acknowledge Transmit Repeated START
Master mode of operation is supported by interrupt generation on the detection of the START and STOP conditions. The STOP (P) and START (S) bits are cleared from a RESET or when the MSSP module is disabled. Control of the I 2C bus may be taken when the P bit is set, or the bus is idle, with both the S and P bits clear. In Master mode, the SCL and SDA lines are manipulated by the MSSP hardware.
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PIC18CXX2
14.4.4 I2C MASTER MODE SUPPORT
Note: The MSSP module, when configured in I2C Master mode, does not allow queueing of events. For instance, the user is not allowed to initiate a START condition and immediately write the SSPBUF register to imitate transmission, before the START condition is complete. In this case, the SSPBUF will not be written to and the WCOL bit will be set, indicating that a write to the SSPBUF did not occur. Master mode is enabled by setting and clearing the appropriate SSPM bits in SSPCON1 and by setting the SSPEN bit. Once Master mode is enabled, the user has six options. 1. 2. 3. 4. 5. 6. Assert a START condition on SDA and SCL. Assert a Repeated START condition on SDA and SCL. Write to the SSPBUF register initiating transmission of data/address. Generate a STOP condition on SDA and SCL. Configure the I2C port to receive data. Generate an Acknowledge condition at the end of a received byte of data.
FIGURE 14-13:
MSSP BLOCK DIAGRAM (I2C MASTER MODE)
Internal Data Bus Read SSPBUF Write Baud Rate Generator Clock Arbitrate/WCOL Detect (hold off clock source) 2001 Microchip Technology Inc. Shift Clock SSPSR Receive Enable MSb LSb SSPM3:SSPM0 SSPADD<6:0>
SDA SDA in
SCL
SCL in Bus Collision
START bit Detect STOP bit Detect Write Collision Detect Clock Arbitration State Counter for end of XMIT/RCV
Set/Reset, S, P, WCOL (SSPSTAT) Set SSPIF, BCLIF Reset ACKSTAT, PEN (SSPCON2)
DS39026C-page 134
Clock Cntl
START bit, STOP bit, Acknowledge Generate
PIC18CXX2
14.4.4.1 I2C Master Mode Operation
A typical transmit sequence would go as follows: a) The user generates a START condition by setting the START enable bit, SEN (SSPCON2<0>). SSPIF is set. The MSSP module will wait the required start time before any other operation takes place. The user loads the SSPBUF with the address to transmit. Address is shifted out the SDA pin until all 8 bits are transmitted. The MSSP module shifts in the ACK bit from the slave device and writes its value into the SSPCON2 register (SSPCON2<6>). The MSSP module generates an interrupt at the end of the ninth clock cycle by setting the SSPIF bit. The user loads the SSPBUF with eight bits of data. Data is shifted out the SDA pin until all 8 bits are transmitted. The MSSP module shifts in the ACK bit from the slave device and writes its value into the SSPCON2 register (SSPCON2<6>). The MSSP module generates an interrupt at the end of the ninth clock cycle by setting the SSPIF bit. The user generates a STOP condition by setting the STOP enable bit, PEN (SSPCON2<2>). Interrupt is generated once the STOP condition is complete. The master device generates all of the serial clock pulses and the START and STOP conditions. A transfer is ended with a STOP condition or with a Repeated START condition. Since the Repeated START condition is also the beginning of the next serial transfer, the I2C bus will not be released. In Master Transmitter mode, serial data is output through SDA, while SCL outputs the serial clock. The first byte transmitted contains the slave address of the receiving device (7 bits) and the Read/Write (R/W) bit. In this case, the R/W bit will be logic '0'. Serial data is transmitted 8 bits at a time. After each byte is transmitted, an Acknowledge bit is received. START and STOP conditions are output to indicate the beginning and the end of a serial transfer. In Master Receive mode, the first byte transmitted contains the slave address of the transmitting device (7 bits) and the R/W bit. In this case, the R/W bit will be logic '1'. Thus, the first byte transmitted is a 7-bit slave address followed by a '1' to indicate receive bit. Serial data is received via SDA, while SCL outputs the serial clock. Serial data is received 8 bits at a time. After each byte is received, an Acknowledge bit is transmitted. START and STOP conditions indicate the beginning and end of transmission. The baud rate generator used for the SPI mode operation is now used to set the SCL clock frequency for either 100 kHz, 400 kHz, or 1 MHz I2C operation. The baud rate generator reload value is contained in the lower 7 bits of the SSPADD register. The baud rate generator will automatically begin counting on a write to the SSPBUF. Once the given operation is complete, (i.e., transmission of the last data bit is followed by ACK), the internal clock will automatically stop counting and the SCL pin will remain in its last state.
b)
c) d) e)
f)
g) h) i)
j)
k) l)
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PIC18CXX2
14.4.5
I2C
BAUD RATE GENERATOR
In Master mode, the reload value for the BRG is located in the lower 7 bits of the SSPADD register (Figure 14-14). When the BRG is loaded with this value, the BRG counts down to 0 and stops until another reload has taken place. The BRG count is dec-
remented twice per instruction cycle (TCY) on the Q2 and Q4 clocks. In I2C Master mode, the BRG is reloaded automatically. If Clock Arbitration is taking place, for instance, the BRG will be reloaded when the SCL pin is sampled high (Figure 14-15).
FIGURE 14-14:
BAUD RATE GENERATOR BLOCK DIAGRAM
SSPM3:SSPM0 SSPADD<6:0>
SSPM3:SSPM0 SCL
Reload Control CLKOUT
Reload
BRG Down Counter
FOSC/4
FIGURE 14-15:
SDA
BAUD RATE GENERATOR TIMING WITH CLOCK ARBITRATION
DX DX-1 SCL allowed to transition high
SCL de-asserted but slave holds SCL low (clock arbitration) SCL BRG decrements on Q2 and Q4 cycles BRG Value 03h 02h 01h 00h (hold off)
03h
02h
SCL is sampled high, reload takes place and BRG starts its count. BRG Reload
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PIC18CXX2
14.4.6 I2C MASTER MODE START CONDITION TIMING 14.4.6.1 WCOL Status Flag
If the user writes the SSPBUF when a START sequence is in progress, the WCOL is set and the contents of the buffer are unchanged (the write doesn't occur). Note: Because queueing of events is not allowed, writing to the lower 5 bits of SSPCON2 is disabled until the START condition is complete.
To initiate a START condition, the user sets the START condition enable bit, SEN (SSPCON2<0>). If the SDA and SCL pins are sampled high, the baud rate generator is reloaded with the contents of SSPADD<6:0> and starts its count. If SCL and SDA are both sampled high when the baud rate generator times out (TBRG), the SDA pin is driven low. The action of the SDA being driven low, while SCL is high, is the START condition and causes the S bit (SSPSTAT<3>) to be set. Following this, the baud rate generator is reloaded with the contents of SSPADD<6:0> and resumes its count. When the baud rate generator times out (TBRG), the SEN bit (SSPCON2<0>) will be automatically cleared by hardware, the baud rate generator is suspended leaving the SDA line held low and the START condition is complete. Note: If, at the beginning of the START condition, the SDA and SCL pins are already sampled low, or if during the START condition, the SCL line is sampled low before the SDA line is driven low, a bus collision occurs, the Bus Collision Interrupt Flag, BCLIF is set, the START condition is aborted, and the I2C module is reset into its IDLE state.
FIGURE 14-16:
FIRST START BIT TIMING
Set S bit (SSPSTAT<3>) SDA = 1, SCL = 1 At completion of START bit, Hardware clears SEN bit and sets SSPIF bit TBRG Write to SSPBUF occurs here 1st Bit SDA TBRG 2nd Bit
Write to SEN bit occurs here.
TBRG
SCL S
TBRG
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PIC18CXX2
14.4.7 I2C MASTER MODE REPEATED START CONDITION TIMING
Immediately following the SSPIF bit getting set, the user may write the SSPBUF with the 7-bit address in 7-bit mode, or the default first address in 10-bit mode. After the first eight bits are transmitted and an ACK is received, the user may then transmit an additional eight bits of address (10-bit mode), or eight bits of data (7-bit mode).
A Repeated START condition occurs when the RSEN bit (SSPCON2<1>) is programmed high and the I2C logic module is in the idle state. When the RSEN bit is set, the SCL pin is asserted low. When the SCL pin is sampled low, the baud rate generator is loaded with the contents of SSPADD<5:0> and begins counting. The SDA pin is released (brought high) for one baud rate generator count (TBRG). When the baud rate generator times out, if SDA is sampled high, the SCL pin will be de-asserted (brought high). When SCL is sampled high, the baud rate generator is reloaded with the contents of SSPADD<6:0> and begins counting. SDA and SCL must be sampled high for one TBRG. This action is then followed by assertion of the SDA pin (SDA = 0) for one TBRG, while SCL is high. Following this, the RSEN bit (SSPCON2<1>) will be automatically cleared and the baud rate generator will not be reloaded, leaving the SDA pin held low. As soon as a START condition is detected on the SDA and SCL pins, the S bit (SSPSTAT<3>) will be set. The SSPIF bit will not be set until the baud rate generator has timed out. Note 1: If RSEN is programmed while any other event is in progress, it will not take effect. 2: A bus collision during the Repeated START condition occurs if: * SDA is sampled low when SCL goes from low to high. * SCL goes low before SDA is asserted low. This may indicate that another master is attempting to transmit a data "1".
14.4.7.1
WCOL Status Flag
If the user writes the SSPBUF when a Repeated START sequence is in progress, the WCOL is set and the contents of the buffer are unchanged (the write doesn't occur). Note: Because queueing of events is not allowed, writing of the lower 5 bits of SSPCON2 is disabled until the Repeated START condition is complete.
FIGURE 14-17:
REPEAT START CONDITION WAVEFORM
Set S (SSPSTAT<3>) Write to SSPCON2 occurs here. SDA = 1, SCL (no change) SDA = 1, SCL = 1 At completion of START bit, hardware clear RSEN bit and set SSPIF TBRG 1st Bit SDA Falling edge of ninth clock End of Xmit Write to SSPBUF occurs here. TBRG TBRG Sr = Repeated START
TBRG
TBRG
SCL
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PIC18CXX2
14.4.8 I2C MASTER MODE TRANSMISSION 14.4.8.3 ACKSTAT Status Flag
In Transmit mode, the ACKSTAT bit (SSPCON2<6>) is cleared when the slave has sent an Acknowledge (ACK = 0), and is set when the slave does not Acknowledge (ACK = 1). A slave sends an Acknowledge when it has recognized its address (including a general call), or when the slave has properly received its data.
Transmission of a data byte, a 7-bit address, or the other half of a 10-bit address, is accomplished by simply writing a value to the SSPBUF register. This action will set the buffer full flag bit, BF, and allow the baud rate generator to begin counting and start the next transmission. Each bit of address/data will be shifted out onto the SDA pin after the falling edge of SCL is asserted (see data hold time specification parameter 106). SCL is held low for one baud rate generator rollover count (TBRG). Data should be valid before SCL is released high (see Data setup time specification parameter 107). When the SCL pin is released high, it is held that way for TBRG. The data on the SDA pin must remain stable for that duration and some hold time after the next falling edge of SCL. After the eighth bit is shifted out (the falling edge of the eighth clock), the BF flag is cleared and the master releases SDA. allowing the slave device being addressed to respond with an ACK bit during the ninth bit time, if an address match occurs, or if data was received properly. The status of ACK is written into the ACKDT bit on the falling edge of the ninth clock. If the master receives an Acknowledge, the Acknowledge status bit, ACKSTAT, is cleared. If not, the bit is set. After the ninth clock, the SSPIF bit is set and the master clock (baud rate generator) is suspended until the next data byte is loaded into the SSPBUF, leaving SCL low and SDA unchanged (Figure 14-18). After the write to the SSPBUF, each bit of address will be shifted out on the falling edge of SCL until all seven address bits and the R/W bit are completed. On the falling edge of the eighth clock, the master will de-assert the SDA pin, allowing the slave to respond with an Acknowledge. On the falling edge of the ninth clock, the master will sample the SDA pin to see if the address was recognized by a slave. The status of the ACK bit is loaded into the ACKSTAT status bit (SSPCON2<6>). Following the falling edge of the ninth clock transmission of the address, the SSPIF is set, the BF flag is cleared and the baud rate generator is turned off until another write to the SSPBUF takes place, holding SCL low and allowing SDA to float.
14.4.9
I2C MASTER MODE RECEPTION
Master mode reception is enabled by programming the receive enable bit, RCEN (SSPCON2<3>). Note: The MSSP module must be in an IDLE state before the RCEN bit is set, or the RCEN bit will be disregarded.
The baud rate generator begins counting, and on each rollover, the state of the SCL pin changes (high to low/ low to high) and data is shifted into the SSPSR. After the falling edge of the eighth clock, the receive enable flag is automatically cleared, the contents of the SSPSR are loaded into the SSPBUF, the BF flag bit is set, the SSPIF flag bit is set and the baud rate generator is suspended from counting, holding SCL low. The MSSP is now in IDLE state, awaiting the next command. When the buffer is read by the CPU, the BF flag bit is automatically cleared. The user can then send an Acknowledge bit at the end of reception, by setting the Acknowledge sequence enable bit, ACKEN (SSPCON2<4>).
14.4.9.1
BF Status Flag
In receive operation, the BF bit is set when an address or data byte is loaded into SSPBUF from SSPSR. It is cleared when the SSPBUF register is read.
14.4.9.2
SSPOV Status Flag
In receive operation, the SSPOV bit is set when 8 bits are received into the SSPSR and the BF flag bit is already set from a previous reception.
14.4.9.3
WCOL Status Flag
14.4.8.1
BF Status Flag
If the user writes the SSPBUF when a receive is already in progress (i.e., SSPSR is still shifting in a data byte), the WCOL bit is set and the contents of the buffer are unchanged (the write doesn't occur).
In Transmit mode, the BF bit (SSPSTAT<0>) is set when the CPU writes to SSPBUF and is cleared, when all 8 bits are shifted out.
14.4.8.2
WCOL Status Flag
If the user writes the SSPBUF when a transmit is already in progress, (i.e., SSPSR is still shifting out a data byte), the WCOL is set and the contents of the buffer are unchanged (the write doesn't occur). WCOL must be cleared in software.
2001 Microchip Technology Inc.
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FIGURE 14-18:
DS39026C-page 140
Write SSPCON2<0> SEN = 1 START condition begins From slave clear ACKSTAT bit SSPCON2<6> R/W = 0 A1 ACK = 0 D7 D6 D5 D4 D3 D2 D1 Transmitting Data or Second Half of 10-bit Address D0 ACK SEN = 0 Transmit Address to Slave SDA A7 SSPBUF written with 7 bit address and R/W start transmit SCL S 1 2 3 4 5 6 7 8 9 1 SCL held low while CPU responds to SSPIF 2 3 4 5 6 7 8 9 P A6 A5 A4 A3 A2 ACKSTAT in SSPCON2 = 1 SSPIF cleared in software Cleared in software service routine From SSP interrupt Cleared in software BF (SSPSTAT<0>) SSPBUF written SEN After START condition SEN cleared by hardware. SSPBUF is written in software PEN
PIC18CXX2
I 2C MASTER MODE WAVEFORM (TRANSMISSION, 7 OR 10-BIT ADDRESS)
2001 Microchip Technology Inc.
R/W
FIGURE 14-19:
Write to SSPCON2<4> to start Acknowledge sequence SDA = ACKDT (SSPCON2<5>) = 0 Master configured as a receiver by programming SSPCON2<3>, (RCEN = 1) ACK from Slave R/W = 1 Receiving Data from Slave ACK Receiving Data from Slave RCEN cleared automatically ACK RCEN = 1 start next receive RCEN cleared automatically ACK from Master SDA = ACKDT = 0 Set ACKEN start Acknowledge sequence SDA = ACKDT = 1 PEN bit = 1 written here
2001 Microchip Technology Inc.
A1 D0 D7 D6 D5 D4 D3 D2 D1 D7 D6 D5 D4 D3 D2 D1 D0
ACK ACK is not sent Bus Master terminates transfer
Write to SSPCON2<0> (SEN = 1) Begin START Condition
SEN = 0 Write to SSPBUF occurs here Start XMIT
Transmit Address to Slave
SDA
A7
A6 A5 A4 A3 A2
SCL
S
Set SSPIF interrupt at end of receive
1 5 1 2 3 4 5 1 2 3 4
2
3 4 8 6 7 8 9
6
7 9
5
6
7
8
9
Set SSPIF at end of receive
P
Set SSPIF interrupt at end of Acknowledge sequence
Data shifted in on falling edge of CLK
SSPIF
Cleared in software Cleared in software
Set SSPIF interrupt at end of Acknowledge sequence Cleared in software Cleared in software
SDA = 0, SCL = 1 while CPU responds to SSPIF
Cleared in software
Set P bit (SSPSTAT<4>) and SSPIF
BF (SSPSTAT<0>)
Last bit is shifted into SSPSR and contents are unloaded into SSPBUF
SSPOV
SSPOV is set because SSPBUF is still full
I 2C MASTER MODE WAVEFORM (RECEPTION, 7-BIT ADDRESS)
PIC18CXX2
ACKEN
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PIC18CXX2
14.4.10 ACKNOWLEDGE SEQUENCE TIMING 14.4.11 STOP CONDITION TIMING
A STOP bit is asserted on the SDA pin at the end of a receive/transmit by setting the STOP sequence enable bit, PEN (SSPCON2<2>). At the end of a receive/transmit, the SCL line is held low after the falling edge of the ninth clock. When the PEN bit is set, the master will assert the SDA line low. When the SDA line is sampled low, the baud rate generator is reloaded and counts down to 0. When the baud rate generator times out, the SCL pin will be brought high, and one TBRG (baud rate generator rollover count) later, the SDA pin will be de-asserted. When the SDA pin is sampled high while SCL is high, the P bit (SSPSTAT<4>) is set. A TBRG later, the PEN bit is cleared and the SSPIF bit is set (Figure 14-21).
An Acknowledge sequence is enabled by setting the Acknowledge sequence enable bit, ACKEN (SSPCON2<4>). When this bit is set, the SCL pin is pulled low and the contents of the Acknowledge data bit is presented on the SDA pin. If the user wishes to generate an Acknowledge, then the ACKDT bit should be cleared. If not, the user should set the ACKDT bit before starting an Acknowledge sequence. The baud rate generator then counts for one rollover period (TBRG) and the SCL pin is de-asserted (pulled high). When the SCL pin is sampled high (clock arbitration), the baud rate generator counts for TBRG. The SCL pin is then pulled low. Following this, the ACKEN bit is automatically cleared, the baud rate generator is turned off and the MSSP module then goes into IDLE mode (Figure 14-20).
14.4.11.1
WCOL Status Flag
14.4.10.1
WCOL Status Flag
If the user writes the SSPBUF when an Acknowledge sequence is in progress, then WCOL is set and the contents of the buffer are unchanged (the write doesn't occur).
If the user writes the SSPBUF when a STOP sequence is in progress, then the WCOL bit is set and the contents of the buffer are unchanged (the write doesn't occur).
FIGURE 14-20:
ACKNOWLEDGE SEQUENCE WAVEFORM
Acknowledge sequence starts here, Write to SSPCON2 ACKEN = 1, ACKDT = 0 TBRG SDA D0 ACK TBRG ACKEN automatically cleared
SCL
8
9
SSPIF
Set SSPIF at the end of receive
Cleared in software
Cleared in software Set SSPIF at the end of Acknowledge sequence
Note: TBRG = one baud rate generator period.
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PIC18CXX2
FIGURE 14-21: STOP CONDITION RECEIVE OR TRANSMIT MODE
Write to SSPCON2 Set PEN Falling edge of 9th clock TBRG SCL SCL = 1 for Tbrg, followed by SDA = 1 for Tbrg after SDA sampled high. P bit (SSPSTAT<4>) is set PEN bit (SSPCON2<2>) is cleared by hardware and the SSPIF bit is set
SDA
ACK P TBRG TBRG TBRG
SCL brought high after TBRG SDA asserted low before rising edge of clock to setup STOP condition.
Note: TBRG = one baud rate generator period.
14.4.12
CLOCK ARBITRATION
14.4.13
SLEEP OPERATION
Clock arbitration occurs when the master, during any receive, transmit, or Repeated START/STOP condition, de-asserts the SCL pin (SCL allowed to float high). When the SCL pin is allowed to float high, the baud rate generator (BRG) is suspended from counting until the SCL pin is actually sampled high. When the SCL pin is sampled high, the baud rate generator is reloaded with the contents of SSPADD<6:0> and begins counting. This ensures that the SCL high time will always be at least one BRG rollover count, in the event that the clock is held low by an external device (Figure 14-22).
While in SLEEP mode, the I2C module can receive addresses or data, and when an address match or complete byte transfer occurs, wake the processor from SLEEP (if the MSSP interrupt is enabled).
14.4.14
EFFECT OF A RESET
A RESET disables the MSSP module and terminates the current transfer.
FIGURE 14-22:
CLOCK ARBITRATION TIMING IN MASTER TRANSMIT MODE
BRG overflow, Release SCL, If SCL = 1, Load BRG with SSPADD<6:0>, and start count to measure high time interval
BRG overflow occurs, Release SCL, Slave device holds SCL low.
SCL = 1 BRG starts counting clock high interval.
SCL
SCL line sampled once every machine cycle (TOSC 4). Hold off BRG until SCL is sampled high.
SDA TBRG TBRG TBRG
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PIC18CXX2
14.4.15 MULTI-MASTER MODE
In Multi-Master mode, the interrupt generation on the detection of the START and STOP conditions allows the determination of when the bus is free. The STOP (P) and START (S) bits are cleared from a RESET, or when the MSSP module is disabled. Control of the I 2C bus may be taken when the P bit (SSPSTAT<4>) is set, or the bus is idle with both the S and P bits clear. When the bus is busy, enabling the SSP interrupt will generate the interrupt when the STOP condition occurs. In multi-master operation, the SDA line must be monitored, for arbitration, to see if the signal level is the expected output level. This check is performed in hardware, with the result placed in the BCLIF bit. The states where arbitration can be lost are: * * * * * Address Transfer Data Transfer A START Condition A Repeated START Condition An Acknowledge Condition SDA is a '1' and the data sampled on the SDA pin = '0', then a bus collision has taken place. The master will set the Bus Collision Interrupt Flag, BCLIF and reset the I2C port to its IDLE state (Figure 14-23). If a transmit was in progress when the bus collision occurred, the transmission is halted, the BF flag is cleared, the SDA and SCL lines are de-asserted, and the SSPBUF can be written to. When the user services the bus collision Interrupt Service Routine, and if the I2C bus is free, the user can resume communication by asserting a START condition. If a START, Repeated START, STOP, or Acknowledge condition was in progress when the bus collision occurred, the condition is aborted, the SDA and SCL lines are de-asserted, and the respective control bits in the SSPCON2 register are cleared. When the user services the bus collision Interrupt Service Routine, and if the I2C bus is free, the user can resume communication by asserting a START condition. The master will continue to monitor the SDA and SCL pins. If a STOP condition occurs, the SSPIF bit will be set. A write to the SSPBUF will start the transmission of data at the first data bit, regardless of where the transmitter left off when the bus collision occurred. In Multi-Master mode, the interrupt generation on the detection of START and STOP conditions allows the determination of when the bus is free. Control of the I2C bus can be taken when the P bit is set in the SSPSTAT register, or the bus is idle and the S and P bits are cleared.
14.4.16
MULTI -MASTER COMMUNICATION, BUS COLLISION, AND BUS ARBITRATION
Multi-Master mode support is achieved by bus arbitration. When the master outputs address/data bits onto the SDA pin, arbitration takes place when the master outputs a '1' on SDA by letting SDA float high and another master asserts a '0'. When the SCL pin floats high, data should be stable. If the expected data on
FIGURE 14-23:
BUS COLLISION TIMING FOR TRANSMIT AND ACKNOWLEDGE
Data changes while SCL = 0 SDA line pulled low by another source SDA released by master Sample SDA. While SCL is high data doesn't match what is driven by the master. Bus collision has occurred.
SDA
SCL
Set bus collision interrupt (BCLIF)
BCLIF
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PIC18CXX2
14.4.16.1 Bus Collision During a START Condition
During a START condition, a bus collision occurs if: a) b) SDA or SCL are sampled low at the beginning of the START condition (Figure 14-24). SCL is sampled low before SDA is asserted low (Figure 14-25). If the SDA pin is sampled low during this count, the BRG is reset and the SDA line is asserted early (Figure 14-26). If, however, a '1' is sampled on the SDA pin, the SDA pin is asserted low at the end of the BRG count. The baud rate generator is then reloaded and counts down to 0, and during this time, if the SCL pins are sampled as '0', a bus collision does not occur. At the end of the BRG count, the SCL pin is asserted low. Note: The reason that bus collision is not a factor during a START condition, is that no two bus masters can assert a START condition at the exact same time. Therefore, one master will always assert SDA before the other. This condition does not cause a bus collision, because the two masters must be allowed to arbitrate the first address following the START condition. If the address is the same, arbitration must be allowed to continue into the data portion, Repeated START, or STOP conditions.
During a START condition, both the SDA and the SCL pins are monitored. If the SDA pin is already low, or the SCL pin is already low, then all of the following occur: * the START condition is aborted, * the BCLIF flag is set, and * the MSSP module is reset to its IDLE state (Figure 14-24). The START condition begins with the SDA and SCL pins de-asserted. When the SDA pin is sampled high, the baud rate generator is loaded from SSPADD<6:0> and counts down to 0. If the SCL pin is sampled low while SDA is high, a bus collision occurs, because it is assumed that another master is attempting to drive a data '1' during the START condition.
FIGURE 14-24:
BUS COLLISION DURING START CONDITION (SDA ONLY)
SDA goes low before the SEN bit is set. . Set BCLIF, S bit and SSPIF set because SDA = 0, SCL = 1.
SDA
SCL Set SEN, enable START condition if SDA = 1, SCL=1 SEN SDA sampled low before START condition. Set BCLIF. S bit and SSPIF set because SDA = 0, SCL = 1. SSPIF and BCLIF are cleared in software S SEN cleared automatically because of bus collision. SSP module reset into idle state.
BCLIF
SSPIF
SSPIF and BCLIF are cleared in software
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PIC18CXX2
FIGURE 14-25: BUS COLLISION DURING START CONDITION (SCL = 0)
SDA = 0, SCL = 1
TBRG TBRG
SDA
Set SEN, enable START sequence if SDA = 1, SCL = 1 SCL = 0 before SDA = 0, Bus collision occurs, set BCLIF SCL = 0 before BRG time-out, Bus collision occurs, set BCLIF
SCL SEN
BCLIF
Interrupt cleared in software
S SSPIF
'0' '0'
'0' '0'
FIGURE 14-26:
BRG RESET DUE TO SDA ARBITRATION DURING START CONDITION
SDA = 0, SCL = 1 Set S Less than TBRG
TBRG
Set SSPIF
SDA
SDA pulled low by other master. Reset BRG and assert SDA.
SCL SEN BCLIF
S
SCL pulled low after BRG Time-out Set SEN, enable START sequence if SDA = 1, SCL = 1
'0'
S
SSPIF
SDA = 0, SCL = 1 Set SSPIF Interrupts cleared in software
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PIC18CXX2
14.4.16.2 Bus Collision During a Repeated START Condition
During a Repeated START condition, a bus collision occurs if: a) b) A low level is sampled on SDA when SCL goes from low level to high level. SCL goes low before SDA is asserted low, indicating that another master is attempting to transmit a data '1'. reloaded and begins counting. If SDA goes from high to low before the BRG times out, no bus collision occurs because no two masters can assert SDA at exactly the same time. If SCL goes from high to low before the BRG times out and SDA has not already been asserted, a bus collision occurs. In this case, another master is attempting to transmit a data '1' during the Repeated START condition, Figure 14-28. If, at the end of the BRG time-out, both SCL and SDA are still high, the SDA pin is driven low and the BRG is reloaded and begins counting. At the end of the count, regardless of the status of the SCL pin, the SCL pin is driven low and the Repeated START condition is complete.
When the user de-asserts SDA and the pin is allowed to float high, the BRG is loaded with SSPADD<6:0> and counts down to 0. The SCL pin is then de-asserted, and when sampled high, the SDA pin is sampled. If SDA is low, a bus collision has occurred (i.e., another master is attempting to transmit a data '0', Figure 14-27). If SDA is sampled high, the BRG is
FIGURE 14-27:
SDA
BUS COLLISION DURING A REPEATED START CONDITION (CASE 1)
SCL Sample SDA when SCL goes high. If SDA = 0, set BCLIF and release SDA and SCL. RSEN BCLIF Cleared in software '0' '0'
S SSPIF
FIGURE 14-28:
BUS COLLISION DURING REPEATED START CONDITION (CASE 2)
TBRG TBRG
SDA SCL SCL goes low before SDA, Set BCLIF. Release SDA and SCL. Interrupt cleared in software RSEN S SSPIF
'0'
BCLIF
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DS39026C-page 147
PIC18CXX2
14.4.16.3 Bus Collision During a STOP Condition
Bus collision occurs during a STOP condition if: a) After the SDA pin has been de-asserted and allowed to float high, SDA is sampled low after the BRG has timed out. After the SCL pin is de-asserted, SCL is sampled low before SDA goes high. The STOP condition begins with SDA asserted low. When SDA is sampled low, the SCL pin is allowed to float. When the pin is sampled high (clock arbitration), the baud rate generator is loaded with SSPADD<6:0> and counts down to 0. After the BRG times out, SDA is sampled. If SDA is sampled low, a bus collision has occurred. This is due to another master attempting to drive a data '0' (Figure 14-29). If the SCL pin is sampled low before SDA is allowed to float high, a bus collision occurs. This is another case of another master attempting to drive a data '0' (Figure 14-30).
b)
FIGURE 14-29:
BUS COLLISION DURING A STOP CONDITION (CASE 1)
TBRG TBRG TBRG
SDA sampled low after TBRG, Set BCLIF
SDA
SDA asserted low
SCL PEN BCLIF P SSPIF
'0' '0'
FIGURE 14-30:
BUS COLLISION DURING A STOP CONDITION (CASE 2)
TBRG TBRG TBRG
SDA
Assert SDA SCL goes low before SDA goes high Set BCLIF
SCL PEN BCLIF P SSPIF
'0' '0'
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PIC18CXX2
15.0 ADDRESSABLE UNIVERSAL SYNCHRONOUS ASYNCHRONOUS RECEIVER TRANSMITTER (USART)
The USART can be configured in the following modes: * Asynchronous (full duplex) * Synchronous - Master (half duplex) * Synchronous - Slave (half duplex) In order to configure pins RC6/TX/CK and RC7/RX/DT as the Universal Synchronous Asynchronous Receiver Transmitter: * bit SPEN (RCSTA<7>) must be set (= 1), and * bits TRISC<7:6> must be cleared (= 0). Register 15-1 shows the Transmit Status and Control Register (TXSTA) and Register 15-2 shows the Receive Status and Control Register (RCSTA).
The Universal Synchronous Asynchronous Receiver Transmitter (USART) module is one of the two serial I/O modules. (USART is also known as a Serial Communications Interface or SCI.) The USART can be configured as a full duplex asynchronous system that can communicate with peripheral devices, such as CRT terminals and personal computers, or it can be configured as a half-duplex synchronous system that can communicate with peripheral devices, such as A/D or D/A integrated circuits, serial EEPROMs, etc.
REGISTER 15-1:
TXSTA: TRANSMIT STATUS AND CONTROL REGISTER
R/W-0 CSRC bit 7 R/W-0 TX9 R/W-0 TXEN R/W-0 SYNC U-0 -- R/W-0 BRGH R-1 TRMT R/W-0 TX9D bit 0
bit 7
CSRC: Clock Source Select bit Asynchronous mode: Don't care Synchronous mode: 1 = Master mode (clock generated internally from BRG) 0 = Slave mode (clock from external source) TX9: 9-bit Transmit Enable bit 1 = Selects 9-bit transmission 0 = Selects 8-bit transmission TXEN: Transmit Enable bit 1 = Transmit enabled 0 = Transmit disabled Note: SREN/CREN overrides TXEN in SYNC mode.
bit 6
bit 5
bit 4
SYNC: USART Mode Select bit 1 = Synchronous mode 0 = Asynchronous mode Unimplemented: Read as '0' BRGH: High Baud Rate Select bit Asynchronous mode: 1 = High speed 0 = Low speed Synchronous mode: Unused in this mode TRMT: Transmit Shift Register Status bit 1 = TSR empty 0 = TSR full TX9D: 9th bit of transmit data. Can be Address/Data bit or a parity bit. Legend: R = Readable bit - n = Value at POR reset W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown
bit 3 bit 2
bit 1
bit 0
2001 Microchip Technology Inc.
DS39026C-page 149
PIC18CXX2
REGISTER 15-2: RCSTA: RECEIVE STATUS AND CONTROL REGISTER
R/W-0 SPEN bit 7 bit 7 R/W-0 RX9 R/W-0 SREN R/W-0 CREN R/W-0 ADDEN R-0 FERR R-0 OERR R-x RX9D bit 0
SPEN: Serial Port Enable bit 1 = Serial port enabled (configures RX/DT and TX/CK pins as serial port pins) 0 = Serial port disabled RX9: 9-bit Receive Enable bit 1 = Selects 9-bit reception 0 = Selects 8-bit reception SREN: Single Receive Enable bit Asynchronous mode: Don't care Synchronous mode - master: 1 = Enables single receive 0 = Disables single receive This bit is cleared after reception is complete. Synchronous mode - slave: Unused in this mode CREN: Continuous Receive Enable bit Asynchronous mode: 1 = Enables continuous receive 0 = Disables continuous receive Synchronous mode: 1 = Enables continuous receive until enable bit CREN is cleared (CREN overrides SREN) 0 = Disables continuous receive ADDEN: Address Detect Enable bit Asynchronous mode 9-bit (RX9 = 1): 1 = Enables address detection, enable interrupt and load of the receive buffer when RSR<8> is set 0 = Disables address detection, all bytes are received, and ninth bit can be used as parity bit FERR: Framing Error bit 1 = Framing error (can be updated by reading RCREG register and receive next valid byte) 0 = No framing error OERR: Overrun Error bit 1 = Overrun error (can be cleared by clearing bit CREN) 0 = No overrun error RX9D: 9th bit of received data, can be Address/Data bit or a parity bit. Legend: R = Readable bit - n = Value at POR reset W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown
bit 6
bit 5
bit 4
bit 3
bit 2
bit 1
bit 0
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2001 Microchip Technology Inc.
PIC18CXX2
15.1 USART Baud Rate Generator (BRG)
Example 15-1 shows the calculation of the baud rate error for the following conditions: * * * * FOSC = 16 MHz Desired Baud Rate = 9600 BRGH = 0 SYNC = 0
The BRG supports both the Asynchronous and Synchronous modes of the USART. It is a dedicated 8-bit baud rate generator. The SPBRG register controls the period of a free running 8-bit timer. In Asynchronous mode, bit BRGH (TXSTA<2>) also controls the baud rate. In Synchronous mode, bit BRGH is ignored. Table 15-1 shows the formula for computation of the baud rate for different USART modes, which only apply in Master mode (internal clock). Given the desired baud rate and FOSC, the nearest integer value for the SPBRG register can be calculated using the formula in Table 15-1. From this, the error in baud rate can be determined.
It may be advantageous to use the high baud rate (BRGH = 1), even for slower baud clocks. This is because the FOSC/(16(X + 1)) equation can reduce the baud rate error in some cases. Writing a new value to the SPBRG register causes the BRG timer to be reset (or cleared). This ensures the BRG does not wait for a timer overflow before outputting the new baud rate.
15.1.1
SAMPLING
The data on the RC7/RX/DT pin is sampled three times by a majority detect circuit to determine if a high or a low level is present at the RX pin.
EXAMPLE 15-1:
Desired Baud Rate Solving for X: X X X Calculated Baud Rate Error
CALCULATING BAUD RATE ERROR
= = = = = = = = = FOSC / (64 (X + 1)) ( (FOSC / Desired Baud rate) / 64 ) - 1 ((16000000 / 9600) / 64) - 1 [25.042] = 25 16000000 / (64 (25 + 1)) 9615 (Calculated Baud Rate - Desired Baud Rate) Desired Baud Rate (9615 - 9600) / 9600 0.16%
TABLE 15-1:
SYNC
BAUD RATE FORMULA
BRGH = 0 (Low Speed) BRGH = 1 (High Speed) Baud Rate = FOSC/(16(X+1)) NA
0 (Asynchronous) Baud Rate = FOSC/(64(X+1)) (Synchronous) Baud Rate = FOSC/(4(X+1)) 1 Legend: X = value in SPBRG (0 to 255)
TABLE 15-2:
Name TXSTA RCSTA SPBRG
REGISTERS ASSOCIATED WITH BAUD RATE GENERATOR
Bit 6 TX9 RX9 Bit 5 TXEN SREN Bit 4 SYNC CREN Bit 3 -- ADDEN Bit 2 BRGH FERR Bit 1 TRMT OERR Bit 0 TX9D RX9D Value on POR, BOR 0000 -010 0000 -00x 0000 0000 Value on all other RESETS 0000 -010 0000 -00x 0000 0000
Bit 7 CSRC SPEN
Baud Rate Generator Register
Legend: x = unknown, - = unimplemented, read as '0'. Shaded cells are not used by the BRG.
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PIC18CXX2
TABLE 15-3:
BAUD RATE (K)
BAUD RATES FOR SYNCHRONOUS MODE
FOSC = 40 MHz FOSC = 20 MHz % Error -- -- -- -- +1.73 +0.16 +0.16 -1.96 0 -- -- FOSC = 16 MHz % Error -- -- -- -- +0.16 +0.16 -0.79 +2.56 0 -- -- FOSC = 10 MHz % Error -- -- -- +1.73 +0.16 -1.36 +0.16 +4.17 0 -- -- SPBRG value (decimal) -- -- -- 255 129 32 25 7 4 0 255
Actual Rate (K) NA NA NA NA NA 76.92 96.15 303.03 500.00 39.06 10000.00
% Error -- -- -- -- -- 0 0 -0.01 0 -- --
SPBRG Actua value l Rate (decimal) (K) -- -- -- -- -- 129 103 32 19 255 0 NA NA NA NA 19.53 76.92 96.15 294.1 500 5000 19.53
SPBRG Actual value Rate (decimal) (K) -- -- -- -- 255 64 51 16 9 0 255 NA NA NA NA 19.23 76.92 95.24 307.69 500 4000 15.625
SPBRG Actual value Rate (decimal) (K) -- -- -- -- 207 51 41 12 7 0 255 NA NA NA 9.766 19.23 75.76 96.15 312.5 500 2500 9.766
0.3 1.2 2.4 9.6 19.2 76.8 96 300 500 HIGH LOW
FOSC = 7.15909 MHz BAUD RATE (K) Actual Rate (K) NA NA NA 9.622 19.24 77.82 94.20 298.3 NA 1789.8 6.991 % Error -- -- -- +0.23 +0.23 +1.32 -1.88 -0.57 -- -- -- FOSC = 1 MHz BAUD RATE (K) 0.3 1.2 2.4 9.6 19.2 76.8 96 300 500 HIGH LOW Actual Rate (K) NA 1.202 2.404 9.615 19.24 83.34 NA NA NA 250 0.9766 % Error -- +0.16 +0.16 +0.16 +0.16 +8.51 -- -- -- -- --
FOSC = 5.0688 MHz % Error -- -- -- 0 0 +3.13 +1.54 +5.60 -- -- -- SPBRG Actual value Rate (decimal) (K) -- -- -- 131 65 15 12 3 -- 0 255 NA NA NA 9.615 19.231 76.923 1000 NA NA 100 3.906
FOSC = 4 MHz % Error -- -- -- +0.16 +0.16 +0.16 +4.17 -- -- -- --
FOSC = 3.579545 MHz % Error -- -- -- +0.23 -0.83 -2.90 +3.57 -0.57 -- -- -- SPBRG value (decimal) -- -- -- 92 46 11 8 2 -- 0 255
SPBRG Actual value Rate (decimal) (K) -- -- -- 185 92 22 18 5 -- 0 255 NA NA NA 9.6 19.2 79.2 97.48 316.8 NA 1267 4.950
SPBRG Actual value Rate (decimal) (K) ---- -- -- 103 51 12 9 -- -- 0 255 NA NA NA 9.622 19.04 74.57 99.43 298.3 NA 894.9 3.496
0.3 1.2 2.4 9.6 19.2 76.8 96 300 500 HIGH LOW
FOSC = 32.768 kHz % Error +1.14 -2.48 -- -- -- -- -- -- -- -- -- SPBRG value (decimal) 26 6 -- -- -- -- -- -- -- 0 255
SPBRG Actual value Rate (decimal) (K) -- 207 103 25 12 2 -- -- -- 0 255 0.303 1.170 NA NA NA NA NA NA NA 8.192 0.032
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PIC18CXX2
TABLE 15-4:
BAUD RATE (K)
BAUD RATES FOR ASYNCHRONOUS MODE (BRGH = 0)
FOSC = 40 MHz FOSC = 20 MHz % Error -- +1.73 +0.16 -1.36 +1.73 +1.73 +8.51 +4.17 -- -- -- FOSC = 16 MHz % Error -- +0.16 +0.16 +0.16 +0.16 +8.51 -- -- -- -- -- FOSC = 4 MHz % Error -0.17 +1.67 +1.67 -- -- -- -- -- -- -- -- FOSC = 10 MHz % Error -- +0.16 +0.16 +1.73 +1.73 +1.73 -- -- -- -- -- SPBRG value (decimal) -- 129 64 15 7 1 -- -- -- 0 255
Actual Rate (K) NA NA 2.44 9.62 18.94 78.13 89.29 312.50 625.00 2.44 625.00
% Error -- -- -1.70 -0.16 +1.38 -1.70 +7.52 -4.00 -20.00 -- --
SPBRG Actual value Rate (decimal) (K) -- -- 255 64 32 7 6 1 0 255 0 NA 1.221 2.404 9.469 19.53 78.13 104.2 312.5 NA 312.5 1.221
SPBRG Actual value Rate (decimal) (K) -- 255 129 32 15 3 2 0 -- 0 255 NA 1.202 2.404 9.615 19.23 83.33 NA NA NA 250 0.977
SPBRG Actual value Rate (decimal) (K) -- 207 103 25 12 2 -- -- -- 0 255 NA 1.202 2.404 9.766 19.53 78.13 NA NA NA 156.3 0.6104
0.3 1.2 2.4 9.6 19.2 76.8 96 300 500 HIGH LOW
FOSC = 7.15909 MHz BAUD RATE (K) Actual Rate (K) NA 1.203 2.380 9.322 18.64 NA NA NA NA 111.9 0.437 % Error -- +0.23 -0.83 -2.90 -2.90 -- -- -- -- -- -- FOSC = 1 MHz BAUD RATE (K) 0.3 1.2 2.4 9.6 19.2 76.8 96 300 500 HIGH LOW Actual Rate (K) 0.300 1.202 2.232 NA NA NA NA NA NA 15.63 0.0610 % Error +0.16 +0.16 -6.99 -- -- -- -- -- -- -- --
FOSC = 5.0688 MHz % Error +3.13 0 0 +3.13 +3.13 +3.13 -- -- -- -- -- SPBRG Actual value Rate (decimal) (K) 255 65 32 7 3 0 -- -- -- 0 255 0.3005 1.202 2.404 NA NA NA NA NA NA 62.500 3.906
FOSC = 3.579545 MHz % Error +0.23 -0.83 +1.32 -2.90 -2.90 -- -- -- -- -- -- SPBRG value (decimal) 185 46 22 5 2 -- -- -- -- 0 255
SPBRG Actual value Rate (decimal) (K) -- 92 46 11 5 -- -- -- -- 0 255 0.31 1.2 2.4 9.9 19.8 79.2 NA NA NA 79.2 0.3094
SPBRG Actual value Rate (decimal) (K) 207 51 25 -- -- -- -- -- -- 0 255 0.301 1.190 2.432 9.322 18.64 NA NA NA NA 55.93 0.2185
0.3 1.2 2.4 9.6 19.2 76.8 96 300 500 HIGH LOW
FOSC = 32.768 kHz % Error -14.67 -- -- -- -- -- -- -- -- -- -- SPBRG value (decimal) 1 -- -- -- -- -- -- -- -- 0 255
SPBRG Actual value Rate (decimal) (K) 51 12 6 -- -- -- -- -- -- 0 255 0.256 NA NA NA NA NA NA NA NA 0.512 0.0020
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PIC18CXX2
TABLE 15-5:
BAUD RATE (K)
BAUD RATES FOR ASYNCHRONOUS MODE (BRGH = 1)
FOSC = 40 MHz FOSC = 20 MHz % Error +0.16 +0.16 -1.36 -1.36 -1.36 0 0 0 FOSC = 16 MHz % Error +0.16 +0.16 +0.16 +2.12 -3.55 0 -- -- FOSC = 4 MHz % Error -- +0.17 +0.13 +0.16 +0.16 -- -- -- FOSC = 10 MHz % Error +0.16 -1.36 +1.7 -1.36 +8.51 -- 0 -- SPBRG value (decimal) 64 32 15 10 4 -- 0 --
Actual Rate (K) 9.77 19.23 38.46 58.14 113.64 250.00 625.00 1250.00
% Error -1.70 -0.16 -0.16 -0.93 +1.38 0 0 0
SPBRG Actual value Rate (decimal) (K) 255 129 64 42 21 9 3 1 9.615 19.230 37.878 56.818 113.63 250 625 1250
SPBRG Actual value Rate (decimal) (K) 129 64 32 21 10 4 1 0 9.615 19.230 38.461 58.823 111.11 250 NA NA
SPBRG Actual value Rate (decimal) (K) 103 51 25 16 8 3 -- -- 9.615 18.939 39.062 56.818 125 NA 625 NA
9.6 19.2 38.4 57.6 115.2 250 625 1250
FOSC = 7.16MHz BAUD RATE (K) Actual Rate (K) 9.520 19.454 37.286 55.930 111.860 NA NA NA % Error -0.83 +1.32 -2.90 -2.90 -2.90 -- -- -- FOSC = 1 MHz BAUD RATE (K) 9.6 19.2 38.4 57.6 115.2 250 625 1250 Actual Rate (K) 8.928 20.833 31.25 62.5 NA NA NA NA % Error -6.99 +8.51 -18.61 +8.51 -- -- -- --
FOSC = 5.068 MHz % Error 0 -2.94 +3.12 -8.33 -8.33 -- -- -- SPBRG Actual value Rate (decimal) (K) 32 16 7 5 2 -- -- -- NA 1.202 2.403 9.615 19.231 NA NA NA
FOSC = 3.579545 MHz % Error +1.32 -2.90 -2.90 -2.90 -2.90 -10.51 -- -- SPBRG value (decimal) 22 11 5 3 1 0 -- --
SPBRG Actual value Rate (decimal) (K) 46 22 11 7 3 -- -- -- 9.6 18.645 39.6 52.8 105.6 NA NA NA
SPBRG Actual value Rate (decimal) (K) -- 207 103 25 12 -- -- -- 9.727 18.643 37.286 55.930 111.86 223.72 NA NA
9.6 19.2 38.4 57.6 115.2 250 625 1250
FOSC = 32.768 kHz % Error -- -- -- -- -- -- -- -- SPBRG value (decimal) -- -- -- -- -- -- -- --
SPBRG Actual value Rate (decimal) (K) 6 2 1 0 -- -- -- -- NA NA NA NA NA NA NA NA
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2001 Microchip Technology Inc.
PIC18CXX2
15.2 USART Asynchronous Mode
In this mode, the USART uses standard non-return-tozero (NRZ) format (one START bit, eight or nine data bits and one STOP bit). The most common data format is 8-bits. An on-chip dedicated 8-bit baud rate generator can be used to derive standard baud rate frequencies from the oscillator. The USART transmits and receives the LSb first. The USART's transmitter and receiver are functionally independent, but use the same data format and baud rate. The baud rate generator produces a clock, either x16 or x64 of the bit shift rate, depending on bit BRGH (TXSTA<2>). Parity is not supported by the hardware, but can be implemented in software (and stored as the ninth data bit). Asynchronous mode is stopped during SLEEP. Asynchronous mode is selected by clearing bit SYNC (TXSTA<4>). The USART Asynchronous module consists of the following important elements: * * * * Baud Rate Generator Sampling Circuit Asynchronous Transmitter Asynchronous Receiver 1. data from the TXREG register (if available). Once the TXREG register transfers the data to the TSR register (occurs in one TCY), the TXREG register is empty and flag bit TXIF (PIR1<4>) is set. This interrupt can be enabled/disabled by setting/clearing enable bit, TXIE ( PIE1<4>). Flag bit TXIF will be set, regardless of the state of enable bit TXIE and cannot be cleared in software. It will reset only when new data is loaded into the TXREG register. While flag bit TXIF indicated the status of the TXREG register, another bit TRMT (TXSTA<1>) shows the status of the TSR register. Status bit TRMT is a read only bit, which is set when the TSR register is empty. No interrupt logic is tied to this bit, so the user has to poll this bit in order to determine if the TSR register is empty. Note 1: The TSR register is not mapped in data memory, so it is not available to the user. 2: Flag bit TXIF is set when enable bit TXEN is set. To set up an asynchronous transmission: Initialize the SPBRG register for the appropriate baud rate. If a high speed baud rate is desired, set bit BRGH (Section 15.1). Enable the asynchronous serial port by clearing bit SYNC and setting bit SPEN. If interrupts are desired, set enable bit TXIE. If 9-bit transmission is desired, set transmit bit TX9. Can be used as address/data bit. Enable the transmission by setting bit TXEN, which will also set bit TXIF. If 9-bit transmission is selected, the ninth bit should be loaded in bit TX9D. Load data to the TXREG register (starts transmission).
2. 3. 4. 5. 6. 7.
15.2.1
USART ASYNCHRONOUS TRANSMITTER
The USART transmitter block diagram is shown in Figure 15-1. The heart of the transmitter is the transmit (serial) shift register (TSR). The shift register obtains its data from the read/write transmit buffer, TXREG. The TXREG register is loaded with data in software. The TSR register is not loaded until the STOP bit has been transmitted from the previous load. As soon as the STOP bit is transmitted, the TSR is loaded with new
FIGURE 15-1:
USART TRANSMIT BLOCK DIAGRAM
Data Bus TXIF TXREG Register 8 MSb (8) *** TSR Register LSb 0 Pin Buffer and Control RC6/TX/CK pin
TXIE
Interrupt TXEN Baud Rate CLK TRMT SPBRG Baud Rate Generator TX9 TX9D SPEN
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PIC18CXX2
FIGURE 15-2:
Write to TXREG BRG Output (shift clock) RC6/TX/CK (pin) TXIF bit (Transmit buffer reg. empty flag) Word 1
ASYNCHRONOUS TRANSMISSION
START Bit
Bit 0
Bit 1 Word 1
Bit 7/8
STOP Bit
TRMT bit (Transmit shift reg. empty flag)
Word 1 Transmit Shift Reg
FIGURE 15-3:
Write to TXREG BRG Output (shift clock) RC6/TX/CK (pin) TXIF bit (interrupt reg. flag)
ASYNCHRONOUS TRANSMISSION (BACK TO BACK)
Word 1 Word 2
START Bit
Bit 0
Bit 1 Word 1
Bit 7/8
STOP Bit
START Bit Word 2
Bit 0
TRMT bit (Transmit shift reg. empty flag) Note:
Word 1 Transmit Shift Reg.
Word 2 Transmit Shift Reg.
This timing diagram shows two consecutive transmissions.
TABLE 15-6:
Name INTCON PIR1 PIE1 IPR1 RCSTA TXREG TXSTA SPBRG Legend: Note 1:
REGISTERS ASSOCIATED WITH ASYNCHRONOUS TRANSMISSION
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on POR, BOR Value on all other RESETS
RBIF 0000 000x 0000 000u PEIE/ TMR0IE INT0IE RBIE TMR0IF INT0IF GIEL PSPIF(1) ADIF RCIF TXIF SSPIF CCP1IF TMR2IF TMR1IF 0000 0000 0000 0000 PSPIE(1) ADIE RCIE TXIE SSPIE CCP1IE TMR2IE TMR1IE 0000 0000 0000 0000 PSPIP(1) ADIP RCIP TXIP SSPIP CCP1IP TMR2IP TMR1IP 0000 0000 0000 0000 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D 0000 -00x 0000 -00x USART Transmit Register 0000 0000 0000 0000 CSRC TX9 TXEN SYNC -- BRGH TRMT TX9D 0000 -010 0000 -010 Baud Rate Generator Register 0000 0000 0000 0000 x = unknown, - = unimplemented locations read as '0'. Shaded cells are not used for Asynchronous Transmission. The PSPIF, PSPIE and PSPIP bits are reserved on the PIC18C2X2 devices. Always maintain these bits clear. GIE/GIEH
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2001 Microchip Technology Inc.
PIC18CXX2
15.2.2 USART ASYNCHRONOUS RECEIVER 15.2.3 SETTING UP 9-BIT MODE WITH ADDRESS DETECT
The receiver block diagram is shown in Figure 15-4. The data is received on the RC7/RX/DT pin and drives the data recovery block. The data recovery block is actually a high speed shifter operating at x16 times the baud rate, whereas the main receive serial shifter operates at the bit rate, or at FOSC. This mode would typically be used in RS-232 systems. To set up an Asynchronous Reception: 1. Initialize the SPBRG register for the appropriate baud rate. If a high speed baud rate is desired, set bit BRGH (Section 15.1). Enable the asynchronous serial port by clearing bit SYNC and setting bit SPEN. If interrupts are desired, set enable bit RCIE. If 9-bit reception is desired, set bit RX9. Enable the reception by setting bit CREN. Flag bit RCIF will be set when reception is complete and an interrupt will be generated if enable bit RCIE was set. Read the RCSTA register to get the ninth bit (if enabled) and determine if any error occurred during reception. Read the 8-bit received data by reading the RCREG register. If any error occurred, clear the error by clearing enable bit CREN.
This mode would typically be used in RS-485 systems. To set up an Asynchronous Reception with Address Detect Enable: Initialize the SPBRG register for the appropriate baud rate. If a high speed baud rate is required, set the BRGH bit. 2. Enable the asynchronous serial port by clearing the SYNC bit and setting the SPEN bit. 3. If interrupts are required, set the RCEN bit and select the desired priority level with the RCIP bit. 4. Set the RX9 bit to enable 9-bit reception. 5. Set the ADDEN bit to enable address detect. 6. Enable reception by setting the CREN bit. 7. The RCIF bit will be set when reception is complete. The interrupt will be acknowledged if the RCIE and GIE bits are set. 8. Read the RCSTA register to determine if any error occurred during reception, as well as read bit 9 of data (if applicable). 9. Read RCREG to determine if the device is being addressed. 10. If any error occurred, clear the CREN bit. 11. If the device has been addressed, clear the ADDEN bit to allow all received data into the receive buffer and interrupt the CPU. 1.
2. 3. 4. 5. 6.
7.
8. 9.
FIGURE 15-4:
USART RECEIVE BLOCK DIAGRAM
x64 Baud Rate CLK CREN SPBRG / 64 or / 16 OERR FERR
MSb STOP (8) 7
RSR Register *** 1
LSb 0 START
Baud Rate Generator RC7/RX/DT Pin Buffer and Control Data Recovery
RX9
SPEN
RX9D
RCREG Register FIFO
8 Interrupt RCIF RCIE Data Bus
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DS39026C-page 157
PIC18CXX2
FIGURE 15-5:
RX (pin) Rcv shift reg Rcv buffer reg Read Rcv buffer reg RCREG RCIF (interrupt flag) OERR bit CREN Note: This timing diagram shows three words appearing on the RX input. The RCREG (receive buffer) is read after the third word, causing the OERR (overrun) bit to be set.
ASYNCHRONOUS RECEPTION
START bit bit0 bit1 bit7/8 STOP bit START bit0 bit bit7/8 STOP bit START bit bit7/8 STOP bit
Word 1 RCREG
Word 2 RCREG
TABLE 15-7:
Name INTCON PIR1 PIE1 IPR1 RCSTA RCREG TXSTA SPBRG
REGISTERS ASSOCIATED WITH ASYNCHRONOUS RECEPTION
Bit 7 Bit 6 PEIE/ GIEL ADIF ADIE ADIP RX9 TX9 Bit 5 Bit 4 Bit 3 RBIE Bit 2 Bit 1 Bit 0 RBIF Value on POR, BOR 0000 000x Value on all other RESETS 0000 000u 0000 0000 0000 0000 0000 0000 0000 -00x 0000 0000 0000 -010
GIE/GIEH PSPIF(1) PSPIE(1) PSPIP(1) SPEN CSRC
TMR0IE INT0IE RCIF RCIE RCIP SREN TXEN
TMR0IF INT0IF CCP1IF CCP1IE CCP1IP FERR BRGH
TXIF SSPIF TXIE SSPIE TXIP SSPIP CREN ADDEN SYNC --
TMR2IF TMR1IF 0000 0000 TMR2IE TMR1IE 0000 0000 TMR2IP TMR1IP 0000 0000 OERR RX9D 0000 -00x 0000 0000 TRMT TX9D 0000 -010
USART Receive Register
Baud Rate Generator Register 0000 0000 0000 0000 Legend: x = unknown, - = unimplemented locations read as '0'. Shaded cells are not used for Asynchronous Reception. Note 1: The PSPIF, PSPIE and PSPIP bits are reserved on the PIC18C2X2 devices. Always maintain these bits clear.
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2001 Microchip Technology Inc.
PIC18CXX2
15.3 USART Synchronous Master Mode
rupt bit TXIF (PIR1<4>) is set. The interrupt can be enabled/disabled by setting/clearing enable bit TXIE (PIE1<4>). Flag bit TXIF will be set, regardless of the state of enable bit TXIE, and cannot be cleared in software. It will reset only when new data is loaded into the TXREG register. While flag bit TXIF indicates the status of the TXREG register, another bit TRMT (TXSTA<1>) shows the status of the TSR register. TRMT is a read only bit, which is set when the TSR is empty. No interrupt logic is tied to this bit, so the user has to poll this bit in order to determine if the TSR register is empty. The TSR is not mapped in data memory, so it is not available to the user. To set up a Synchronous Master Transmission: 1. 2. 3. 4. 5. 6. 7. Initialize the SPBRG register for the appropriate baud rate (Section 15.1). Enable the synchronous master serial port by setting bits SYNC, SPEN, and CSRC. If interrupts are desired, set enable bit TXIE. If 9-bit transmission is desired, set bit TX9. Enable the transmission by setting bit TXEN. If 9-bit transmission is selected, the ninth bit should be loaded in bit TX9D. Start transmission by loading data to the TXREG register.
In Synchronous Master mode, the data is transmitted in a half-duplex manner, (i.e., transmission and reception do not occur at the same time). When transmitting data, the reception is inhibited and vice versa. Synchronous mode is entered by setting bit SYNC (TXSTA<4>). In addition, enable bit SPEN (RCSTA<7>) is set in order to configure the RC6/TX/CK and RC7/RX/DT I/O pins to CK (clock) and DT (data) lines, respectively. The Master mode indicates that the processor transmits the master clock on the CK line. The Master mode is entered by setting bit CSRC (TXSTA<7>).
15.3.1
USART SYNCHRONOUS MASTER TRANSMISSION
The USART transmitter block diagram is shown in Figure 15-1. The heart of the transmitter is the transmit (serial) shift register (TSR). The shift register obtains its data from the read/write transmit buffer register TXREG. The TXREG register is loaded with data in software. The TSR register is not loaded until the last bit has been transmitted from the previous load. As soon as the last bit is transmitted, the TSR is loaded with new data from the TXREG (if available). Once the TXREG register transfers the data to the TSR register (occurs in one TCYCLE), the TXREG is empty and inter-
TABLE 15-8:
Name Bit 7
REGISTERS ASSOCIATED WITH SYNCHRONOUS MASTER TRANSMISSION
Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on POR, BOR Value on all other RESETS
INTCON PIR1 PIE1 IPR1 RCSTA TXREG TXSTA SPBRG Legend: Note 1:
GIE/ PEIE/ TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF 0000 000x 0000 000u GIEH GIEL (1) ADIF PSPIF RCIF TXIF SSPIF CCP1IF TMR2IF TMR1IF 0000 0000 0000 0000 (1) ADIE PSPIE RCIE TXIE SSPIE CCP1IE TMR2IE TMR1IE 0000 0000 0000 0000 PSPIP(1) ADIP RCIP TXIP SSPIP CCP1IP TMR2IP TMR1IP 0000 0000 0000 0000 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D 0000 -00x 0000 -00x USART Transmit Register 0000 0000 0000 0000 CSRC TX9 TXEN SYNC -- BRGH TRMT TX9D 0000 -010 0000 -010 Baud Rate Generator Register 0000 0000 0000 0000 x = unknown, - = unimplemented, read as '0'. Shaded cells are not used for Synchronous Master Transmission. The PSPIF, PSPIE and PSPIP bits are reserved on the PIC18C2X2 devices. Always maintain these bits clear.
2001 Microchip Technology Inc.
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PIC18CXX2
FIGURE 15-6: SYNCHRONOUS TRANSMISSION
Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
RC7/RX/DT pin RC6/TX/CK pin Write to TXREG reg
Write Word 1
Bit 0
Bit 1 Word 1
Bit 2
Bit 7
Bit 0
Bit 1 Word 2
Bit 7
Write Word 2
TXIF bit (Interrupt flag) TRMT bit TRMT '1' Sync Master mode; SPBRG = '0'. Continuous transmission of two 8-bit words. '1'
TXEN bit Note:
FIGURE 15-7:
SYNCHRONOUS TRANSMISSION (THROUGH TXEN)
bit0 bit1 bit2 bit6 bit7
RC7/RX/DT pin RC6/TX/CK pin
Write to TXREG reg
TXIF bit
TRMT bit
TXEN bit
DS39026C-page 160
2001 Microchip Technology Inc.
PIC18CXX2
15.3.2 USART SYNCHRONOUS MASTER RECEPTION
Ensure bits CREN and SREN are clear. If interrupts are desired, set enable bit RCIE. If 9-bit reception is desired, set bit RX9. If a single reception is required, set bit SREN. For continuous reception, set bit CREN. 7. Interrupt flag bit RCIF will be set when reception is complete and an interrupt will be generated if the enable bit RCIE was set. 8. Read the RCSTA register to get the ninth bit (if enabled) and determine if any error occurred during reception. 9. Read the 8-bit received data by reading the RCREG register. 10. If any error occurred, clear the error by clearing bit CREN. 3. 4. 5. 6.
Once Synchronous mode is selected, reception is enabled by setting either enable bit SREN (RCSTA<5>), or enable bit CREN (RCSTA<4>). Data is sampled on the RC7/RX/DT pin on the falling edge of the clock. If enable bit SREN is set, only a single word is received. If enable bit CREN is set, the reception is continuous until CREN is cleared. If both bits are set, then CREN takes precedence. To set up a Synchronous Master Reception: 1. 2. Initialize the SPBRG register for the appropriate baud rate (Section 15.1). Enable the synchronous master serial port by setting bits SYNC, SPEN and CSRC.
TABLE 15-9:
Name
REGISTERS ASSOCIATED WITH SYNCHRONOUS MASTER RECEPTION
Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on POR, BOR Value on all other RESETS
Bit 7
INTCON PIR1 PIE1 IPR1 RCSTA RCREG TXSTA SPBRG Legend: Note 1:
GIE/ PEIE/ TMR0IE INT0IE RBIE TMR0IF INT0IF RBIF 0000 000x 0000 000u GIEH GIEL (1) PSPIF ADIF RCIF TXIF SSPIF CCP1IF TMR2IF TMR1IF 0000 0000 0000 0000 (1) PSPIE ADIE RCIE TXIE SSPIE CCP1IE TMR2IE TMR1IE 0000 0000 0000 0000 PSPIP(1) ADIP RCIP TXIP SSPIP CCP1IP TMR2IP TMR1IP 0000 0000 0000 0000 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D 0000 -00x 0000 -00x USART Receive Register 0000 0000 0000 0000 CSRC TX9 TXEN SYNC -- BRGH TRMT TX9D 0000 -010 0000 -010 Baud Rate Generator Register 0000 0000 0000 0000 x = unknown, - = unimplemented, read as '0'. Shaded cells are not used for Synchronous Master Reception. The PSPIF, PSPIE and PSPIP bits are reserved on the PIC18C2X2 devices. Always maintain these bits clear.
FIGURE 15-8:
SYNCHRONOUS RECEPTION (MASTER MODE, SREN)
Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
RC7/RX/DT pin RC6/TX/CK pin Write to bit SREN SREN bit CREN bit RCIF bit '0'
bit0
bit1
bit2
bit3
bit4
bit5
bit6
bit7
'0'
(interrupt)
Read RXREG Note: Timing diagram demonstrates Sync Master mode with bit SREN = '1' and bit BRGH = '0'.
2001 Microchip Technology Inc.
DS39026C-page 161
PIC18CXX2
15.4 USART Synchronous Slave Mode
To set up a Synchronous Slave Transmission: 1. Enable the synchronous slave serial port by setting bits SYNC and SPEN and clearing bit CSRC. Clear bits CREN and SREN. If interrupts are desired, set enable bit TXIE. If 9-bit transmission is desired, set bit TX9. Enable the transmission by setting enable bit TXEN. If 9-bit transmission is selected, the ninth bit should be loaded in bit TX9D. Start transmission by loading data to the TXREG register. Synchronous Slave mode differs from the Master mode in the fact that the shift clock is supplied externally at the RC6/TX/CK pin (instead of being supplied internally in Master mode). This allows the device to transfer or receive data while in SLEEP mode. Slave mode is entered by clearing bit CSRC (TXSTA<7>).
15.4.1
USART SYNCHRONOUS SLAVE TRANSMIT
2. 3. 4. 5. 6. 7.
The operation of the Synchronous Master and Slave modes are identical, except in the case of the SLEEP mode. If two words are written to the TXREG and then the SLEEP instruction is executed, the following will occur: a) b) c) d) The first word will immediately transfer to the TSR register and transmit. The second word will remain in TXREG register. Flag bit TXIF will not be set. When the first word has been shifted out of TSR, the TXREG register will transfer the second word to the TSR and flag bit TXIF will now be set. If enable bit TXIE is set, the interrupt will wake the chip from SLEEP. If the global interrupt is enabled, the program will branch to the interrupt vector.
e)
TABLE 15-10: REGISTERS ASSOCIATED WITH SYNCHRONOUS SLAVE TRANSMISSION
Name INTCON PIR1 PIE1 IPR1 RCSTA TXREG TXSTA SPBRG Legend: Note 1: Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on POR, BOR Value on all other RESETS
RBIF 0000 000x 0000 000u GIE/ PEIE/ TMR0IE INT0IE RBIE TMR0IF INT0IF GIEH GIEL PSPIF(1) ADIF RCIF TXIF SSPIF CCP1IF TMR2IF TMR1IF 0000 0000 0000 0000 PSPIE(1) ADIE RCIE TXIE SSPIE CCP1IE TMR2IE TMR1IE 0000 0000 0000 0000 PSPIP(1) ADIP RCIP TXIP SSPIP CCP1IP TMR2IP TMR1IP 0000 0000 0000 0000 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D 0000 -00x 0000 -00x USART Transmit Register 0000 0000 0000 0000 CSRC TX9 TXEN SYNC -- BRGH TRMT TX9D 0000 -010 0000 -010 Baud Rate Generator Register 0000 0000 0000 0000 x = unknown, - = unimplemented, read as '0'. Shaded cells are not used for Synchronous Slave Transmission. The PSPIF, PSPIE and PSPIP bits are reserved on the PIC18C2X2 devices. Always maintain these bits clear.
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2001 Microchip Technology Inc.
PIC18CXX2
15.4.2 USART SYNCHRONOUS SLAVE RECEPTION
To set up a Synchronous Slave Reception: 1. Enable the synchronous master serial port by setting bits SYNC and SPEN and clearing bit CSRC. If interrupts are desired, set enable bit RCIE. If 9-bit reception is desired, set bit RX9. To enable reception, set enable bit CREN. Flag bit RCIF will be set when reception is complete. An interrupt will be generated if enable bit RCIE was set. Read the RCSTA register to get the ninth bit (if enabled) and determine if any error occurred during reception. Read the 8-bit received data by reading the RCREG register. If any error occurred, clear the error by clearing bit CREN.
The operation of the Synchronous Master and Slave modes is identical, except in the case of the SLEEP mode and bit SREN, which is a "don't care" in Slave mode. If receive is enabled by setting bit CREN prior to the SLEEP instruction, then a word may be received during SLEEP. On completely receiving the word, the RSR register will transfer the data to the RCREG register, and if enable bit RCIE bit is set, the interrupt generated will wake the chip from SLEEP. If the global interrupt is enabled, the program will branch to the interrupt vector.
2. 3. 4. 5.
6.
7. 8.
TABLE 15-11: REGISTERS ASSOCIATED WITH SYNCHRONOUS SLAVE RECEPTION
Name INTCON PIR1 PIE1 IPR1 RCSTA RCREG TXSTA SPBRG Legend: Note 1: Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on POR, BOR Value on all other RESETS
RBIF 0000 000x 0000 000u GIE/ PEIE/ TMR0IE INT0IE RBIE TMR0IF INT0IF GIEH GIEL PSPIF(1) ADIF RCIF TXIF SSPIF CCP1IF TMR2IF TMR1IF 0000 0000 0000 0000 PSPIE(1) ADIE RCIE TXIE SSPIE CCP1IE TMR2IE TMR1IE 0000 0000 0000 0000 PSPIP(1) ADIP RCIP TXIP SSPIP CCP1IP TMR2IP TMR1IP 0000 0000 0000 0000 SPEN RX9 SREN CREN ADDEN FERR OERR RX9D 0000 -00x 0000 -00x USART Receive Register 0000 0000 0000 0000 CSRC TX9 TXEN SYNC -- BRGH TRMT TX9D 0000 -010 0000 -010 Baud Rate Generator Register 0000 0000 0000 0000 x = unknown, - = unimplemented, read as '0'. Shaded cells are not used for Synchronous Slave Reception. The PSPIF, PSPIE and PSPIP bits are reserved on the PIC18C2X2 devices. Always maintain these bits clear.
2001 Microchip Technology Inc.
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PIC18CXX2
NOTES:
DS39026C-page 164
2001 Microchip Technology Inc.
PIC18CXX2
16.0 COMPATIBLE 10-BIT ANALOGTO-DIGITAL CONVERTER (A/D) MODULE
The A/D module has four registers. These registers are: * * * * A/D Result High Register (ADRESH) A/D Result Low Register (ADRESL) A/D Control Register 0 (ADCON0) A/D Control Register 1 (ADCON1)
The analog-to-digital (A/D) converter module has five inputs for the PIC18C2x2 devices and eight for the PIC18C4x2 devices. This module has the ADCON0 and ADCON1 register definitions that are compatible with the mid-range A/D module. The A/D allows conversion of an analog input signal to a corresponding 10-bit digital number.
The ADCON0 register, shown in Register 16-1, controls the operation of the A/D module. The ADCON1 register, shown in Register 16-2, configures the functions of the port pins.
REGISTER 16-1:
ADCON0 REGISTER
R/W-0 ADCS1 bit 7 R/W-0 ADCS0 R/W-0 CHS2 R/W-0 CHS1 R/W-0 CHS0 R/W-0 GO/DONE U-0 -- R/W-0 ADON bit 0
bit 7-6
ADCS1:ADCS0: A/D Conversion Clock Select bits (ADCON0 bits in bold) ADCON1
0 0 0 0 1 1 1 1
ADCON0
00 01 10 11 00 01 10 11
Clock Conversion FOSC/2 FOSC/8 FOSC/32 FRC (clock derived from the internal A/D RC oscillator) FOSC/4 FOSC/16 FOSC/64 FRC (clock derived from the internal A/D RC oscillator)
bit 5-3
CHS2:CHS0: Analog Channel Select bits 000 = channel 0 (AN0) 001 = channel 1 (AN1) 010 = channel 2 (AN2) 011 = channel 3 (AN3) 100 = channel 4 (AN4) 101 = channel 5 (AN5) 110 = channel 6 (AN6) 111 = channel 7 (AN7) Note: The PIC18C2X2 devices do not implement the full 8 A/D channels; the unimplemented selections are reserved. Do not select any unimplemented channel.
bit 2
GO/DONE: A/D Conversion Status bit When ADON = 1: 1 = A/D conversion in progress (setting this bit starts the A/D conversion which is automatically cleared by hardware when the A/D conversion is complete) 0 = A/D conversion not in progress Unimplemented: Read as '0' ADON: A/D On bit 1 = A/D converter module is powered up 0 = A/D converter module is shut-off and consumes no operating current Legend: R = Readable bit - n = Value at POR reset W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown
bit 1 bit 0
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REGISTER 16-2: ADCON1 REGISTER
R/W-0 ADFM bit 7 bit 7 ADFM: A/D Result Format Select bit 1 = Right justified. Six (6) Most Significant bits of ADRESH are read as '0'. 0 = Left justified. Six (6) Least Significant bits of ADRESL are read as '0'. ADCS2: A/D Conversion Clock Select bit (ADCON1 bits in bold) ADCON1 ADCON0 0 0 0 0 1 1 1 1 00 01 10 11 00 01 10 11 Clock Conversion FOSC/2 FOSC/8 FOSC/32 FRC (clock derived from the internal A/D RC oscillator) FOSC/4 FOSC/16 FOSC/64 FRC (clock derived from the internal A/D RC oscillator) R/W-0 ADCS2 U-0 -- U-0 -- R/W-0 PCFG3 R/W-0 PCFG2 R/W-0 PCFG1 R/W-0 PCFG0 bit 0
bit 6
bit 5-4 bit 3-0
Unimplemented: Read as '0' PCFG3:PCFG0: A/D Port Configuration Control bits PCFG 0000 0001 0010 0011 0100 0101 011x 1000 1001 1010 1011 1100 1101 1110 1111 AN7 A A D D D D D A D D D D D D D AN6 A A D D D D D A D D D D D D D AN5 A A D D D D D A A A A D D D D AN4 A A A A D D D A A A A A D D D AN3 A VREF+ A VREF+ A VREF+ D VREF+ A VREF+ VREF+ VREF+ VREF+ D VREF+ AN2 A A A A D D D VREFA A VREFVREFVREFD VREFAN1 A A A A A A D A A A A A A D D AN0 A A A A A A D A A A A A A A A VREF+ VDD AN3 VDD AN3 VDD AN3 -- AN3 VDD AN3 AN3 AN3 AN3 VDD AN3 VREFVSS VSS VSS VSS VSS VSS -- AN2 VSS VSS AN2 AN2 AN2 VSS AN2 C/R 8/0 7/1 5/0 4/1 3/0 2/1 0/0 6/2 6/0 5/1 4/2 3/2 2/2 1/0 1/2
A = Analog input D = Digital I/O C/R = # of analog input channels/# of A/D voltage references Legend: R = Readable bit - n = Value at POR reset Note: W = Writable bit '1' = Bit is set U = Unimplemented bit, read as `0' '0' = Bit is cleared x = Bit is unknown
On any device RESET, the port pins that are multiplexed with analog functions (ANx) are forced to be an analog input.
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The analog reference voltage is software selectable to either the device's positive and negative supply voltage (VDD and VSS) or the voltage level on the RA3/AN3/ VREF+ pin and RA2/AN2/VREF-. The A/D converter has a unique feature of being able to operate while the device is in SLEEP mode. To operate in SLEEP, the A/D conversion clock must be derived from the A/D's internal RC oscillator. The output of the sample and hold is the input into the converter, which generates the result via successive approximation. A device RESET forces all registers to their RESET state. This forces the A/D module to be turned off and any conversion is aborted. Each port pin associated with the A/D converter can be configured as an analog input (RA3 can also be a voltage reference) or as a digital I/O. The ADRESH and ADRESL registers contain the result of the A/D conversion. When the A/D conversion is complete, the result is loaded into the ADRESH/ ADRESL registers, the GO/DONE bit (ADCON0<2>) is cleared, and A/D interrupt flag bit ADIF is set. The block diagram of the A/D module is shown in Figure 16-1.
FIGURE 16-1:
A/D BLOCK DIAGRAM
CHS2:CHS0
111 110 101 100 VAIN (Input Voltage) 10-bit Converter A/D PCFG0 VDD VREF+ Reference voltage VREFVSS 011 010 001 000
AN7 AN6 AN5 AN4 AN3 AN2 AN1 AN0
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The value that is in the ADRESH/ADRESL registers is not modified for a Power-on Reset. The ADRESH/ ADRESL registers will contain unknown data after a Power-on Reset. After the A/D module has been configured as desired, the selected channel must be acquired before the conversion is started. The analog input channels must have their corresponding TRIS bits selected as an input. To determine acquisition time, see Section 16.1. After this acquisition time has elapsed, the A/D conversion can be started. The following steps should be followed for doing an A/D conversion: 1. Configure the A/D module: * Configure analog pins, voltage reference and digital I/O (ADCON1) * Select A/D input channel (ADCON0) * Select A/D conversion clock (ADCON0) * Turn on A/D module (ADCON0) Configure A/D interrupt (if desired): * Clear ADIF bit * Set ADIE bit * Set GIE bit Wait the required acquisition time. Start conversion: * Set GO/DONE bit (ADCON0) Wait for A/D conversion to complete, by either: * Polling for the GO/DONE bit to be cleared OR 6. 7. * Waiting for the A/D interrupt Read A/D Result registers (ADRESH/ADRESL); clear bit ADIF if required. For next conversion, go to step 1 or step 2, as required. The A/D conversion time per bit is defined as TAD. A minimum wait of 2TAD is required before next acquisition starts.
16.1
A/D Acquisition Requirements
For the A/D converter to meet its specified accuracy, the charge holding capacitor (CHOLD) must be allowed to fully charge to the input channel voltage level. The analog input model is shown in Figure 16-2. The source impedance (RS) and the internal sampling switch (RSS) impedance directly affect the time required to charge the capacitor CHOLD. The sampling switch (RSS) impedance varies over the device voltage (VDD). The source impedance affects the offset voltage at the analog input (due to pin leakage current). The maximum recommended impedance for analog sources is 2.5 k. After the analog input channel is selected (changed), this acquisition must be done before the conversion can be started. Note: When the conversion is started, the holding capacitor is disconnected from the input pin.
2.
3. 4. 5.
FIGURE 16-2:
ANALOG INPUT MODEL
VDD VT = 0.6V Sampling Switch RIC 1k SS RSS
Rs
ANx
VAIN
CPIN 5 pF VT = 0.6V
I leakage 500 nA
CHOLD = 120 pF
VSS
Legend: CPIN = input capacitance = threshold voltage VT I LEAKAGE = leakage current at the pin due to various junctions = interconnect resistance RIC = sampling switch SS = sample/hold capacitance (from DAC) CHOLD
6V 5V VDD 4V 3V 2V
5 6 7 8 9 10 11 Sampling Switch (k)
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To calculate the minimum acquisition time, Equation 16-1 may be used. This equation assumes that 1/2 LSb error is used (1024 steps for the A/D). The 1/2 LSb error is the maximum error allowed for the A/D to meet its specified resolution.
EQUATION 16-1:
TACQ = =
ACQUISITION TIME
Amplifier Settling Time + Holding Capacitor Charging Time + Temperature Coefficient TAMP + TC + TCOFF
EQUATION 16-2:
VHOLD = or TC =
A/D MINIMUM CHARGING TIME
(VREF - (VREF/2048)) * (1 - e(-Tc/CHOLD(RIC + RSS + RS))) -(120 pF)(1 k + RSS + RS) ln(1/2047)
Example 16-1 shows the calculation of the minimum required acquisition time TACQ. This calculation is based on the following application system assumptions: * * * * * * = CHOLD Rs = Conversion Error VDD = Temperature = VHOLD = 120 pF 2.5 k 1/2 LSb 5V Rss = 7 k 50C (system max.) 0V @ time = 0
EXAMPLE 16-1:
TACQ = TACQ = TC =
CALCULATING THE MINIMUM REQUIRED ACQUISITION TIME
TAMP + TC + TCOFF 2 s + Tc + [(Temp - 25C)(0.05 s/C)] -CHOLD (RIC + RSS + RS) ln(1/2047) -120 pF (1 k + 7 k + 2.5 k) ln(0.0004885) -120 pF (10.5 k) ln(0.0004885) -1.26 s (-7.6241) 9.61 s 2 s + 9.61 s + [(50C - 25C)(0.05 s/C)] 11.61 s + 1.25 s 12.86 s
Temperature coefficient is only required for temperatures > 25C.
TACQ =
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16.2 Selecting the A/D Conversion Clock 16.3 Configuring Analog Port Pins
The ADCON1, TRISA and TRISE registers control the operation of the A/D port pins. The port pins that are desired as analog inputs must have their corresponding TRIS bits set (input). If the TRIS bit is cleared (output), the digital output level (VOH or VOL) will be converted. The A/D operation is independent of the state of the CHS2:CHS0 bits and the TRIS bits. Note 1: When reading the port register, all pins configured as analog input channels will read as cleared (a low level). Pins configured as digital inputs will convert an analog input. Analog levels on a digitally configured input will not affect the conversion accuracy. 2: Analog levels on any pin that is defined as a digital input (including the AN4:AN0 pins) may cause the input buffer to consume current that is out of the devices specification.
The A/D conversion time per bit is defined as TAD. The A/D conversion requires 12 TAD per 10-bit conversion. The source of the A/D conversion clock is software selectable. The seven possible options for TAD are: * * * * * * * 2TOSC 4TOSC 8TOSC 16TOSC 32TOSC 64TOSC Internal RC oscillator
For correct A/D conversions, the A/D conversion clock (TAD) must be selected to ensure a minimum TAD time of 1.6 s. Table 16-1 shows the resultant TAD times derived from the device operating frequencies and the A/D clock source selected.
TABLE 16-1:
TAD vs. DEVICE OPERATING FREQUENCIES
Device Frequency 40 MHz 50 ns 100 ns 200 ns 400 ns 800 ns 1.6 s 2 - 6 s(1) 20 MHz 100 ns(2) 200 ns(2) 400 ns(2) 800 ns(2) 1.6 s 3.2 s 2 - 6 s(1) 5 MHz 400 ns(2) 800 ns(2) 1.6 s 3.2 s 6.4 s 12.8 s 2 - 6 s(1) 1.25 MHz 1.6 s 3.2 s 6.4 s 12.8 s 25.6 s(3) 51.2 s(3) 2 - 6 s(1) 333.33 kHz 6 s 12 s 24 s(3) 48 s(3) 96 s(3) 192 s(3) 2 - 6 s(1)
AD Clock Source (TAD) Operation 2TOSC 4TOSC 8TOSC 16TOSC 32TOSC 64TOSC RC Legend: Note 1: 2: 3: ADCS2:ADCS0 000 100 001 101 010 110 011
Shaded cells are outside of recommended range. The RC source has a typical TAD time of 4 s. These values violate the minimum required TAD time. For faster conversion times, the selection of another clock source is recommended.
TABLE 16-2:
TAD vs. DEVICE OPERATING FREQUENCIES (FOR EXTENDED, LC, DEVICES)
Device Frequency 4 MHz 500 1.0 ns(2) s(2) 2 MHz 1.0 2.0 s(2) s(2) 1.25 MHz 1.6 3.2 s(2) s(2) 333.33 kHz 6 s 12 s 24 s(3) 48 s(3) 96 s(3) 192 s(3) 3 - 9 s(1,4)
AD Clock Source (TAD) Operation 2TOSC 4TOSC 8TOSC 16TOSC 32TOSC 64TOSC RC Legend: Note 1: 2: 3: ADCS2:ADCS0 000 100 001 101 010 110 011
2.0 s(2) 4.0 s(2) 8.0 s 16.0 s 3-9 s(1,4)
4.0 s 8.0 s 16.0 s 32.0 s 3-9 s(1,4)
6.4 s 12.8 s 25.6 3-9 s(3) 51.2 s(3) s(1,4)
Shaded cells are outside of recommended range. The RC source has a typical TAD time of 6 s. These values violate the minimum required TAD time. For faster conversion times, the selection of another clock source is recommended.
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16.4 A/D Conversions 16.5 Use of the CCP2 Trigger
Figure 16-3 shows the operation of the A/D converter after the GO bit has been set. Clearing the GO/DONE bit during a conversion will abort the current conversion. The A/D result register pair will NOT be updated with the partially completed A/D conversion sample. That is, the ADRESH:ADRESL registers will continue to contain the value of the last completed conversion (or the last value written to the ADRESH:ADRESL registers). After the A/D conversion is aborted, a 2TAD wait is required before the next acquisition is started. After this 2TAD wait, acquisition on the selected channel is automatically started. Note: The GO/DONE bit should NOT be set in the same instruction that turns on the A/D. An A/D conversion can be started by the "special event trigger" of the CCP2 module. This requires that the CCP2M3:CCP2M0 bits (CCP2CON<3:0>) be programmed as 1011 and that the A/D module is enabled (ADON bit is set). When the trigger occurs, the GO/ DONE bit will be set, starting the A/D conversion and the Timer1 (or Timer3) counter will be reset to zero. Timer1 (or Timer3) is reset to automatically repeat the A/D acquisition period with minimal software overhead (moving ADRESH/ADRESL to the desired location). The appropriate analog input channel must be selected and the minimum acquisition done before the "special event trigger" sets the GO/DONE bit (starts a conversion). If the A/D module is not enabled (ADON is cleared), the "special event trigger" will be ignored by the A/D module, but will still reset the Timer1 (or Timer3) counter.
FIGURE 16-3:
A/D CONVERSION TAD CYCLES
TCY - TAD TAD1 TAD2 TAD3 TAD4 TAD5 TAD6 TAD7 TAD8 TAD9 TAD10 TAD11 b0 b1 b3 b0 b4 b2 b5 b7 b6 b8 b9 Conversion Starts Holding capacitor is disconnected from analog input (typically 100 ns) Set GO bit Next Q4: ADRESH/ADRESL is loaded, GO bit is cleared, ADIF bit is set, holding capacitor is connected to analog input.
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TABLE 16-3:
Name
SUMMARY OF A/D REGISTERS
Bit 6 PEIE/ GIEL ADIF ADIE ADIP -- -- -- Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on POR, BOR Value on all other RESETS
Bit 7 GIE/ GIEH PSPIF(1) PSPIE(1) PSPIP(1) -- -- --
INTCON PIR1 PIE1 IPR1 PIR2 PIE2 IPR2 ADRESH ADRESL ADCON0 ADCON1 PORTA TRISA PORTE LATE TRISE
TMR0IE RCIF RCIE RCIP -- -- --
INT0IE TXIF TXIE TXIP -- -- --
RBIE SSPIF SSPIE SSPIP BCLIF BCLIE BCLIP
TMR0IF CCP1IF CCP1IE CCP1IP LVDIF LVDIE LVDIP
INT0IF TMR2IF TMR2IE TMR2IP TMR3IF TMR3IE TMR3IP
RBIF TMR1IF TMR1IE TMR1IP CCP2IF CCP2IE CCP2IP
0000 000x 0000 000u 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 0000 ---- 0000 ---- 0000 ---- 0000 ---- 0000 ---- 0000 ---- 0000 xxxx xxxx uuuu uuuu xxxx xxxx uuuu uuuu
A/D Result Register A/D Result Register ADCS1 ADFM -- -- -- -- IBF ADCS0 ADCS2 RA6 -- -- OBF CHS2 -- RA5 -- -- IBOV CHS1 -- RA4 -- -- PSPMODE CHS0 PCFG3 RA3 -- -- -- GO/ DONE PCFG2 RA2 RE2 LATE2 -- PCFG1 RA1 RE1 LATE1 ADON PCFG0 RA0 RE0 LATE0
0000 00-0 0000 00-0 ---- -000 ---- -000 --0x 0000 --0u 0000 --11 1111 --11 1111 ---- -000 ---- -000 ---- -xxx ---- -uuu 0000 -111 0000 -111
PORTA Data Direction Register
PORTE Data Direction bits
Legend: x = unknown, u = unchanged, -- = unimplemented, read as '0'. Shaded cells are not used for A/D conversion. Note 1: The PSPIF, PSPIE and PSPIP bits are reserved on the PIC18C2X2 devices. Always maintain these bits clear.
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17.0 LOW VOLTAGE DETECT
In many applications, the ability to determine if the device voltage (VDD) is below a specified voltage level is a desirable feature. A window of operation for the application can be created, where the application software can do "housekeeping tasks" before the device voltage exits the valid operating range. This can be done using the Low Voltage Detect module. This module is a software programmable circuitry, where a device voltage trip point can be specified. When the voltage of the device becomes lower then the specified point, an interrupt flag is set. If the interrupt is enabled, the program execution will branch to the interrupt vector address and the software can then respond to that interrupt source. The Low Voltage Detect circuitry is completely under software control. This allows the circuitry to be "turned off" by the software, which minimizes the current consumption for the device. Figure 17-1 shows a possible application voltage curve (typically for batteries). Over time, the device voltage decreases. When the device voltage equals voltage VA, the LVD logic generates an interrupt. This occurs at time TA. The application software then has the time, until the device voltage is no longer in valid operating range, to shut-down the system. Voltage point VB is the minimum valid operating voltage specification. This occurs at time TB. The difference TB - TA is the total time for shut-down.
FIGURE 17-1:
TYPICAL LOW VOLTAGE DETECT APPLICATION
Voltage
VA VB
Legend: VA = LVD trip point VB = Minimum valid device operating voltage TB
Time
TA
The block diagram for the LVD module is shown in Figure 17-2. A comparator uses an internally generated reference voltage as the set point. When the selected tap output of the device voltage crosses the set point (is lower than), the LVDIF bit is set. Each node in the resistor divider represents a "trip point" voltage. The "trip point" voltage is the minimum supply voltage level at which the device can operate before the LVD module asserts an interrupt. When the
supply voltage is equal to the trip point, the voltage tapped off of the resistor array is equal to the 1.2V internal reference voltage generated by the voltage reference module. The comparator then generates an interrupt signal setting the LVDIF bit. This voltage is software programmable to any one of 16 values (see Figure 17-2). The trip point is selected by programming the LVDL3:LVDL0 bits (LVDCON<3:0>).
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FIGURE 17-2: LOW VOLTAGE DETECT (LVD) BLOCK DIAGRAM
VDD LVDIN LVD Control Register
16 to 1 MUX
LVDIF
LVDEN
Internally Generated Nominal Reference Voltage 1.2V
The LVD module has an additional feature that allows the user to supply the trip voltage to the module from an external source. This mode is enabled when bits LVDL3:LVDL0 are set to 1111. In this state, the comparator input is multiplexed from the external input pin LVDIN (Figure 17-3).
This gives flexibility, because it allows a user to configure the Low Voltage Detect interrupt to occur at any voltage in the valid operating range.
FIGURE 17-3:
LOW VOLTAGE DETECT (LVD) WITH EXTERNAL INPUT BLOCK DIAGRAM
VDD VDD LVD Control Register LVDIN 16 to 1 MUX LVDEN LVD
Externally Generated Trip Point
VxEN BODEN
EN BGAP
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17.1 Control Register
The Low Voltage Detect Control register controls the operation of the Low Voltage Detect circuitry.
REGISTER 17-1:
LVDCON REGISTER
U-0 -- bit 7 U-0 -- R-0 IRVST R/W-0 LVDEN R/W-0 LVDL3 R/W-1 LVDL2 R/W-0 LVDL1 R/W-1 LVDL0 bit 0
bit 7-6 bit 5
Unimplemented: Read as '0' IRVST: Internal Reference Voltage Stable Flag bit 1 = Indicates that the Low Voltage Detect logic will generate the interrupt flag at the specified voltage range 0 = Indicates that the Low Voltage Detect logic will not generate the interrupt flag at the specified voltage range and the LVD interrupt should not be enabled LVDEN: Low Voltage Detect Power Enable bit 1 = Enables LVD, powers up LVD circuit 0 = Disables LVD, powers down LVD circuit LVDL3:LVDL0: Low Voltage Detection Limit bits 1111 = External analog input is used (input comes from the LVDIN pin) 1110 = 4.5V min. - 4.77V max. 1101 = 4.2V min. - 4.45V max. 1100 = 4.0V min. - 4.24V max. 1011 = 3.8V min. - 4.03V max. 1010 = 3.6V min. - 3.82V max. 1001 = 3.5V min. - 3.71V max. 1000 = 3.3V min. - 3.50V max. 0111 = 3.0V min. - 3.18V max. 0110 = 2.8V min. - 2.97V max. 0101 = 2.7V min. - 2.86V max. 0100 = 2.5V min. - 2.65V max. 0011 = 2.4V min. - 2.54V max. 0010 = 2.2V min. - 2.33V max. 0001 = 2.0V min. - 2.12V max. 0000 = 1.8V min. - 1.91V max. Note: LVDL3:LVDL0 modes which result in a trip point below the valid operating voltage of the device are not tested.
bit 4
bit 3-0
Legend: R = Readable bit U = Unimplemented bit, read as `0' W = Writable bit - n = Value at POR reset
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17.2 Operation
The following steps are needed to set up the LVD module: 1. Write the value to the LVDL3:LVDL0 bits (LVDCON register), which selects the desired LVD Trip Point. Ensure that LVD interrupts are disabled (the LVDIE bit is cleared, or the GIE bit is cleared). Enable the LVD module (set the LVDEN bit in the LVDCON register). Wait for the LVD module to stabilize (the IRVST bit to become set). Clear the LVD interrupt flag, which may have falsely become set until the LVD module has stabilized (clear the LVDIF bit). Enable the LVD interrupt (set the LVDIE and the GIE bits). Depending on the power source for the device voltage, the voltage normally decreases relatively slowly. This means that the LVD module does not need to be constantly operating. To decrease the current requirements, the LVD circuitry only needs to be enabled for short periods, where the voltage is checked. After doing the check, the LVD module may be disabled. Each time that the LVD module is enabled, the circuitry requires some time to stabilize. After the circuitry has stabilized, all status flags may be cleared. The module will then indicate the proper state of the system.
2. 3. 4. 5.
6.
Figure 17-4 shows typical waveforms that the LVD module may be used to detect.
FIGURE 17-4:
CASE 1:
LOW VOLTAGE DETECT WAVEFORMS
LVDIF may not be set VDD VLVD LVDIF
Enable LVD Internally Generated Reference stable 50 ms LVDIF cleared in software
CASE 2: VDD VLVD LVDIF Enable LVD Internally Generated Reference stable 50 ms
LVDIF cleared in software LVDIF cleared in software, LVDIF remains set since LVD condition still exists
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17.2.1 REFERENCE VOLTAGE SET POINT
17.3
Operation During SLEEP
The Internal Reference Voltage of the LVD module may be used by other internal circuitry (the Programmable Brown-out Reset). If these circuits are disabled (lower current consumption), the reference voltage circuit requires a time to become stable before a low voltage condition can be reliably detected. This time is invariant of system clock speed. This start-up time is specified in electrical specification parameter #36. The low voltage interrupt flag will not be enabled until a stable reference voltage is reached. Refer to the waveform in Figure 17-4.
When enabled, the LVD circuitry continues to operate during SLEEP. If the device voltage crosses the trip point, the LVDIF bit will be set and the device will wakeup from SLEEP. Device execution will continue from the interrupt vector address, if interrupts have been globally enabled.
17.4
Effects of a RESET
A device RESET forces all registers to their RESET state. This forces the LVD module to be turned off.
17.2.2
CURRENT CONSUMPTION
When the module is enabled, the LVD comparator and voltage divider are enabled and will consume static current. The voltage divider can be tapped from multiple places in the resistor array. Total current consumption, when enabled, is specified in electrical specification parameter #D022B.
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NOTES:
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18.0 SPECIAL FEATURES OF THE CPU
SLEEP mode is designed to offer a very low current Power-down mode. The user can wake-up from SLEEP through external RESET, Watchdog Timer Wake-up or through an interrupt. Several oscillator options are also made available to allow the part to fit the application. The RC oscillator option saves system cost, while the LP crystal option saves power. A set of configuration bits are used to select various options.
There are several features intended to maximize system reliability, minimize cost through elimination of external components, provide power saving operating modes and offer code protection. These are: * OSC Selection * RESET - Power-on Reset (POR) - Power-up Timer (PWRT) - Oscillator Start-up Timer (OST) - Brown-out Reset (BOR) * Interrupts * Watchdog Timer (WDT) * SLEEP * Code Protection * ID Locations * In-circuit Serial Programming All PIC18CXX2 devices have a Watchdog Timer, which is permanently enabled via the configuration bits or software-controlled. It runs off its own RC oscillator for added reliability. There are two timers that offer necessary delays on power-up. One is the Oscillator Start-up Timer (OST), intended to keep the chip in RESET until the crystal oscillator is stable. The other is the Powerup Timer (PWRT), which provides a fixed delay on power-up only, designed to keep the part in RESET while the power supply stabilizes. With these two timers on-chip, most applications need no external RESET circuitry.
18.1
Configuration Bits
The configuration bits can be programmed (read as '0'), or left unprogrammed (read as '1'), to select various device configurations. These bits are mapped starting at program memory location 300000h. The user will note that address 300000h is beyond the user program memory space. In fact, it belongs to the configuration memory space (300000h - 3FFFFFh), which can only be accessed using table reads and table writes.
TABLE 18-1:
File Name 300000h 300001h 300002h 300003h 300005h 300006h
CONFIGURATION BITS AND DEVICE IDS
Bit 7 CP -- -- -- -- -- DEV2 DEV10 Bit 6 CP -- -- -- -- -- DEV1 DEV9 Bit 5 CP OSCSEN -- -- -- -- DEV0 DEV8 Bit 4 CP -- -- -- -- -- REV4 DEV7 Bit 3 CP -- BORV1 WDTPS2 -- -- REV3 DEV6 Bit 2 CP FOSC2 BORV0 WDTPS1 -- -- REV2 DEV5 Bit 1 CP FOSC1 BODEN WDTPS0 -- LVEN REV1 DEV4 Bit 0 CP FOSC0 PWRTEN WDTEN CCP2MX STVREN REV0 DEV3 Default/ Unprogrammed Value
1111 1111 111- -111 ---- 1111 ---- 1111 ---- ---1 ---- --11 0000 0000 0000 0010
CONFIG1L CONFIG1H CONFIG2L CONFIG2H CONFIG3H CONFIG4L
3FFFFEh DEVID1 3FFFFFh DEVID2
Legend: x = unknown, u = unchanged, - = unimplemented, q = value depends on condition. Shaded cells are unimplemented, read as `0'
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REGISTER 18-1: CONFIGURATION REGISTER 1 HIGH (CONFIG1H: BYTE ADDRESS 300001h)
R/P-1 Reserved bit 7 bit 7-6 bit 5 Reserved: Read as '1' OSCSEN: Oscillator System Clock Switch Enable bit 1 = Oscillator system clock switch option is disabled (main oscillator is source) 0 = Oscillator system clock switch option is enabled (oscillator switching is enabled) Unimplemented: Read as '0' FOSC2:FOSC0: Oscillator Selection bits 111 = RC oscillator w/OSC2 configured as RA6 110 = HS oscillator with PLL enabled/Clock frequency = (4 x FOSC) 101 = EC oscillator w/OSC2 configured as RA6 100 = EC oscillator w/OSC2 configured as divide-by-4 clock output 011 = RC oscillator 010 = HS oscillator 001 = XT oscillator 000 = LP oscillator Legend: R = Readable bit P = Programmable bit U = Unimplemented bit, read as `0' u = Unchanged from programmed state - n = Value when device is unprogrammed R/P-1 Reserved R/P-1 OSCSEN U-0 -- U-0 -- R/P-1 FOSC2 R/P-1 FOSC1 R/P-1 FOSC0 bit 0
bit 4-3 bit 2-0
REGISTER 18-2:
CONFIGURATION REGISTER 1 LOW (CONFIG1L: BYTE ADDRESS 300000h)
R/P-1 CP bit 7 R/P-1 CP R/P-1 CP R/P-1 CP R/P-1 CP R/P-1 CP R/P-1 CP R/P-1 CP bit 0
bit 7-0
CP: Code Protection bits (apply when in Code Protected Microcontroller mode) 1 = Program memory code protection off 0 = All of program memory code protected Legend: R = Readable bit P = Programmable bit U = Unimplemented bit, read as `0' u = Unchanged from programmed state - n = Value when device is unprogrammed
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REGISTER 18-3: CONFIGURATION REGISTER 2 HIGH (CONFIG2H: BYTE ADDRESS 300003h)
U-0 -- bit 7 bit 7-4 bit 3-1 Unimplemented: Read as '0' WDTPS2:WDTPS0: Watchdog Timer Postscale Select bits 111 = 1:1 110 = 1:2 101 = 1:4 100 = 1:8 011 = 1:16 010 = 1:32 001 = 1:64 000 = 1:128 WDTEN: Watchdog Timer Enable bit 1 = WDT enabled 0 = WDT disabled (control is placed on the SWDTEN bit) Legend: R = Readable bit P = Programmable bit U = Unimplemented bit, read as `0' u = Unchanged from programmed state - n = Value when device is unprogrammed U-0 -- U-0 -- U-0 -- R/P-1 WDTPS2 R/P-1 WDTPS1 R/P-1 WDTPS0 R/P-1 WDTEN bit 0
bit 0
REGISTER 18-4:
CONFIGURATION REGISTER 2 LOW (CONFIG2L: BYTE ADDRESS 300002h)
U-0 -- bit 7 U-0 -- U-0 -- U-0 -- R/P-1 BORV1 R/P-1 BORV0 R/P-1 BOREN R/P-1 PWRTEN bit 0
bit 7-4 bit 3-2
Unimplemented: Read as '0' BORV1:BORV0: Brown-out Reset Voltage bits 11 = VBOR set to 2.5V 10 = VBOR set to 2.7V 01 = VBOR set to 4.2V 00 = VBOR set to 4.5V BOREN: Brown-out Reset Enable bit(1) 1 = Brown-out Reset enabled 0 = Brown-out Reset disabled Note: Enabling Brown-out Reset automatically enables the Power-up Timer (PWRT), regardless of the value of bit PWRTEN. Ensure the Power-up Timer is enabled any time Brown-out Reset is enabled.
bit 1
bit 0
PWRTEN: Power-up Timer Enable bit(1) 1 = PWRT disabled 0 = PWRT enabled Note: Enabling Brown-out Reset automatically enables the Power-up Timer (PWRT), regardless of the value of bit PWRTE. Ensure the Power-up Timer is enabled any time Brown-out Reset is enabled.
Legend: R = Readable bit P = Programmable bit U = Unimplemented bit, read as `0' u = Unchanged from programmed state - n = Value when device is unprogrammed
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REGISTER 18-5: CONFIGURATION REGISTER 3 HIGH (CONFIG3H: BYTE ADDRESS 300005h)
U-0 -- bit 7 bit 7-1 bit 0 Unimplemented: Read as '0' CCP2MX: CCP2 Mux bit 1 = CCP2 input/output is multiplexed with RC1 0 = CCP2 input/output is multiplexed with RB3 Legend: R = Readable bit P = Programmable bit U = Unimplemented bit, read as `0' u = Unchanged from programmed state - n = Value when device is unprogrammed U-0 -- U-0 -- U-0 -- U-0 -- U-0 -- U-0 -- R/P-1 CCP2MX bit 0
REGISTER 18-6:
CONFIGURATION REGISTER 4 LOW (CONFIG4L: BYTE ADDRESS 300006h)
U-0 -- bit 7 U-0 -- U-0 -- U-0 -- U-0 -- U-0 -- R/P-1 Reserved R/P-1 STVREN bit 0
bit 7-2 bit 1 bit 0
Unimplemented: Read as '0' Reserved: Maintain this bit set STVREN: Stack Full/Underflow Reset Enable bit 1 = Stack Full/Underflow will cause RESET 0 = Stack Full/Underflow will not cause RESET Legend: R = Readable bit P = Programmable bit U = Unimplemented bit, read as `0' u = Unchanged from programmed state - n = Value when device is unprogrammed
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18.2 Watchdog Timer (WDT)
The Watchdog Timer is a free running, on-chip RC oscillator, which does not require any external components. This RC oscillator is separate from the RC oscillator of the OSC1/CLKI pin. That means that the WDT will run, even if the clock on the OSC1/CLKI and OSC2/ CLKO/RA6 pins of the device has been stopped, for example, by execution of a SLEEP instruction. During normal operation, a WDT time-out generates a device RESET (Watchdog Timer Reset). If the device is in SLEEP mode, a WDT time-out causes the device to wake-up and continue with normal operation (Watchdog Timer Wake-up). The TO bit in the RCON register will be cleared upon a WDT time-out. The Watchdog Timer is enabled/disabled by a device configuration bit. If the WDT is enabled, software execution may not disable this function. When the WDTEN configuration bit is cleared, the SWDTEN bit enables/ disables the operation of the WDT. The WDT time-out period values may be found in the Electrical Specifications section under parameter #31. Values for the WDT postscaler may be assigned using the configuration bits. Note: The CLRWDT and SLEEP instructions clear the WDT and the postscaler, if assigned to the WDT, and prevent it from timing out and generating a device RESET condition.
Note:
When a CLRWDT instruction is executed and the postscaler is assigned to the WDT, the postscaler count will be cleared, but the postscaler assignment is not changed.
18.2.1
CONTROL REGISTER
Register 18-7 shows the WDTCON register. This is a readable and writable register, which contains a control bit that allows software to override the WDT enable configuration bit, only when the configuration bit has disabled the WDT.
REGISTER 18-7:
WDTCON REGISTER
U-0 -- bit 7 U-0 -- U-0 -- U-0 -- U-0 -- U-0 -- U-0 -- R/W-0 SWDTEN bit 0
bit 7-1 bit 0
Unimplemented: Read as '0' SWDTEN: Software Controlled Watchdog Timer Enable bit 1 = Watchdog Timer is on 0 = Watchdog Timer is turned off if the WDTEN configuration bit in the configuration register = '0' Legend: R = Readable bit U = Unimplemented bit, read as `0' W = Writable bit - n = Value at POR Reset
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18.2.2 WDT POSTSCALER
The WDT has a postscaler that can extend the WDT Reset period. The postscaler is selected at the time of device programming, by the value written to the CONFIG2H configuration register.
FIGURE 18-1:
WATCHDOG TIMER BLOCK DIAGRAM
WDT Timer
Postscaler 8 8 - to - 1 MUX WDTPS2:WDTPS0
WDTEN Configuration bit
SWDTEN bit
WDT Time-out Note: WDPS2:WDPS0 are bits in register CONFIG2H.
TABLE 18-2:
Name CONFIG2H RCON WDTCON
SUMMARY OF WATCHDOG TIMER REGISTERS
Bit 7 -- IPEN -- Bit 6 -- LWRT -- Bit 5 -- -- -- Bit 4 -- RI -- Bit 3 WDTPS2 TO -- Bit 2 WDTPS2 PD -- Bit 1 WDTPS0 POR -- Bit 0 WDTEN BOR SWDTEN
Legend: Shaded cells are not used by the Watchdog Timer.
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18.3 Power-down Mode (SLEEP)
Power-down mode is entered by executing a SLEEP instruction. If enabled, the Watchdog Timer will be cleared, but keeps running, the PD bit (RCON<3>) is cleared, the TO (RCON<4>) bit is set, and the oscillator driver is turned off. The I/O ports maintain the status they had before the SLEEP instruction was executed (driving high, low, or hi-impedance). For lowest current consumption in this mode, place all I/O pins at either VDD or VSS, ensure no external circuitry is drawing current from the I/O pin, power-down the A/D and disable external clocks. Pull all I/O pins that are hi-impedance inputs, high or low externally, to avoid switching currents caused by floating inputs. The T0CKI input should also be at VDD or VSS for lowest current consumption. The contribution from on-chip pull-ups on PORTB should be considered. The MCLR pin must be at a logic high level (VIHMC). When the SLEEP instruction is being executed, the next instruction (PC + 2) is pre-fetched. For the device to wake-up through an interrupt event, the corresponding interrupt enable bit must be set (enabled). Wake-up is regardless of the state of the GIE bit. If the GIE bit is clear (disabled), the device continues execution at the instruction after the SLEEP instruction. If the GIE bit is set (enabled), the device executes the instruction after the SLEEP instruction and then branches to the interrupt address. In cases where the execution of the instruction following SLEEP is not desirable, the user should have a NOP after the SLEEP instruction.
18.3.2
WAKE-UP USING INTERRUPTS
When global interrupts are disabled (GIE cleared) and any interrupt source has both its interrupt enable bit and interrupt flag bit set, one of the following will occur: * If an interrupt condition (interrupt flag bit and interrupt enable bits are set) occurs before the execution of a SLEEP instruction, the SLEEP instruction will complete as a NOP. Therefore, the WDT and WDT postscaler will not be cleared, the TO bit will not be set and PD bits will not be cleared. * If the interrupt condition occurs during or after the execution of a SLEEP instruction, the device will immediately wake up from SLEEP. The SLEEP instruction will be completely executed before the wake-up. Therefore, the WDT and WDT postscaler will be cleared, the TO bit will be set and the PD bit will be cleared. Even if the flag bits were checked before executing a SLEEP instruction, it may be possible for flag bits to become set before the SLEEP instruction completes. To determine whether a SLEEP instruction executed, test the PD bit. If the PD bit is set, the SLEEP instruction was executed as a NOP. To ensure that the WDT is cleared, a CLRWDT instruction should be executed before a SLEEP instruction.
18.3.1
WAKE-UP FROM SLEEP
The device can wake up from SLEEP through one of the following events: 1. 2. 3. External RESET input on MCLR pin. Watchdog Timer Wake-up (if WDT was enabled). Interrupt from INT pin, RB port change, or a Peripheral Interrupt.
The following peripheral interrupts can wake the device from SLEEP: 1. 2. 3. 4. 5. 6. 7. 8. 9. PSP read or write. TMR1 interrupt. Timer1 must be operating as an asynchronous counter. TMR3 interrupt. Timer3 must be operating as an asynchronous counter. CCP capture mode interrupt. Special event trigger (Timer1 in Asynchronous mode using an external clock). MSSP (START/STOP) bit detect interrupt. MSSP transmit or receive in Slave mode (SPI/I2C). USART RX or TX (Synchronous Slave mode). A/D conversion (when A/D clock source is RC).
Other peripherals cannot generate interrupts, since during SLEEP, no on-chip clocks are present. External MCLR Reset will cause a device RESET. All other events are considered a continuation of program execution and will cause a "wake-up". The TO and PD bits in the RCON register can be used to determine the cause of the device RESET. The PD bit, which is set on power-up, is cleared when SLEEP is invoked. The TO bit is cleared, if a WDT time-out occurred (and caused wake-up).
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FIGURE 18-2:
OSC1 CLKOUT(4) INT pin INTF Flag (INTCON<1>) GIEH bit (INTCON<7>) INSTRUCTION FLOW PC Instruction Fetched Instruction Executed PC Inst(PC) = SLEEP Inst(PC - 1) PC+2 Inst(PC + 2) SLEEP PC+4 PC+4 Inst(PC + 4) Inst(PC + 2) Dummy cycle PC + 4 0008h Inst(0008h) Dummy cycle 000Ah Inst(000Ah) Inst(0008h) Processor in SLEEP Interrupt Latency(3) TOST(2)
WAKE-UP FROM SLEEP THROUGH INTERRUPT(1,2)
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4
Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1
Note 1: 2: 3: 4:
XT, HS or LP oscillator mode assumed. GIE = '1' assumed. In this case, after wake- up, the processor jumps to the interrupt routine. If GIE = '0', execution will continue in-line. TOST = 1024TOSC (drawing not to scale) This delay will not occur for RC and EC osc modes. CLKOUT is not available in these osc modes, but shown here for timing reference.
18.4
Program Verification/Code Protection
18.6
In-Circuit Serial Programming
If the code protection bit(s) have not been programmed, the on-chip program memory can be read out for verification purposes. Note: Microchip Technology does not recommend code protecting windowed devices.
18.5
ID Locations
PIC18CXXX microcontrollers can be serially programmed while in the end application circuit. This is simply done with two lines for clock and data, and three other lines for power, ground and the programming voltage. This allows customers to manufacture boards with unprogrammed devices, and then program the microcontroller just before shipping the product. This also allows the most recent firmware or a custom firmware to be programmed.
Five memory locations (200000h - 200004h) are designated as ID locations, where the user can store checksum or other code identification numbers. These locations are accessible during normal execution through the TBLRD instruction or during program/verify. The ID locations can be read when the device is code protected.
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19.0 INSTRUCTION SET SUMMARY
The control instructions may use some of the following operands: * A program memory address (specified by `n') * The mode of the Call or Return instructions (specified by `s') * The mode of the Table Read and Table Write instructions (specified by `m') * No operand required (specified by `--') All instructions are a single word, except for three double word instructions. These three instructions were made double word instructions so that all the required information is available in these 32-bits. In the second word, the 4 MSb's are 1's. If this second word is executed as an instruction (by itself), it will execute as a NOP. All single word instructions are executed in a single instruction cycle, unless a conditional test is true or the program counter is changed as a result of the instruction. In these cases, the execution takes two instruction cycles, with the additional instruction cycle(s) executed as a NOP. The double word instructions execute in two instruction cycles. One instruction cycle consists of four oscillator periods. Thus, for an oscillator frequency of 4 MHz, the normal instruction execution time is 1 s. If a conditional test is true, or the program counter is changed as a result of an instruction, the instruction execution time is 2 s. Two word branch instructions (if true) would take 3 s. Figure 19-1 shows the general formats that the instructions can have. All examples use the format `nnh' to represent a hexadecimal number, where `h' signifies a hexadecimal digit. The Instruction Set Summary, shown in Table 19-2, lists the instructions recognized by the Microchip assembler (MPASMTM). Section 19.1 provides a description of each instruction. The PIC18CXXX instruction set adds many enhancements to the previous PICmicro instruction sets, while maintaining an easy migration from these PICmicro instruction sets. Most instructions are a single program memory word (16-bits), but there are three instructions that require two program memory locations. Each single word instruction is a 16-bit word divided into an OPCODE, which specifies the instruction type and one or more operands, which further specify the operation of the instruction. The instruction set is highly orthogonal and is grouped into four basic categories: * * * * Byte-oriented operations Bit-oriented operations Literal operations Control operations
The PIC18CXXX instruction set summary in Table 19-2 lists byte-oriented, bit-oriented, literal and control operations. Table 19-1 shows the opcode field descriptions. Most byte-oriented instructions have three operands: 1. 2. 3. The file register (specified by `f') The destination of the result (specified by `d') The accessed memory (specified by `a')
The file register designator 'f' specifies which file register is to be used by the instruction. The destination designator `d' specifies where the result of the operation is to be placed. If 'd' is zero, the result is placed in the WREG register. If 'd' is one, the result is placed in the file register specified in the instruction. All bit-oriented instructions have three operands: 1. 2. 3. The file register (specified by `f') The bit in the file register (specified by `b') The accessed memory (specified by `a')
The bit field designator 'b' selects the number of the bit affected by the operation, while the file register designator 'f' represents the number of the file in which the bit is located. The literal instructions may use some of the following operands: * A literal value to be loaded into a file register (specified by `k') * The desired FSR register to load the literal value into (specified by `f') * No operand required (specified by `--')
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TABLE 19-1:
Field
a
OPCODE FIELD DESCRIPTIONS
Description RAM access bit a = 0: RAM location in Access RAM (BSR register is ignored) a = 1: RAM bank is specified by BSR register Bit address within an 8-bit file register (0 to 7) Bank Select Register. Used to select the current RAM bank. Destination select bit; d = 0: store result in WREG, d = 1: store result in file register f. Destination either the WREG register or the specified register file location 8-bit Register file address (0x00 to 0xFF) 12-bit Register file address (0x000 to 0xFFF). This is the source address. 12-bit Register file address (0x000 to 0xFFF). This is the destination address. Literal field, constant data or label (may be either an 8-bit, 12-bit or a 20-bit value) Label name The mode of the TBLPTR register for the Table Read and Table Write instructions Only used with Table Read and Table Write instructions: No Change to register (such as TBLPTR with Table reads and writes) Post-Increment register (such as TBLPTR with Table reads and writes) Post-Decrement register (such as TBLPTR with Table reads and writes) Pre-Increment register (such as TBLPTR with Table reads and writes) The relative address (2's complement number) for relative branch instructions, or the direct address for Call/Branch and Return instructions Product of Multiply high byte Product of Multiply low byte Fast Call/Return mode select bit. s = 0: do not update into/from shadow registers s = 1: certain registers loaded into/from shadow registers (Fast mode) Unused or Unchanged Working register (accumulator) Don't care (0 or 1) The assembler will generate code with x = 0. It is the recommended form of use for compatibility with all Microchip software tools. 21-bit Table Pointer (points to a Program Memory location) 8-bit Table Latch Top-of-Stack Program Counter Program Counter Low Byte Program Counter High Byte Program Counter High Byte Latch Program Counter Upper Byte Latch Global Interrupt Enable bit Watchdog Timer Time-out bit Power-down bit ALU status bits Carry, Digit Carry, Zero, Overflow, Negative Optional Contents Assigned to Register bit field In the set of User defined term (font is courier)
bbb BSR d
dest f fs fd k label mm * *+ *+* n PRODH PRODL s
u WREG x
TBLPTR TABLAT TOS PC PCL PCH PCLATH PCLATU GIE WDT TO PD C, DC, Z, OV, N [ ( ] )
<>
italics
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PIC18CXX2
FIGURE 19-1: GENERAL FORMAT FOR INSTRUCTIONS
Byte-oriented file register operations 15 10 9 87 OPCODE d a 0 f (FILE #) ADDWF MYREG, W, B Example Instruction
d = 0 for result destination to be WREG register d = 1 for result destination to be file register (f) a = 0 to force Access Bank a = 1 for BSR to select bank f = 8-bit file register address Byte to Byte move operations (2-word) 15 12 11 OPCODE 15 12 11
1111
0 f (Source FILE #) 0 f (Destination FILE #) MOVFF MYREG1, MYREG2
f = 12-bit file register address Bit-oriented file register operations 15 12 11 98 7 f (FILE #) 0 BSF MYREG, bit, B
OPCODE b (BIT #) a
b = 3-bit position of bit in file register (f) a = 0 to force Access Bank a = 1 for BSR to select bank f = 8-bit file register address Literal operations 15 OPCODE k = 8-bit immediate value Control operations CALL, GOTO and Branch operations 15 OPCODE 15
1111
8
7 k (literal)
0 MOVLW 0x7F
87 n<7:0> (literal)
0 GOTO Label
12 11 n<19:8> (literal)
0
n = 20-bit immediate value 15 OPCODE 15 12 11 n<19:8> (literal) S = Fast bit 15 OPCODE 15 OPCODE 11 10 n<10:0> (literal) 87 n<7:0> (literal) 0 BC MYFUNC 0 BRA MYFUNC 87 S n<7:0> (literal) 0 0 CALL MYFUNC
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TABLE 19-2:
Mnemonic, Operands
PIC18CXXX INSTRUCTION SET
16-bit Instruction Word Description Cycles MSb LSb Status Affected Notes
BYTE-ORIENTED FILE REGISTER OPERATIONS ADDWF 1 f, d, a Add WREG and f 0010 01da ffff ffff C, DC, Z, OV, N 1, 2 ADDWFC f, d, a Add WREG and Carry bit to f 1 0010 00da ffff ffff C, DC, Z, OV, N 1, 2 ANDWF 1 f, d, a AND WREG with f 0001 01da ffff ffff Z, N 1,2 Clear f CLRF 1 f, a 0110 101a ffff ffff Z 2 COMF 1 f, d, a Complement f 0001 11da ffff ffff Z, N 1, 2 Compare f with WREG, skip = CPFSEQ 1 (2 or 3) 0110 001a ffff ffff None f, a 4 Compare f with WREG, skip > CPFSGT 1 (2 or 3) 0110 010a ffff ffff None f, a 4 Compare f with WREG, skip < CPFSLT 1 (2 or 3) 0110 000a ffff ffff None f, a 1, 2 DECF 1 f, d, a Decrement f 0000 01da ffff ffff C, DC, Z, OV, N 1, 2, 3, 4 DECFSZ 1 (2 or 3) 0010 11da ffff ffff None f, d, a Decrement f, Skip if 0 1, 2, 3, 4 DCFSNZ 1 (2 or 3) 0100 11da ffff ffff None f, d, a Decrement f, Skip if Not 0 1, 2 INCF 1 f, d, a Increment f 0010 10da ffff ffff C, DC, Z, OV, N 1, 2, 3, 4 INCFSZ 1 (2 or 3) 0011 11da ffff ffff None f, d, a Increment f, Skip if 0 4 INFSNZ 1 (2 or 3) 0100 10da ffff ffff None f, d, a Increment f, Skip if Not 0 1, 2 IORWF 1 f, d, a Inclusive OR WREG with f 0001 00da ffff ffff Z, N 1, 2 MOVF 1 f, d, a Move f 0101 00da ffff ffff Z, N 1 MOVFF 2 fs, fd Move fs (source) to 1st word 1100 ffff ffff ffff None fd (destination)2nd word 1111 ffff ffff ffff f, a Move WREG to f MOVWF 1 0110 111a ffff ffff None f, a Multiply WREG with f MULWF 1 0000 001a ffff ffff None f, a Negate f NEGF 1 0110 110a ffff ffff C, DC, Z, OV, N 1, 2 f, d, a Rotate Left f through Carry RLCF 1 0011 01da ffff ffff C, Z, N f, d, a Rotate Left f (No Carry) RLNCF 1 0100 01da ffff ffff Z, N 1, 2 f, d, a Rotate Right f through Carry RRCF 1 0011 00da ffff ffff C, Z, N f, d, a Rotate Right f (No Carry) RRNCF 1 0100 00da ffff ffff Z, N f, a Set f SETF 1 0110 100a ffff ffff None SUBFWB f, d, a Subtract f from WREG with 1 0101 01da ffff ffff C, DC, Z, OV, N 1, 2 borrow f, d, a Subtract WREG from f SUBWF 1 0101 11da ffff ffff C, DC, Z, OV, N SUBWFB f, d, a Subtract WREG from f with 1 0101 10da ffff ffff C, DC, Z, OV, N 1, 2 borrow f, d, a Swap nibbles in f SWAPF 1 0011 10da ffff ffff None 4 f, a Test f, skip if 0 TSTFSZ 1 (2 or 3) 0110 011a ffff ffff None 1, 2 f, d, a Exclusive OR WREG with f XORWF 1 0001 10da ffff ffff Z, N BIT-ORIENTED FILE REGISTER OPERATIONS BCF f, b, a Bit Clear f 1 1001 bbba ffff ffff None 1, 2 BSF f, b, a Bit Set f 1 1000 bbba ffff ffff None 1, 2 BTFSC f, b, a Bit Test f, Skip if Clear 1 (2 or 3) 1011 bbba ffff ffff None 3, 4 BTFSS f, b, a Bit Test f, Skip if Set 1 (2 or 3) 1010 bbba ffff ffff None 3, 4 BTG f, d, a Bit Toggle f 1 0111 bbba ffff ffff None 1, 2 Note 1: When a PORT register is modified as a function of itself (e.g., MOVF PORTB, 1, 0), the value used will be that value present on the pins themselves. For example, if the data latch is '1' for a pin configured as input and is driven low by an external device, the data will be written back with a '0'. 2: If this instruction is executed on the TMR0 register (and, where applicable, d = 1), the prescaler will be cleared if assigned. 3: If Program Counter (PC) is modified or a conditional test is true, the instruction requires two cycles. The second cycle is executed as a NOP. 4: Some instructions are 2 word instructions. The second word of these instructions will be executed as a NOP, unless the first word of the instruction retrieves the information embedded in these 16-bits. This ensures that all program memory locations have a valid instruction. 5: If the table write starts the write cycle to internal memory, the write will continue until terminated.
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TABLE 19-2:
Mnemonic, Operands
PIC18CXXX INSTRUCTION SET (CONTINUED)
16-bit Instruction Word Description Cycles MSb 1 (2) 1 (2) 1 (2) 1 (2) 1 (2) 2 1 (2) 1 (2) 1 (2) 2 1 1 2 1 1 1 1 2 1 2 1110 1110 1110 1110 1110 1110 1110 1101 1110 1110 1111 0000 0000 1110 1111 0000 1111 0000 0000 1101 0000 0000 0010 0110 0011 0111 0101 0001 0100 0nnn 0000 110s kkkk 0000 0000 1111 kkkk 0000 xxxx 0000 0000 1nnn 0000 0000 nnnn nnnn nnnn nnnn nnnn nnnn nnnn nnnn nnnn kkkk kkkk 0000 0000 kkkk kkkk 0000 xxxx 0000 0000 nnnn 1111 0001 LSb nnnn nnnn nnnn nnnn nnnn nnnn nnnn nnnn nnnn kkkk kkkk 0100 0111 kkkk kkkk 0000 xxxx 0110 0101 nnnn 1111 000s Status Affected Notes
None None None None None All GIE/GIEH, PEIE/GIEL RETLW k Return with literal in WREG 2 0000 1100 kkkk kkkk None RETURN s Return from Subroutine 2 0000 0000 0001 001s None SLEEP -- Go into standby mode 1 0000 0000 0000 0011 TO, PD Note 1: When a PORT register is modified as a function of itself (e.g., MOVF PORTB, 1, 0), the value used will be that value present on the pins themselves. For example, if the data latch is '1' for a pin configured as input and is driven low by an external device, the data will be written back with a '0'. 2: If this instruction is executed on the TMR0 register (and, where applicable, d = 1), the prescaler will be cleared if assigned. 3: If Program Counter (PC) is modified or a conditional test is true, the instruction requires two cycles. The second cycle is executed as a NOP. 4: Some instructions are 2 word instructions. The second word of these instructions will be executed as a NOP, unless the first word of the instruction retrieves the information embedded in these 16-bits. This ensures that all program memory locations have a valid instruction. 5: If the table write starts the write cycle to internal memory, the write will continue until terminated.
CONTROL OPERATIONS BC n Branch if Carry BN n Branch if Negative BNC n Branch if Not Carry BNN n Branch if Not Negative BNOV n Branch if Not Overflow BNZ n Branch if Not Zero BOV n Branch if Overflow BRA n Branch Unconditionally BZ n Branch if Zero CALL n, s Call subroutine1st word 2nd word CLRWDT -- Clear Watchdog Timer DAW -- Decimal Adjust WREG GOTO n Go to address1st word 2nd word NOP -- No Operation NOP -- No Operation (Note 4) POP -- Pop top of return stack (TOS) PUSH -- Push top of return stack (TOS) RCALL n Relative Call RESET Software device RESET RETFIE s Return from interrupt enable
None None None None None None None None None None TO, PD C None
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TABLE 19-2:
Mnemonic, Operands
PIC18CXXX INSTRUCTION SET (CONTINUED)
16-bit Instruction Word Description Cycles MSb LSb Status Affected Notes
LITERAL OPERATIONS ADDLW k Add literal and WREG 1 0000 1111 kkkk kkkk C, DC, Z, OV, N ANDLW k AND literal with WREG 1 0000 1011 kkkk kkkk Z, N IORLW k Inclusive OR literal with WREG 1 0000 1001 kkkk kkkk Z, N LFSR f, k Move literal (12-bit) 2nd word 2 1110 1110 00ff kkkk None to FSRx 1st word 1111 0000 kkkk kkkk MOVLB k Move literal to BSR<3:0> 1 0000 0001 0000 kkkk None MOVLW k Move literal to WREG 1 0000 1110 kkkk kkkk None MULLW k Multiply literal with WREG 1 0000 1101 kkkk kkkk None RETLW k Return with literal in WREG 2 0000 1100 kkkk kkkk None SUBLW k Subtract WREG from literal 1 0000 1000 kkkk kkkk C, DC, Z, OV, N XORLW k Exclusive OR literal with WREG 1 0000 1010 kkkk kkkk Z, N DATA MEMORY PROGRAM MEMORY OPERATIONS TBLRD* Table Read 2 0000 0000 0000 1000 None TBLRD*+ Table Read with post-increment 0000 0000 0000 1001 None TBLRD*Table Read with post-decrement 0000 0000 0000 1010 None TBLRD+* Table Read with pre-increment 0000 0000 0000 1011 None TBLWT* Table Write 2 (5) 0000 0000 0000 1100 None TBLWT*+ Table Write with post-increment 0000 0000 0000 1101 None TBLWT*Table Write with post-decrement 0000 0000 0000 1110 None TBLWT+* Table Write with pre-increment 0000 0000 0000 1111 None Note 1: When a PORT register is modified as a function of itself (e.g., MOVF PORTB, 1, 0), the value used will be that value present on the pins themselves. For example, if the data latch is '1' for a pin configured as input and is driven low by an external device, the data will be written back with a '0'. 2: If this instruction is executed on the TMR0 register (and, where applicable, d = 1), the prescaler will be cleared if assigned. 3: If Program Counter (PC) is modified or a conditional test is true, the instruction requires two cycles. The second cycle is executed as a NOP. 4: Some instructions are 2 word instructions. The second word of these instructions will be executed as a NOP, unless the first word of the instruction retrieves the information embedded in these 16-bits. This ensures that all program memory locations have a valid instruction. 5: If the table write starts the write cycle to internal memory, the write will continue until terminated.
DS39026C-page 192
2001 Microchip Technology Inc.
PIC18CXX2
19.1
ADDLW Syntax: Operands: Operation: Status Affected: Encoding: Description:
Instruction Set
ADD literal to WREG [ label ] ADDLW 0 k 255 (WREG) + k WREG N,OV, C, DC, Z
0000 1111 kkkk kkkk
ADDWF Syntax: Operands:
ADD WREG to f [ label ] ADDWF 0 f 255 d [0,1] a [0,1] (WREG) + (f) dest N,OV, C, DC, Z
0010 01da ffff ffff
k
f [,d [,a] f [,d [,a]
Operation: Status Affected: Encoding: Description:
The contents of WREG are added to the 8-bit literal 'k' and the result is placed in WREG. 1 1 Q2
Read literal 'k'
ADDLW
Words: Cycles: Q Cycle Activity: Q1
Decode
Q3
Process Data
0x15
Q4
Write to WREG
Add WREG to register 'f'. If 'd' is 0, the result is stored in WREG. If 'd' is 1, the result is stored back in register 'f' (default). If `a' is 0, the Access Bank will be selected. If `a' is 1, the BSR is used. 1 1 Q2
Read register 'f'
ADDWF
Words: Cycles: Q Cycle Activity: Q1
Decode
Example:
Before Instruction
WREG = 0x10
Q3
Process Data
REG, 0, 0
Q4
Write to destination
After Instruction
WREG = 0x25
Example:
WREG REG WREG REG = = = =
Before Instruction
0x17 0xC2 0xD9 0xC2
After Instruction
2001 Microchip Technology Inc.
DS39026C-page 193
PIC18CXX2
ADDWFC Syntax: Operands: ADD WREG and Carry bit to f [ label ] ADDWFC 0 f 255 d [0,1] a [0,1] (WREG) + (f) + (C) dest N,OV, C, DC, Z
0010 00da ffff ffff
ANDLW Syntax: Operands: Operation: Status Affected: Encoding: Description:
AND literal with WREG [ label ] ANDLW 0 k 255 (WREG) .AND. k WREG N,Z
0000 1011 kkkk kkkk
f [,d [,a]
k
Operation: Status Affected: Encoding: Description:
Add WREG, the Carry Flag and data memory location 'f'. If 'd' is 0, the result is placed in WREG. If 'd' is 1, the result is placed in data memory location 'f'. If `a' is 0, the Access Bank will be selected. If `a' is 1, the BSR will not be overridden. 1 1
The contents of WREG are ANDed with the 8-bit literal 'k'. The result is placed in WREG. 1 1 Q2
Read literal 'k'
ANDLW
Words: Cycles: Q Cycle Activity: Q1
Decode
Q3
Process Data
0x5F
Q4
Write to WREG
Words: Cycles: Q Cycle Activity: Q1
Decode
Example: Q2
Read register 'f'
ADDWFC
Q3
Process Data
REG, 0, 1
Q4
Write to destination
Before Instruction
WREG = 0xA3
After Instruction
WREG = 0x03
Example:
Before Instruction
Carry bit= 1 REG = 0x02 WREG = 0x4D
After Instruction
Carry bit= 0 REG = 0x02 WREG = 0x50
DS39026C-page 194
2001 Microchip Technology Inc.
PIC18CXX2
ANDWF Syntax: Operands: AND WREG with f [ label ] ANDWF 0 f 255 d [0,1] a [0,1] (WREG) .AND. (f) dest N,Z
0001 01da ffff ffff
BC f [,d [,a] Syntax: Operands: Operation: Status Affected: Encoding: Description:
Branch if Carry [ label ] BC n -128 n 127 if carry bit is '1' (PC) + 2 + 2n PC None
1110 0010 nnnn nnnn
Operation: Status Affected: Encoding: Description:
The contents of WREG are AND'ed with register 'f'. If 'd' is 0, the result is stored in WREG. If 'd' is 1, the result is stored back in register 'f' (default). If `a' is 0, the Access Bank will be selected. If `a' is 1, the BSR will not be overridden (default). 1 1 Q2
Read register 'f'
ANDWF
If the Carry bit is '1', then the program will branch. The 2's complement number '2n' is added to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC+2+2n. This instruction is then a two-cycle instruction. 1 1(2)
Words: Cycles: Q Cycle Activity: If Jump: Q1
Decode No operation
Words: Cycles: Q Cycle Activity: Q1
Decode
Q3
Process Data
REG, 0, 0
Q4
Write to destination
Q2
Read literal 'n' No operation
Q3
Process Data No operation
Q4
Write to PC No operation
Example:
WREG REG WREG REG = = = =
Before Instruction
0x17 0xC2 0x02 0xC2
If No Jump: Q1
Decode
Q2
Read literal 'n'
HERE
Q3
Process Data
BC 5
Q4
No operation
After Instruction Example:
PC
Before Instruction
= = = = = address (HERE) 1; address (HERE+12) 0; address (HERE+2)
After Instruction
If Carry PC If Carry PC
2001 Microchip Technology Inc.
DS39026C-page 195
PIC18CXX2
BCF Syntax: Operands: Bit Clear f [ label ] BCF 0 f 255 0b7 a [0,1] 0 f None
1001 bbba ffff ffff
BN f,b[,a] Syntax: Operands: Operation: Status Affected: Encoding: Description:
Branch if Negative [ label ] BN n -128 n 127 if negative bit is '1' (PC) + 2 + 2n PC None
1110 0110 nnnn nnnn
Operation: Status Affected: Encoding: Description:
Bit 'b' in register 'f' is cleared. If `a' is 0, the Access Bank will be selected, overriding the BSR value. If `a' = 1, then the bank will be selected as per the BSR value (default). 1 1 Q2
Read register 'f'
BCF
Words: Cycles: Q Cycle Activity: Q1
Decode
If the Negative bit is '1', then the program will branch. The 2's complement number '2n' is added to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC+2+2n. This instruction is then a two-cycle instruction. 1 1(2)
Words: Cycles: Q3
Process Data
FLAG_REG,
Q4
Write register 'f'
7, 0
Q Cycle Activity: If Jump: Q1
Decode
Q2
Read literal 'n' No operation
Q3
Process Data No operation
Q4
Write to PC No operation
Example:
Before Instruction
FLAG_REG = 0xC7
No operation
After Instruction
FLAG_REG = 0x47
If No Jump: Q1
Decode
Q2
Read literal 'n'
HERE
Q3
Process Data
BN Jump
Q4
No operation
Example:
PC
Before Instruction
= address (HERE) 1; address (Jump) 0; address (HERE+2)
After Instruction
If Negative = PC = If Negative = PC =
DS39026C-page 196
2001 Microchip Technology Inc.
PIC18CXX2
BNC Syntax: Operands: Operation: Status Affected: Encoding: Description: Branch if Not Carry [ label ] BNC -128 n 127 if carry bit is '0' (PC) + 2 + 2n PC None
1110 0011 nnnn nnnn
BNN Syntax: Operands: Operation: Status Affected: Encoding: Description:
Branch if Not Negative [ label ] BNN -128 n 127 if negative bit is '0' (PC) + 2 + 2n PC None
1110 0111 nnnn nnnn
n
n
If the Carry bit is '0', then the program will branch. The 2's complement number '2n' is added to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC+2+2n. This instruction is then a two-cycle instruction. 1 1(2)
If the Negative bit is '0', then the program will branch. The 2's complement number '2n' is added to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC+2+2n. This instruction is then a two-cycle instruction. 1 1(2)
Words: Cycles: Q Cycle Activity: If Jump: Q1
Decode No operation
Words: Cycles: Q Cycle Activity: If Jump: Q1
Decode No operation
Q2
Read literal 'n' No operation
Q3
Process Data No operation
Q4
Write to PC No operation
Q2
Read literal 'n' No operation
Q3
Process Data No operation
Q4
Write to PC No operation
If No Jump: Q1
Decode
Q2
Read literal 'n'
HERE
Q3
Process Data
BNC Jump
Q4
No operation
If No Jump: Q1
Decode
Q2
Read literal 'n'
HERE
Q3
Process Data
BNN Jump
Q4
No operation
Example:
PC
Example:
PC
Before Instruction
= = = = = address (HERE) 0; address (Jump) 1; address (HERE+2)
Before Instruction
= address (HERE) 0; address (Jump) 1; address (HERE+2)
After Instruction
If Carry PC If Carry PC
After Instruction
If Negative = PC = If Negative = PC =
2001 Microchip Technology Inc.
DS39026C-page 197
PIC18CXX2
BNOV Syntax: Operands: Operation: Status Affected: Encoding: Description: Branch if Not Overflow [ label ] BNOV -128 n 127 if overflow bit is '0' (PC) + 2 + 2n PC None
1110 0101 nnnn nnnn
BNZ Syntax: Operands: Operation: Status Affected: Encoding: Description:
Branch if Not Zero [ label ] BNZ -128 n 127 if zero bit is '0' (PC) + 2 + 2n PC None
1110 0001 nnnn nnnn
n
n
If the Overflow bit is '0', then the program will branch. The 2's complement number '2n' is added to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC+2+2n. This instruction is then a two-cycle instruction. 1 1(2)
If the Zero bit is '0', then the program will branch. The 2's complement number '2n' is added to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC+2+2n. This instruction is then a two-cycle instruction. 1 1(2)
Words: Cycles: Q Cycle Activity: If Jump: Q1
Decode No operation
Words: Cycles: Q Cycle Activity: If Jump: Q1
Decode No operation
Q2
Read literal 'n' No operation
Q3
Process Data No operation
Q4
Write to PC No operation
Q2
Read literal 'n' No operation
Q3
Process Data No operation
Q4
Write to PC No operation
If No Jump: Q1
Decode
Q2
Read literal 'n'
HERE
Q3
Process Data
BNOV Jump
Q4
No operation
If No Jump: Q1
Decode
Q2
Read literal 'n'
HERE
Q3
Process Data
BNZ Jump
Q4
No operation
Example:
PC
Example:
PC
Before Instruction
= address (HERE) 0; address (Jump) 1; address (HERE+2)
Before Instruction
= = = = = address (HERE) 0; address (Jump) 1; address (HERE+2)
After Instruction
If Overflow = PC = If Overflow = PC =
After Instruction
If Zero PC If Zero PC
DS39026C-page 198
2001 Microchip Technology Inc.
PIC18CXX2
BRA Syntax: Operands: Operation: Status Affected: Encoding: Description: Unconditional Branch [ label ] BRA n -1024 n 1023 (PC) + 2 + 2n PC None
1101 0nnn nnnn nnnn
BSF Syntax: Operands:
Bit Set f [ label ] BSF 0 f 255 0b7 a [0,1] 1 f None
1000 bbba ffff ffff
f,b[,a]
Operation: Status Affected: Encoding: Description:
Add the 2's complement number '2n' to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC+2+2n. This instruction is a twocycle instruction. 1 2 Q2
Read literal 'n' No operation
Words: Cycles: Q Cycle Activity: Q1
Decode No operation
Bit 'b' in register 'f' is set. If `a' is 0 Access Bank will be selected, overriding the BSR value. If `a' = 1, then the bank will be selected as per the BSR value. 1 1 Q2
Read register 'f'
BSF
Words: Cycles: Q3
Process Data No operation
Q4
Write to PC No operation
Q Cycle Activity: Q1
Decode
Q3
Process Data
Q4
Write register 'f'
Example: Example:
PC HERE BRA Jump
FLAG_REG, 7, 1 0x0A 0x8A
Before Instruction
FLAG_REG=
Before Instruction
= = address (HERE) address (Jump)
After Instruction
FLAG_REG=
After Instruction
PC
2001 Microchip Technology Inc.
DS39026C-page 199
PIC18CXX2
BTFSC Syntax: Operands: Bit Test File, Skip if Clear [ label ] BTFSC f,b[,a] 0 f 255 0b7 a [0,1] skip if (f) = 0 None
1011 bbba ffff ffff
BTFSS Syntax: Operands:
Bit Test File, Skip if Set [ label ] BTFSS f,b[,a] 0 f 255 0b<7 a [0,1] skip if (f) = 1 None
1010 bbba ffff ffff
Operation: Status Affected: Encoding: Description:
Operation: Status Affected: Encoding: Description:
If bit 'b' in register 'f' is 0, then the next instruction is skipped. If bit 'b' is 0, then the next instruction fetched during the current instruction execution is discarded, and a NOP is executed instead, making this a twocycle instruction. If `a' is 0, the Access Bank will be selected, overriding the BSR value. If `a' = 1, then the bank will be selected as per the BSR value (default). 1 1(2) Note: 3 cycles if skip and followed by a 2-word instruction. Q2
Read register 'f'
If bit 'b' in register 'f' is 1 then the next instruction is skipped. If bit 'b' is 1, then the next instruction fetched during the current instruction execution, is discarded and a NOP is executed instead, making this a two-cycle instruction. If `a' is 0, the Access Bank will be selected, overriding the BSR value. If `a' = 1, then the bank will be selected as per the BSR value (default). 1 1(2) Note: 3 cycles if skip and followed by a 2-word instruction. Q3
Process Data
Words: Cycles:
Words: Cycles:
Q Cycle Activity: Q1
Decode
Q3
Process Data
Q4
No operation
Q Cycle Activity: Q1
Decode
Q2
Read register 'f'
Q4
No operation
If skip: Q1
No operation
If skip: Q2
No operation
Q3
No operation
Q4
No operation
Q1
No operation
Q2
No operation
Q3
No operation
Q4
No operation
If skip and followed by 2-word instruction: Q1 Q2 Q3
No operation No operation No operation No operation
HERE FALSE TRUE = = = = =
Q4
No operation No operation
If skip and followed by 2-word instruction: Q1 Q2 Q3
No operation No operation No operation No operation
HERE FALSE TRUE = = = = =
Q4
No operation No operation
No operation No operation
BTFSC : :
No operation No operation
BTFSS : :
Example:
FLAG, 1, 0
Example:
FLAG, 1, 0
Before Instruction
PC address (HERE) 0; address (TRUE) 1; address (FALSE)
Before Instruction
PC address (HERE) 0; address (FALSE) 1; address (TRUE)
After Instruction
If FLAG<1> PC If FLAG<1> PC
After Instruction
If FLAG<1> PC If FLAG<1> PC
DS39026C-page 200
2001 Microchip Technology Inc.
PIC18CXX2
BTG Syntax: Operands: Bit Toggle f [ label ] BTG f,b[,a] 0 f 255 0b<7 a [0,1] (f) f None
0111 bbba ffff ffff
BOV Syntax: Operands: Operation: Status Affected: Encoding: Description:
Branch if Overflow [ label ] BOV -128 n 127 if overflow bit is '1' (PC) + 2 + 2n PC None
1110 0100 nnnn nnnn
n
Operation: Status Affected: Encoding: Description:
Bit 'b' in data memory location 'f' is inverted. If `a' is 0, the Access Bank will be selected, overriding the BSR value. If `a' = 1, then the bank will be selected as per the BSR value (default). 1 1 Q2
Read register 'f'
BTG
Words: Cycles: Q Cycle Activity: Q1
Decode
If the Overflow bit is '1', then the program will branch. The 2's complement number '2n' is added to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC+2+2n. This instruction is then a two-cycle instruction. 1 1(2)
Words: Cycles: Q3
Process Data
PORTC, 4, 0
Q4
Write register 'f'
Q Cycle Activity: If Jump: Q1
Decode
Q2
Read literal 'n' No operation
Q3
Process Data No operation
Q4
Write to PC No operation
Example:
PORTC PORTC = =
Before Instruction:
0111 0101 [0x75] 0110 0101 [0x65]
No operation
After Instruction:
If No Jump: Q1
Decode
Q2
Read literal 'n'
HERE
Q3
Process Data
BOV Jump
Q4
No operation
Example:
PC
Before Instruction
= address (HERE) 1; address (Jump) 0; address (HERE+2)
After Instruction
If Overflow = PC = If Overflow = PC =
2001 Microchip Technology Inc.
DS39026C-page 201
PIC18CXX2
BZ Syntax: Operands: Operation: Status Affected: Encoding: Description: Branch if Zero [ label ] BZ n -128 n 127 if Zero bit is '1' (PC) + 2 + 2n PC None
1110 0000 nnnn nnnn
CALL Syntax: Operands: Operation:
Subroutine Call [ label ] CALL k [,s] 0 k 1048575 s [0,1] (PC) + 4 TOS, k PC<20:1>, if s = 1 (WREG) WS, (STATUS) STATUSS, (BSR) BSRS None
1110 1111 110s k19kkk k7kkk kkkk kkkk0 kkkk8
If the Zero bit is '1', then the program will branch. The 2's complement number '2n' is added to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC+2+2n. This instruction is then a two-cycle instruction. 1 1(2)
Status Affected: Encoding: 1st word (k<7:0>) 2nd word(k<19:8>) Description:
Words: Cycles: Q Cycle Activity: If Jump: Q1
Decode No operation
Q2
Read literal 'n' No operation
Q3
Process Data No operation
Q4
Write to PC No operation
Subroutine call of entire 2M byte memory range. First, return address (PC+ 4) is pushed onto the return stack. If 's' = 1, the W, STATUS and BSR registers are also pushed into their respective shadow registers, WS, STATUSS and BSRS. If 's' = 0, no update occurs (default). Then the 20-bit value 'k' is loaded into PC<20:1>. CALL is a two-cycle instruction. 2 2 Q2
Read literal 'k'<7:0>, No operation
HERE
If No Jump: Q1
Decode
Words: Q2
Read literal 'n'
HERE
Q3
Process Data
BZ Jump
Q4
No operation
Cycles: Q Cycle Activity: Q1
Decode
Q3
Push PC to stack No operation
CALL
Q4
Read literal 'k'<19:8>, Write to PC No operation
Example:
PC
Before Instruction
= = = = = address (HERE) 1; address (Jump) 0; address (HERE+2)
After Instruction
If Zero PC If Zero PC
No operation
Example:
PC =
THERE,1
Before Instruction
Address(HERE) Address(THERE) Address (HERE + 4) WREG BSR = STATUS
After Instruction
PC = TOS = WS = BSRS= STATUSS
DS39026C-page 202
2001 Microchip Technology Inc.
PIC18CXX2
CLRF Syntax: Operands: Operation: Status Affected: Encoding: Description: Clear f [label] CLRF 0 f 255 a [0,1] 000h f 1Z Z
0110 101a ffff ffff
CLRWDT f [,a] Syntax: Operands: Operation:
Clear Watchdog Timer [ label ] CLRWDT None 000h WDT, 000h WDT postscaler, 1 TO, 1 PD TO, PD
0000 0000 0000 0100
Status Affected: Encoding: Description:
Clears the contents of the specified register. If `a' is 0, the Access Bank will be selected, overriding the BSR value. If `a' = 1, then the bank will be selected as per the BSR value (default). 1 1 Q2
Read register 'f'
CLRF
CLRWDT instruction resets the Watchdog Timer. It also resets the postscaler of the WDT. Status bits TO and PD are set. 1 1 Q2
No operation
CLRWDT = ? 0x00 0 1 1
Words: Cycles: Q Cycle Activity: Q1
Words: Cycles: Q Cycle Activity: Q1
Decode
Q3
Process Data
Q4
No operation
Q3
Process Data
FLAG_REG,1
Q4
Write register 'f'
Decode
Example: Example:
FLAG_REG
Before Instruction
WDT counter
Before Instruction
= = 0x5A 0x00
After Instruction
WDT counter = WDT Postscaler = TO = PD =
After Instruction
FLAG_REG
2001 Microchip Technology Inc.
DS39026C-page 203
PIC18CXX2
COMF Syntax: Operands: Complement f [ label ] COMF 0 f 255 d [0,1] a [0,1] ( f ) dest N,Z
0001 11da ffff ffff
CPFSEQ f [,d [,a] Syntax: Operands: Operation:
Compare f with WREG, skip if f = WREG [ label ] CPFSEQ 0 f 255 a [0,1] (f) - (WREG), skip if (f) = (WREG) (unsigned comparison) None
0110 001a ffff ffff
f [,a]
Operation: Status Affected: Encoding: Description:
Status Affected: Encoding: Description:
The contents of register 'f' are complemented. If 'd' is 0, the result is stored in WREG. If 'd' is 1, the result is stored back in register 'f' (default). If `a' is 0, the Access Bank will be selected, overriding the BSR value. If `a' = 1, then the bank will be selected as per the BSR value (default). 1 1 Q2
Read register 'f'
COMF = = = 0x13 0x13 0xEC
Words: Cycles: Q Cycle Activity: Q1
Decode
Compares the contents of data memory location 'f' to the contents of WREG by performing an unsigned subtraction. If 'f' = WREG, then the fetched instruction is discarded and a NOP is executed instead, making this a two-cycle instruction. If `a' is 0, the Access Bank will be selected, overriding the BSR value. If `a' = 1, then the bank will be selected as per the BSR value (default). 1 1(2) Note: 3 cycles if skip and followed by a 2-word instruction. Q2
Read register 'f'
Q3
Process Data
REG, 0, 0
Q4
Write to destination
Words: Cycles:
Example:
REG REG WREG
Before Instruction After Instruction
Q Cycle Activity: Q1
Decode
Q3
Process Data
Q4
No operation
If skip: Q1
No operation
Q2
No operation
Q3
No operation
Q4
No operation
If skip and followed by 2-word instruction: Q1 Q2 Q3
No operation No operation No operation No operation
HERE NEQUAL EQUAL
Q4
No operation No operation
No operation No operation
Example:
CPFSEQ REG, 0 : : HERE ? ? WREG; Address (EQUAL) WREG; Address (NEQUAL)
Before Instruction
PC Address = WREG = REG =
After Instruction
If REG PC If REG PC = = =
DS39026C-page 204
2001 Microchip Technology Inc.
PIC18CXX2
CPFSGT Syntax: Operands: Operation: Compare f with WREG, skip if f > WREG [ label ] CPFSGT 0 f 255 a [0,1] (f) - (WREG), skip if (f) > (WREG) (unsigned comparison) None
0110 010a ffff ffff
CPFSLT Syntax: Operands: Operation:
Compare f with WREG, skip if f < WREG [ label ] CPFSLT 0 f 255 a [0,1] (f) - (WREG), skip if (f) < (WREG) (unsigned comparison) None
0110 000a ffff ffff
f [,a]
f [,a]
Status Affected: Encoding: Description:
Status Affected: Encoding: Description:
Compares the contents of data memory location 'f' to the contents of the WREG by performing an unsigned subtraction. If the contents of 'f' are greater than the contents of WREG, then the fetched instruction is discarded and a NOP is executed instead, making this a two-cycle instruction. If `a' is 0, the Access Bank will be selected, overriding the BSR value. If `a' = 1, then the bank will be selected as per the BSR value (default). 1 1(2) Note: 3 cycles if skip and followed by a 2-word instruction. Q2
Read register 'f'
Compares the contents of data memory location 'f' to the contents of WREG by performing an unsigned subtraction. If the contents of 'f' are less than the contents of WREG, then the fetched instruction is discarded and a NOP is executed instead, making this a two-cycle instruction. If `a' is 0, the Access Bank will be selected. If 'a' is 1, the BSR will not be overridden (default). 1 1(2) Note: 3 cycles if skip and followed by a 2-word instruction. Q2
Read register 'f'
Words: Cycles:
Words: Cycles:
Q Cycle Activity: Q1
Decode
Q3
Process Data
Q4
No operation
Q Cycle Activity: Q1
Decode
Q3
Process Data
Q4
No operation
If skip: Q1
No operation
Q2
No operation
Q3
No operation
Q4
No operation
If skip: Q1
No operation
Q2
No operation
Q3
No operation
Q4
No operation
If skip and followed by 2-word instruction: Q1 Q2 Q3
No operation No operation No operation No operation
HERE NLESS LESS = = < =
Q4
No operation No operation
If skip and followed by 2-word instruction: Q1 Q2 Q3
No operation No operation No operation No operation
HERE NGREATER GREATER = =
Q4
No operation No operation
No operation No operation
No operation No operation
Example:
Example:
CPFSGT REG, 0 : :
CPFSLT REG, 1 : : Address (HERE) ? WREG; Address (LESS) WREG; Address (NLESS)
Before Instruction
PC W
Before Instruction
PC WREG Address (HERE) ?
After Instruction
If REG PC If REG PC
After Instruction
If REG PC If REG PC > = = WREG; Address (GREATER) WREG; Address (NGREATER)
=
2001 Microchip Technology Inc.
DS39026C-page 205
PIC18CXX2
DAW Syntax: Operands: Operation: Decimal Adjust WREG Register [label] DAW None If [WREG<3:0> >9] or [DC = 1] then (WREG<3:0>) + 6 WREG<3:0>; else (WREG<3:0>) WREG<3:0>; If [WREG<7:4> >9] or [C = 1] then (WREG<7:4>) + 6 WREG<7:4>; else (WREG<7:4>) WREG<7:4>; Status Affected: Encoding: Description: C
0000 0000 0000 0111
DECF Syntax: Operands:
Decrement f [ label ] DECF f [,d [,a] 0 f 255 d [0,1] a [0,1] (f) - 1 dest C,DC,N,OV,Z
0000 01da ffff ffff
Operation: Status Affected: Encoding: Description:
DAW adjusts the eight-bit value in WREG, resulting from the earlier addition of two variables (each in packed BCD format) and produces a correct packed BCD result. 1 1 Q2
Read register WREG
DAW
Decrement register 'f'. If 'd' is 0, the result is stored in WREG. If 'd' is 1, the result is stored back in register 'f' (default). If 'a' is 0, the Access Bank will be selected, overriding the BSR value. If 'a' = 1, then the bank will be selected as per the BSR value (default). 1 1 Q2
Read register 'f'
DECF = = = = 0x01 0 0x00 1
Words: Cycles: Q Cycle Activity: Q1
Decode
Words: Cycles: Q Cycle Activity: Q1
Decode
Q3
Process Data
CNT, 1, 0
Q4
Write to destination
Q3
Process Data
Q4
Write WREG
Example:
CNT Z CNT Z
Before Instruction
Example1:
WREG C DC WREG C DC = = = = = =
Before Instruction
0xA5 0 0 0x05 1 0
After Instruction
After Instruction
Example 2: Before Instruction
WREG C DC WREG C DC = = = = = = 0xCE 0 0 0x34 1 0
After Instruction
DS39026C-page 206
2001 Microchip Technology Inc.
PIC18CXX2
DECFSZ Syntax: Operands: Decrement f, skip if 0 [ label ] DECFSZ f [,d [,a]] 0 f 255 d [0,1] a [0,1] (f) - 1 dest, skip if result = 0 None
0010 11da ffff ffff
DCFSNZ Syntax: Operands:
Decrement f, skip if not 0 [label] DCFSNZ 0 f 255 d [0,1] a [0,1] (f) - 1 dest, skip if result 0 None
0100 11da ffff ffff
f [,d [,a]
Operation: Status Affected: Encoding: Description:
Operation: Status Affected: Encoding: Description:
The contents of register 'f' are decremented. If 'd' is 0, the result is placed in WREG. If 'd' is 1, the result is placed back in register 'f' (default). If the result is 0, the next instruction, which is already fetched, is discarded and a NOP is executed instead, making it a two-cycle instruction. If 'a' is 0, the Access Bank will be selected, overriding the BSR value. If 'a' = 1, then the bank will be selected as per the BSR value (default). 1 1(2) Note: 3 cycles if skip and followed by a 2-word instruction. Q2
Read register 'f'
The contents of register 'f' are decremented. If 'd' is 0, the result is placed in WREG. If 'd' is 1, the result is placed back in register 'f' (default). If the result is not 0, the next instruction, which is already fetched, is discarded and a NOP is executed instead, making it a twocycle instruction. If 'a' is 0, the Access Bank will be selected, overriding the BSR value. If 'a' = 1, then the bank will be selected as per the BSR value (default). 1 1(2) Note: 3 cycles if skip and followed by a 2-word instruction. Q2
Read register 'f'
Words: Cycles:
Words: Cycles:
Q Cycle Activity: Q1
Decode
Q3
Process Data
Q4
Write to destination
Q Cycle Activity: Q1
Decode
Q3
Process Data
Q4
Write to destination
If skip: Q1
No operation
If skip: Q2
No operation
Q3
No operation
Q4
No operation
Q1
No operation
Q2
No operation
Q3
No operation
Q4
No operation
If skip and followed by 2-word instruction: Q1 Q2 Q3
No operation No operation No operation No operation
HERE CONTINUE
Q4
No operation No operation
CNT, 1, 1 LOOP
If skip and followed by 2-word instruction: Q1 Q2 Q3
No operation No operation No operation No operation
HERE ZERO NZERO = = = = =
Q4
No operation No operation
No operation No operation
DECFSZ GOTO
No operation No operation
DCFSNZ : : ?
Example:
Example:
TEMP, 1, 0
Before Instruction
PC CNT If CNT PC If CNT PC = = = = = Address (HERE) CNT - 1 0; Address (CONTINUE) 0; Address (HERE+2)
Before Instruction
TEMP
After Instruction
After Instruction
TEMP If TEMP PC If TEMP PC TEMP - 1, 0; Address (ZERO) 0; Address (NZERO)
2001 Microchip Technology Inc.
DS39026C-page 207
PIC18CXX2
GOTO Syntax: Operands: Operation: Status Affected: Encoding: 1st word (k<7:0>) 2nd word(k<19:8>) Description: Unconditional Branch [ label ] GOTO k 0 k 1048575 k PC<20:1> None
1110 1111 1111 k19kkk k7kkk kkkk kkkk0 kkkk8
INCF Syntax: Operands:
Increment f [ label ] INCF f [,d [,a] 0 f 255 d [0,1] a [0,1] (f) + 1 dest C,DC,N,OV,Z
0010 10da ffff ffff
Operation: Status Affected: Encoding: Description:
GOTO allows an unconditional branch anywhere within entire 2 Mbyte memory range. The 20-bit value 'k' is loaded into PC<20:1>. GOTO is always a two-cycle instruction. 2 2
Words: Cycles: Q Cycle Activity: Q1
Decode
The contents of register 'f' are incremented. If 'd' is 0, the result is placed in WREG. If 'd' is 1, the result is placed back in register 'f' (default). If 'a' is 0, the Access Bank will be selected, overriding the BSR value. If 'a' = 1, then the bank will be selected as per the BSR value (default). 1 1 Q2
Read register 'f'
INCF
Words: Q2
Read literal 'k'<7:0>, No operation
Q3
No operation No operation
Q4
Read literal 'k'<19:8>, Write to PC No operation
Cycles: Q Cycle Activity: Q1
Decode
Q3
Process Data
CNT, 1, 0
Q4
Write to destination
No operation
Example:
PC =
GOTO THERE
Example:
CNT Z C DC CNT Z C DC = = = = = = = =
After Instruction
Address (THERE)
Before Instruction
0xFF 0 ? ? 0x00 1 1 1
After Instruction
DS39026C-page 208
2001 Microchip Technology Inc.
PIC18CXX2
INCFSZ Syntax: Operands: Increment f, skip if 0 [ label ] INCFSZ f [,d [,a] 0 f 255 d [0,1] a [0,1] (f) + 1 dest, skip if result = 0 None
0011 11da ffff ffff
INFSNZ Syntax: Operands:
Increment f, skip if not 0 [label] INFSNZ f [,d [,a] 0 f 255 d [0,1] a [0,1] (f) + 1 dest, skip if result 0 None
0100 10da ffff ffff
Operation: Status Affected: Encoding: Description:
Operation: Status Affected: Encoding: Description:
The contents of register 'f' are incremented. If 'd' is 0, the result is placed in WREG. If 'd' is 1, the result is placed back in register 'f' (default). If the result is 0, the next instruction, which is already fetched, is discarded and a NOP is executed instead, making it a two-cycle instruction. If 'a' is 0, the Access Bank will be selected, overriding the BSR value. If 'a' = 1, then the bank will be selected as per the BSR value (default). 1 1(2) Note: 3 cycles if skip and followed by a 2-word instruction. Q2
Read register 'f'
The contents of register 'f' are incremented. If 'd' is 0, the result is placed in WREG. If 'd' is 1, the result is placed back in register 'f' (default). If the result is not 0, the next instruction, which is already fetched, is discarded and a NOP is executed instead, making it a twocycle instruction. If 'a' is 0, the Access Bank will be selected, overriding the BSR value. If 'a' = 1, then the bank will be selected as per the BSR value (default). 1 1(2) Note: 3 cycles if skip and followed by a 2-word instruction. Q2
Read register 'f'
Words: Cycles:
Words: Cycles:
Q Cycle Activity: Q1
Decode
Q3
Process Data
Q4
Write to destination
Q Cycle Activity: Q1
Decode
Q3
Process Data
Q4
Write to destination
If skip: Q1
No operation
If skip: Q2
No operation
Q3
No operation
Q4
No operation
Q1
No operation
Q2
No operation
Q3
No operation
Q4
No operation
If skip and followed by 2-word instruction: Q1 Q2 Q3
No operation No operation No operation No operation
HERE NZERO ZERO = = = = =
Q4
No operation No operation
If skip and followed by 2-word instruction: Q1 Q2 Q3
No operation No operation No operation No operation
HERE ZERO NZERO = =
Q4
No operation No operation
No operation No operation
INCFSZ : :
No operation No operation
INFSNZ
Example:
CNT, 1, 0
Example:
REG, 1, 0
Before Instruction
PC CNT If CNT PC If CNT PC Address (HERE) CNT + 1 0; Address(ZERO) 0; Address(NZERO)
Before Instruction
PC REG If REG PC If REG PC Address (HERE) REG + 1 0; Address (NZERO) 0; Address (ZERO)
After Instruction
After Instruction
= = =
2001 Microchip Technology Inc.
DS39026C-page 209
PIC18CXX2
IORLW Syntax: Operands: Operation: Status Affected: Encoding: Description: Inclusive OR literal with WREG [ label ] IORLW k 0 k 255 (WREG) .OR. k WREG N,Z
0000 1001 kkkk kkkk
IORWF Syntax: Operands:
Inclusive OR WREG with f [ label ] IORWF f [,d [,a] 0 f 255 d [0,1] a [0,1] (WREG) .OR. (f) dest N,Z
0001 00da ffff ffff
Operation: Status Affected: Encoding: Description:
The contents of WREG are OR'ed with the eight-bit literal 'k'. The result is placed in WREG. 1 1 Q2
Read literal 'k'
IORLW
Words: Cycles: Q Cycle Activity: Q1
Decode
Q3
Process Data
0x35
Q4
Write to WREG
Inclusive OR WREG with register 'f'. If 'd' is 0, the result is placed in WREG. If 'd' is 1, the result is placed back in register 'f' (default). If 'a' is 0, the Access Bank will be selected, overriding the BSR value. If 'a' = 1, then the bank will be selected as per the BSR value (default). 1 1 Q2
Read register 'f'
IORWF
Example:
WREG =
Words: Cycles: Q Cycle Activity: Q1
Decode
Before Instruction
0x9A
After Instruction
WREG = 0xBF
Q3
Process Data
RESULT, 0, 1
Q4
Write to destination
Example:
RESULT = WREG =
Before Instruction
0x13 0x91 0x13 0x93
After Instruction
RESULT = WREG =
DS39026C-page 210
2001 Microchip Technology Inc.
PIC18CXX2
LFSR Syntax: Operands: Operation: Status Affected: Encoding: Description: Load FSR [ label ] LFSR f,k 0f2 0 k 4095 k FSRf None
1110 1111 1110 0000 00ff k7kkk k11kkk kkkk
MOVF Syntax: Operands:
Move f [ label ] MOVF f [,d [,a] 0 f 255 d [0,1] a [0,1] f dest N,Z
0101 00da ffff ffff
Operation: Status Affected: Encoding: Description:
The 12-bit literal 'k' is loaded into the file select register pointed to by 'f'. 2 2 Q2
Read literal 'k' MSB
Words: Cycles: Q Cycle Activity: Q1
Decode
Q3
Process Data
Q4
Write literal 'k' MSB to FSRfH Write literal 'k' to FSRfL
The contents of register 'f' are moved to a destination dependent upon the status of 'd'. If 'd' is 0, the result is placed in WREG. If 'd' is 1, the result is placed back in register 'f' (default). Location 'f' can be anywhere in the 256 byte bank. If 'a' is 0, the Access Bank will be selected, overriding the BSR value. If `a' = 1, then the bank will be selected as per the BSR value (default). 1 1 Q2
Read register 'f'
MOVF
Decode
Read literal 'k' LSB
Process Data
Words: Cycles: Q Cycle Activity: Q1
Decode
Example:
FSR2H FSR2L
LFSR 2, 0x3AB = = 0x03 0xAB
After Instruction
Q3
Process Data
REG, 0, 0
Q4
Write WREG
Example:
REG WREG
Before Instruction
= = = = 0x22 0xFF 0x22 0x22
After Instruction
REG WREG
2001 Microchip Technology Inc.
DS39026C-page 211
PIC18CXX2
MOVFF Syntax: Operands: Operation: Status Affected: Encoding: 1st word (source) 2nd word (destin.) Description: Move f to f [label] MOVFF fs,fd 0 fs 4095 0 fd 4095 (fs) fd None
1100 1111 ffff ffff ffff ffff ffffs ffffd
MOVLB Syntax: Operands: Operation: Status Affected: Encoding: Description: Words: Cycles: Q Cycle Activity: Q1
Decode
Move literal to low nibble in BSR [ label ] k BSR None
0000 0001 kkkk kkkk
MOVLB k
0 k 255
The 8-bit literal 'k' is loaded into the Bank Select Register (BSR). 1 1 Q2
Read literal 'k'
The contents of source register 'fs' are moved to destination register 'fd'. Location of source 'fs' can be anywhere in the 4096 byte data space (000h to FFFh), and location of destination 'fd' can also be anywhere from 000h to FFFh. Either source or destination can be WREG (a useful special situation). MOVFF is particularly useful for transferring a data memory location to a peripheral register (such as the transmit buffer or an I/O port). The MOVFF instruction cannot use the PCL, TOSU, TOSH or TOSL as the destination register.
Q3
Process Data
Q4
Write literal 'k' to BSR
Example:
MOVLB = =
5 0x02 0x05
Before Instruction
BSR register
After Instruction
BSR register
Words: Cycles: Q Cycle Activity: Q1
Decode
2 2 (3) Q2
Read register 'f' (src) No operation No dummy read
Q3
Process Data No operation
Q4
No operation Write register 'f' (dest)
Decode
Example:
REG1 REG2
MOVFF
REG1, REG2
Before Instruction
= = = = 0x33 0x11 0x33, 0x33
After Instruction
REG1 REG2
DS39026C-page 212
2001 Microchip Technology Inc.
PIC18CXX2
MOVLW Syntax: Operands: Operation: Status Affected: Encoding: Description: Words: Cycles: Q Cycle Activity: Q1
Decode
Move literal to WREG [ label ] MOVLW k 0 k 255 k WREG None
0000 1110 kkkk kkkk
MOVWF Syntax: Operands: Operation: Status Affected: Encoding: Description:
Move WREG to f [ label ] MOVWF f [,a] 0 f 255 a [0,1] (WREG) f None
0110 111a ffff ffff
The eight-bit literal 'k' is loaded into WREG. 1 1 Q2
Read literal 'k'
MOVLW
Q3
Process Data
0x5A
Q4
Write to WREG
Move data from WREG to register 'f'. Location 'f' can be anywhere in the 256 byte bank. If `a' is 0, the Access Bank will be selected, overriding the BSR value. If `a' = 1, then the bank will be selected as per the BSR value (default). 1 1 Q2
Read register 'f'
MOVWF
Words: Cycles: Q Cycle Activity: Q1
Decode
Example:
WREG =
After Instruction
0x5A
Q3
Process Data
REG, 0
Q4
Write register 'f'
Example:
WREG REG WREG REG = = = =
Before Instruction
0x4F 0xFF 0x4F 0x4F
After Instruction
2001 Microchip Technology Inc.
DS39026C-page 213
PIC18CXX2
MULLW Syntax: Operands: Operation: Status Affected: Encoding: Description: Multiply Literal with WREG [ label ] MULLW k 0 k 255 (WREG) x k PRODH:PRODL None
0000 1101 kkkk kkkk
MULWF Syntax: Operands: Operation: Status Affected: Encoding: Description:
Multiply WREG with f [ label ] MULWF f [,a] 0 f 255 a [0,1] (WREG) x (f) PRODH:PRODL None
0000 001a ffff ffff
An unsigned multiplication is carried out between the contents of WREG and the 8-bit literal 'k'. The 16-bit result is placed in PRODH:PRODL register pair. PRODH contains the high byte. WREG is unchanged. None of the status flags are affected. Note that neither overflow, nor carry is possible in this operation. A zero result is possible but not detected. 1 1 Q2
Read literal 'k'
Words: Cycles: Q Cycle Activity: Q1
Decode
Q3
Process Data
Q4
Write registers PRODH: PRODL
An unsigned multiplication is carried out between the contents of WREG and the register file location 'f'. The 16-bit result is stored in the PRODH:PRODL register pair. PRODH contains the high byte. Both WREG and 'f' are unchanged. None of the status flags are affected. Note that neither overflow, nor carry is possible in this operation. A zero result is possible but not detected. If `a' is 0, the Access Bank will be selected, overriding the BSR value. If `a'= 1, then the bank will be selected as per the BSR value (default). 1 1 Q2
Read register 'f'
Words: Cycles: Q Cycle Activity: Q1
Decode
Example:
WREG PRODH PRODL
MULLW
0xC4
Before Instruction
= = = = = = 0xE2 ? ? 0xE2 0xAD 0x08
Q3
Process Data
Q4
Write registers PRODH: PRODL
After Instruction
WREG PRODH PRODL
Example:
WREG REG PRODH PRODL
MULWF
REG, 1
Before Instruction
= = = = = = = = 0xC4 0xB5 ? ? 0xC4 0xB5 0x8A 0x94
After Instruction
WREG REG PRODH PRODL
DS39026C-page 214
2001 Microchip Technology Inc.
PIC18CXX2
NEGF Syntax: Operands: Operation: Status Affected: Encoding: Description: Negate f [label] NEGF f [,a] 0 f 255 a [0,1] (f)+1f N,OV, C, DC, Z
0110 110a ffff ffff
NOP Syntax: Operands: Operation: Status Affected: Encoding: Description: Words: Cycles: Q Cycle Activity: Q1
Decode
No Operation [ label ] None No operation None
0000 1111 0000 xxxx 0000 xxxx 0000 xxxx
NOP
Location `f' is negated using two's complement. The result is placed in the data memory location 'f'. If 'a' is 0, the Access Bank will be selected, overriding the BSR value. If 'a' = 1, then the bank will be selected as per the BSR value. 1 1 Q2
Read register 'f'
NEGF
No operation. 1 1 Q2
No operation
Q3
No operation
Q4
No operation
Words: Cycles: Q Cycle Activity: Q1
Decode
Example: Q3
Process Data
REG, 1
Q4
Write register 'f'
None.
Example:
REG REG = =
Before Instruction
0011 1010 [0x3A] 1100 0110 [0xC6]
After Instruction
2001 Microchip Technology Inc.
DS39026C-page 215
PIC18CXX2
POP Syntax: Operands: Operation: Status Affected: Encoding: Description: Pop Top of Return Stack [ label ] None (TOS) bit bucket None
0000 0000 0000 0110
PUSH Syntax: Operands: Operation: Status Affected: Encoding: Description:
Push Top of Return Stack [ label ] None (PC+2) TOS None
0000 0000 0000 0101
POP
PUSH
The TOS value is pulled off the return stack and is discarded. The TOS value then becomes the previous value that was pushed onto the return stack. This instruction is provided to enable the user to properly manage the return stack to incorporate a software stack. 1 1 Q2
No operation
POP GOTO
The PC+2 is pushed onto the top of the return stack. The previous TOS value is pushed down on the stack. This instruction allows to implement a software stack by modifying TOS, and then push it onto the return stack. 1 1 Q2
PUSH PC+2 onto return stack
PUSH
Words: Cycles: Q Cycle Activity: Q1
Decode
Words: Cycles: Q Cycle Activity: Q1
Decode
Q3
No operation
Q4
No operation
Q3
POP TOS value
Q4
No operation
Example: Example:
NEW TOS PC
Before Instruction
= = 00345Ah 000124h
Before Instruction
TOS = 0031A2h Stack (1 level down)= 014332h
After Instruction
PC TOS Stack (1 level down) = = = 000126h 000126h 00345Ah
After Instruction
TOS PC = 014332h = NEW
DS39026C-page 216
2001 Microchip Technology Inc.
PIC18CXX2
RCALL Syntax: Operands: Operation: Status Affected: Encoding: Description: Relative Call [ label ] RCALL -1024 n 1023 (PC) + 2 TOS, (PC) + 2 + 2n PC None
1101 1nnn nnnn nnnn
RESET n Syntax: Operands: Operation: Status Affected: Encoding: Description: Words: Cycles: Q Cycle Activity: Q1
Decode
Reset [ label ] None Reset all registers and flags that are affected by a MCLR reset. All
0000 0000 1111 1111
RESET
Subroutine call with a jump up to 1K from the current location. First, return address (PC+2) is pushed onto the stack. Then, add the 2's complement number '2n' to the PC. Since the PC will have incremented to fetch the next instruction, the new address will be PC+2+2n. This instruction is a two-cycle instruction. 1 2 Q2
Read literal 'n' Push PC to stack
This instruction provides a way to execute a MCLR Reset in software. 1 1 Q2
Start reset
RESET
Q3
No operation
Q4
No operation
Words: Cycles: Q Cycle Activity: Q1
Decode
Example:
After Instruction Q3
Process Data
Q4
Write to PC
Registers Flags*
= =
Reset Value Reset Value
No operation
No operation
HERE
No operation
RCALL Jump
No operation
Example:
PC =
Before Instruction
Address(HERE) Address(Jump) Address (HERE+2)
After Instruction
PC = TOS =
2001 Microchip Technology Inc.
DS39026C-page 217
PIC18CXX2
RETFIE Syntax: Operands: Operation: Return from Interrupt [ label ] s [0,1] (TOS) PC, 1 GIE/GIEH or PEIE/GIEL, if s = 1 (WS) WREG, (STATUSS) STATUS, (BSRS) BSR, PCLATU, PCLATH are unchanged. GIE/GIEH,PEIE/GIEL.
0000 0000 0001 000s
RETLW Syntax: Operands: Operation:
Return Literal to WREG [ label ] RETLW k 0 k 255 k WREG, (TOS) PC, PCLATU, PCLATH are unchanged None
0000 1100 kkkk kkkk
RETFIE [s]
Status Affected: Encoding: Description:
Status Affected: Encoding: Description:
Return from Interrupt. Stack is popped and Top-of-Stack (TOS) is loaded into the PC. Interrupts are enabled by setting either the high or low priority global interrupt enable bit. If `s' = 1, the contents of the shadow registers WS, STATUSS and BSRS are loaded into their corresponding registers, WREG, STATUS and BSR. If `s' = 0, no update of these registers occurs (default). 1 2 Q2
No operation
WREG is loaded with the eight-bit literal 'k'. The program counter is loaded from the top of the stack (the return address). The high address latch (PCLATH) remains unchanged. 1 2 Q2
Read literal 'k' No operation
Words: Cycles: Q Cycle Activity: Q1
Decode
Q3
Process Data No operation
Q4
pop PC from stack, Write to WREG No operation
No operation
Words: Cycles: Q Cycle Activity: Q1
Decode
Example:
CALL TABLE
Q3
No operation
Q4
pop PC from stack Set GIEH or GIEL
: TABLE ADDWF RETLW RETLW : : RETLW
; ; ; ;
WREG contains table offset value WREG now has table value
No operation
No operation
RETFIE 1
No operation
No operation
PCL k0 k1
; WREG = offset ; Begin table ;
Example: After Interrupt
kn
; End of table
PC = W = BSR = STATUS = GIE/GIEH, PEIE/GIEL=
TOS WS BSRS STATUSS 1
Before Instruction
WREG = 0x07
After Instruction
WREG = value of kn
DS39026C-page 218
2001 Microchip Technology Inc.
PIC18CXX2
RETURN Syntax: Operands: Operation: Return from Subroutine [ label ] s [0,1] (TOS) PC, if s = 1 (WS) WREG, (STATUSS) STATUS, (BSRS) BSR, PCLATU, PCLATH are unchanged None
0000 0000 0001 001s
RLCF Syntax: Operands:
Rotate Left f through Carry [ label ] RLCF f [,d [,a] 0 f 255 d [0,1] a [0,1] (f) dest, (f<7>) C, (C) dest<0> C,N,Z
0011 01da ffff ffff
RETURN [s]
Operation:
Status Affected: Encoding: Description:
Status Affected: Encoding: Description:
Return from subroutine. The stack is popped and the top of the stack (TOS) is loaded into the program counter. If `s'= 1, the contents of the shadow registers WS, STATUSS and BSRS are loaded into their corresponding registers, WREG, STATUS and BSR. If `s' = 0, no update of these registers occurs (default). 1 2 Q2
No operation No operation
The contents of register 'f' are rotated one bit to the left through the Carry Flag. If 'd' is 0, the result is placed in WREG. If 'd' is 1, the result is stored back in register 'f' (default). If `a' is 0, the Access Bank will be selected, overriding the BSR value. If 'a' = 1, then the bank will be selected as per the BSR value (default). C
register f
Words: Cycles: Q Cycle Activity: Q1
Decode No operation
Words: Cycles: Q3
Process Data No operation
1 1 Q2
Read register 'f'
RLCF
Q4
pop PC from stack No operation
Q Cycle Activity: Q1
Decode
Q3
Process Data
Q4
Write to destination
Example: Example: After Interrupt
PC = TOS RETURN REG C REG WREG C = = = = =
REG, 0, 0
Before Instruction
1110 0110 0 1110 0110 1100 1100 1
After Instruction
2001 Microchip Technology Inc.
DS39026C-page 219
PIC18CXX2
RLNCF Syntax: Operands: Rotate Left f (no carry) [ label ] RLNCF f [,d [,a] 0 f 255 d [0,1] a [0,1] (f) dest, (f<7>) dest<0> N,Z
0100 01da ffff ffff
RRCF Syntax: Operands:
Rotate Right f through Carry [ label ] RRCF f [,d [,a] 0 f 255 d [0,1] a [0,1] (f) dest, (f<0>) C, (C) dest<7> C,N,Z
0011 00da ffff ffff
Operation: Status Affected: Encoding: Description:
Operation:
Status Affected: Encoding: Description:
The contents of register 'f' are rotated one bit to the left. If 'd' is 0, the result is placed in WREG. If 'd' is 1, the result is stored back in register 'f' (default). If 'a' is 0, the Access Bank will be selected, overriding the BSR value. If 'a' is 1, then the bank will be selected as per the BSR value (default).
register f
The contents of register 'f' are rotated one bit to the right through the Carry Flag. If 'd' is 0, the result is placed in WREG. If 'd' is 1, the result is placed back in register 'f' (default). If `a' is 0, the Access Bank will be selected, overriding the BSR value. If 'a' is 1, then the bank will be selected as per the BSR value (default). C
register f
Words: Cycles: Q Cycle Activity: Q1
Decode
1 1 Words: Q2
Read register 'f'
RLNCF = =
1 1 Q2
Read register 'f'
RRCF
Q3
Process Data
Q4
Write to destination
Cycles: Q Cycle Activity: Q1
Decode
Q3
Process Data
REG, 0, 0
Q4
Write to destination
Example:
REG REG
REG, 1, 0
Before Instruction
1010 1011 0101 0111
Example:
REG C REG WREG C = = = = =
After Instruction
Before Instruction
1110 0110 0 1110 0110 0111 0011 0
After Instruction
DS39026C-page 220
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PIC18CXX2
RRNCF Syntax: Operands: Rotate Right f (no carry) [ label ] RRNCF f [,d [,a] 0 f 255 d [0,1] a [0,1] (f) dest, (f<0>) dest<7> N,Z
0100 00da ffff ffff
SETF Syntax: Operands: Operation: Status Affected: Encoding: Description:
Set f [label] SETF 0 f 255 a [0,1] FFh f None
0110 100a ffff ffff
f [,a]
Operation: Status Affected: Encoding: Description:
The contents of register 'f' are rotated one bit to the right. If 'd' is 0, the result is placed in WREG. If 'd' is 1, the result is placed back in register 'f' (default). If 'a' is 0, the Access Bank will be selected, overriding the BSR value. If 'a' is 1, then the bank will be selected as per the BSR value (default).
register f
The contents of the specified register are set to FFh. If 'a' is 0, the Access Bank will be selected, overriding the BSR value. If 'a' is 1, then the bank will be selected as per the BSR value (default). 1 1 Q2
Read register 'f'
SETF = = 0x5A 0xFF
Words: Cycles: Q Cycle Activity: Q1
Decode
Q3
Process Data
REG,1
Q4
Write register 'f'
Words: Cycles: Q Cycle Activity: Q1
Decode
1 1 Q2
Read register 'f'
RRNCF = =
Example: Q3
Process Data
REG, 1, 0
Before Instruction Q4
Write to destination
REG
After Instruction
REG
Example 1:
REG REG
Before Instruction
1101 0111 1110 1011 RRNCF REG, 0, 0
After Instruction
Example 2:
WREG REG WREG REG = = = =
Before Instruction
? 1101 0111 1110 1011 1101 0111
After Instruction
2001 Microchip Technology Inc.
DS39026C-page 221
PIC18CXX2
SLEEP Syntax: Operands: Operation: Enter SLEEP mode [ label ] SLEEP None 00h WDT, 0 WDT postscaler, 1 TO, 0 PD TO, PD
0000 0000 0000 0011
SUBFWB Syntax: Operands:
Subtract f from WREG with borrow [ label ] SUBFWB 0 f 255 d [0,1] a [0,1] (WREG) - (f) - (C) dest N,OV, C, DC, Z
0101 01da ffff ffff
f [,d [,a]
Operation: Status Affected: Encoding: Description:
Status Affected: Encoding: Description:
The power-down status bit (PD) is cleared. The time-out status bit (TO) is set. Watchdog Timer and its postscaler are cleared. The processor is put into SLEEP mode with the oscillator stopped. 1 1 Q2
No operation
SLEEP
Words: Cycles: Q Cycle Activity: Q1
Decode
Subtract register 'f' and carry flag (borrow) from WREG (2's complement method). If 'd' is 0, the result is stored in WREG. If 'd' is 1, the result is stored in register 'f' (default). If 'a' is 0, the Access Bank will be selected, overriding the BSR value. If 'a' is 1, then the bank will be selected as per the BSR value (default). 1 1 Q2
Read register 'f'
SUBFWB = = = = = = = = 3 2 1 FF 2 0 0 1 SUBFWB
Words: Cycles: Q3
Process Data
Q4
Go to sleep
Q Cycle Activity: Q1
Decode
Q3
Process Data
REG, 1, 0
Q4
Write to destination
Example:
TO PD TO PD = = = = ? ?
Before Instruction
Example 1:
REG WREG C REG WREG C Z N
Before Instruction
After Instruction
1 0
After Instruction
If WDT causes wake-up, this bit is cleared.
; result is negative REG, 0, 0
Example 2:
REG WREG C REG WREG C Z N = = = = = = = =
Before Instruction
2 5 1 2 3 1 0 0 SUBFWB
After Instruction
; result is positive REG, 1, 0
Example 3:
REG WREG C REG WREG C Z N = = = = = = = =
Before Instruction
1 2 0 0 2 1 1 0
After Instruction
; result is zero
DS39026C-page 222
2001 Microchip Technology Inc.
PIC18CXX2
SUBLW Syntax: Operands: Operation: Status Affected: Encoding: Description: Subtract WREG from literal [ label ] SUBLW k 0 k 255 k - (WREG) WREG N,OV, C, DC, Z
0000 1000 kkkk kkkk
SUBWF Syntax: Operands:
Subtract WREG from f [ label ] SUBWF 0 f 255 d [0,1] a [0,1] (f) - (WREG) dest N,OV, C, DC, Z
0101 11da ffff ffff
f [,d [,a]
Operation: Status Affected: Encoding: Description:
WREG is subtracted from the eight-bit literal 'k'. The result is placed in WREG. 1 1 Q2
Read literal 'k'
SUBLW
Words: Cycles: Q Cycle Activity: Q1
Decode
Q3
Process Data
0x02
Q4
Write to WREG
Subtract WREG from register 'f' (2's complement method). If 'd' is 0, the result is stored in WREG. If 'd' is 1, the result is stored back in register 'f' (default). If 'a' is 0, the Access Bank will be selected, overriding the BSR value. If 'a' is 1, then the bank will be selected as per the BSR value (default). 1 1 Q2
Read register 'f'
SUBWF
Example 1:
WREG C WREG C Z N = = = = = =
Words: Cycles: Q Cycle Activity: Q1
Decode
Before Instruction
1 ? 1 1 0 0 SUBLW
After Instruction
; result is positive
Q3
Process Data
REG, 1, 0
Q4
Write to destination
Example 1:
0x02 REG WREG C REG WREG C Z N = = = = = = = =
Before Instruction Example 2:
WREG C WREG C Z N = = = = = =
Before Instruction
2 ? 0 1 1 0 SUBLW
3 2 ? 1 2 1 0 0 SUBWF
After Instruction
After Instruction
; result is zero
; result is positive
Example 2:
0x02 REG WREG C REG WREG C Z N = = = = = = = =
REG, 0, 0
Example 3:
WREG C WREG C Z N = = = = = =
Before Instruction
2 2 ? 2 0 1 1 0 SUBWF = = = = = = = = 1 2 ? FFh 2 0 0 1 ;(2's complement) ; result is negative
Before Instruction
3 ? FF 0 0 1 ; (2's complement) ; result is negative
After Instruction
After Instruction
; result is zero
Example 3:
REG WREG C REG WREG C Z N
REG, 1, 0
Before Instruction
After Instruction
2001 Microchip Technology Inc.
DS39026C-page 223
PIC18CXX2
SUBWFB Syntax: Operands: Subtract WREG from f with Borrow [ label ] SUBWFB 0 f 255 d [0,1] a [0,1] (f) - (WREG) - (C) dest N,OV, C, DC, Z
0101 10da ffff ffff
SWAPF Syntax: Operands:
Swap f [ label ] SWAPF f [,d [,a] 0 f 255 d [0,1] a [0,1] (f<3:0>) dest<7:4>, (f<7:4>) dest<3:0> None
0011 10da ffff ffff
f [,d [,a]
Operation: Status Affected: Encoding: Description:
Operation: Status Affected: Encoding: Description:
Subtract WREG and the carry flag (borrow) from register 'f' (2's complement method). If 'd' is 0, the result is stored in WREG. If 'd' is 1, the result is stored back in register 'f' (default). If 'a' is 0, the Access Bank will be selected, overriding the BSR value. If 'a' is 1, then the bank will be selected as per the BSR value (default). 1 1 Q2
Read register 'f'
SUBWFB
Words: Cycles: Q Cycle Activity: Q1
Decode
The upper and lower nibbles of register 'f' are exchanged. If 'd' is 0, the result is placed in WREG. If 'd' is 1, the result is placed in register 'f' (default). If 'a' is 0, the Access Bank will be selected, overriding the BSR value. If 'a' is 1, then the bank will be selected as per the BSR value (default). 1 1 Q2
Read register 'f'
SWAPF
Words: Cycles: Q3
Process Data
REG, 1, 0
Q4
Write to destination
Q Cycle Activity: Q1
Decode
Q3
Process Data
REG, 1, 0
Q4
Write to destination
Example 1:
REG WREG C REG WREG C Z N = = = = = = = =
Before Instruction
0x19 0x0D 1 0x0C 0x0D 1 0 0 (0001 1001) (0000 1101)
Example:
REG = =
Before Instruction
0x53 0x35
After Instruction
(0000 1011) (0000 1101) ; result is positive
After Instruction
REG
Example 2:
REG WREG C REG WREG C Z N = = = = = = = =
SUBWFB REG, 0, 0 0x1B 0x1A 0 0x1B 0x00 1 1 0 SUBWFB = = = = = = = = 0x03 0x0E 1 0xF5 0x0E 0 0 1 (0001 1011) (0001 1010)
Before Instruction
After Instruction
(0001 1011)
; result is zero REG, 1, 0 (0000 0011) (0000 1101)
Example 3:
REG WREG C REG WREG C Z N
Before Instruction
After Instruction
(1111 0100) ; [2's comp] (0000 1101) ; result is negative
DS39026C-page 224
2001 Microchip Technology Inc.
PIC18CXX2
TBLRD Syntax: Operands: Operation: Table Read [ label ] None if TBLRD *, (Prog Mem (TBLPTR)) TABLAT; TBLPTR - No Change; if TBLRD *+, (Prog Mem (TBLPTR)) TABLAT; (TBLPTR) +1 TBLPTR; if TBLRD *-, (Prog Mem (TBLPTR)) TABLAT; (TBLPTR) -1 TBLPTR; if TBLRD +*, (TBLPTR) +1 TBLPTR; (Prog Mem (TBLPTR)) TABLAT; None
0000 0000 0000 10nn nn=0 * =1 *+ =2 *=3 +*
TBLRD Example 1:
Table Read (cont'd)
TBLRD *+ ;
TBLRD ( *; *+; *-; +*)
Before Instruction
TABLAT TBLPTR MEMORY(0x00A356) = = = = = TBLRD +* ; 0x55 0x00A356 0x34 0x34 0x00A357
After Instruction
TABLAT TBLPTR
Example 2:
Before Instruction
TABLAT TBLPTR MEMORY(0x01A357) MEMORY(0x01A358) = = = = = = 0xAA 0x01A357 0x12 0x34 0x34 0x01A358
After Instruction
TABLAT TBLPTR
Status Affected: Encoding:
Description:
This instruction is used to read the contents of Program Memory (P.M.). To address the program memory, a pointer called Table Pointer (TBLPTR) is used. The TBLPTR (a 21-bit pointer) points to each byte in the program memory. TBLPTR has a 2 Mbyte address range. TBLPTR[0] = 0: Least Significant Byte of Program Memory Word TBLPTR[0] = 1: Most Significant Byte of Program Memory Word The TBLRD instruction can modify the value of TBLPTR as follows: * no change * post-increment * post-decrement * pre-increment
Words: Cycles: Q Cycle Activity: Q1
Decode No operation
1 2 Q2
No operation No operation (Read Program Memory)
Q3
No operation No operation
Q4
No operation No operation (Write TABLAT)
2001 Microchip Technology Inc.
DS39026C-page 225
PIC18CXX2
TBLWT Syntax: Operands: Operation: Table Write [ label ] None if TBLWT*, (TABLAT) Prog Mem (TBLPTR) or Holding Register; TBLPTR - No Change; if TBLWT*+, (TABLAT) Prog Mem (TBLPTR) or Holding Register; (TBLPTR) +1 TBLPTR; if TBLWT*-, (TABLAT) Prog Mem (TBLPTR) or Holding Register; (TBLPTR) -1 TBLPTR; if TBLWT+*, (TBLPTR) +1 TBLPTR; (TABLAT) Prog Mem (TBLPTR) or Holding Register; None
0000 0000 0000 11nn nn=0 * =1 *+ =2 *=3 +*
TBLWT Example 1:
Table Write (Continued)
TBLWT *+;
TBLWT ( *; *+; *-; +*)
Before Instruction
TABLAT TBLPTR MEMORY(0x00A356) TABLAT TBLPTR MEMORY(0x00A356) = = = = = = +*; 0x55 0x00A356 0xFF 0x55 0x00A357 0x55
After Instructions (table write completion)
Example 2:
TBLWT
Before Instruction
TABLAT TBLPTR MEMORY(0x01389A) MEMORY(0x01389B) TABLAT TBLPTR MEMORY(0x01389A) MEMORY(0x01389B) = = = = = = = = 0x34 0x01389A 0xFF 0xFF 0x34 0x01389B 0xFF 0x34
After Instruction (table write completion)
Status Affected: Encoding:
Description:
This instruction is used to program the contents of Program Memory (P.M.). The TBLPTR (a 21-bit pointer) points to each byte in the program memory. TBLPTR has a 2 Mbyte address range. The LSb of the TBLPTR selects which byte of the program memory location to access. TBLPTR[0] = 0:Least Significant Byte of Program Memory Word TBLPTR[0] = 1:Most Significant Byte of Program Memory Word The TBLWT instruction can modify the value of TBLPTR as follows: * no change * post-increment * post-decrement * pre-increment
Words: Cycles: Q Cycle Activity: Q1
Decode No operation
1 2 (many if long write is to on-chip EPROM program memory) Q2
No operation No operation (Read TABLAT)
Q3
No operation No operation
Q4
No operation No operation (Write to Holding Register or Memory)
DS39026C-page 226
2001 Microchip Technology Inc.
PIC18CXX2
TSTFSZ Syntax: Operands: Operation: Status Affected: Encoding: Description: Test f, skip if 0 [ label ] TSTFSZ f [,a] 0 f 255 a [0,1] skip if f = 0 None
0110 011a ffff ffff
XORLW Syntax: Operands: Operation: Status Affected: Encoding: Description:
Exclusive OR literal with WREG [ label ] XORLW k 0 k 255 (WREG) .XOR. k WREG N,Z
0000 1010 kkkk kkkk
If 'f' = 0, the next instruction, fetched during the current instruction execution, is discarded and a NOP is executed, making this a twocycle instruction. If 'a' is 0, the Access Bank will be selected, overriding the BSR value. If 'a' is 1, then the bank will be selected as per the BSR value (default). 1 1(2) Note: 3 cycles if skip and followed by a 2-word instruction. Q2
Read register 'f'
The contents of WREG are XORed with the 8-bit literal 'k'. The result is placed in WREG. 1 1 Q2
Read literal 'k'
Words: Cycles: Q Cycle Activity: Q1
Decode
Q3
Process Data
Q4
Write to WREG
Words: Cycles:
Example:
WREG =
XORLW 0xAF
0xB5
Before Instruction After Instruction
WREG = 0x1A
Q Cycle Activity: Q1
Decode
Q3
Process Data
Q4
No operation
If skip: Q1
No operation
Q2
No operation
Q3
No operation
Q4
No operation
If skip and followed by 2-word instruction: Q1 Q2 Q3
No operation No operation No operation No operation
HERE NZERO ZERO
Q4
No operation No operation
No operation No operation
TSTFSZ : :
Example:
CNT, 1
Before Instruction
PC = Address(HERE)
After Instruction
If CNT PC If CNT PC = = = 0x00, Address (ZERO) 0x00, Address (NZERO)
2001 Microchip Technology Inc.
DS39026C-page 227
PIC18CXX2
XORWF Syntax: Operands: Exclusive OR WREG with f [ label ] XORWF 0 f 255 d [0,1] a [0,1] (WREG) .XOR. (f) dest N,Z
0001 10da ffff ffff
f [,d [,a]
Operation: Status Affected: Encoding: Description:
Exclusive OR the contents of WREG with register 'f'. If 'd' is 0, the result is stored in WREG. If 'd' is 1, the result is stored back in the register 'f' (default). If `a' is 0, the Access Bank will be selected, overriding the BSR value. If 'a' is 1, then the bank will be selected as per the BSR value (default). 1 1 Q2
Read register 'f'
XORWF
Words: Cycles: Q Cycle Activity: Q1
Decode
Q3
Process Data
REG, 1, 0
Q4
Write to destination
Example:
REG WREG REG WREG = = = =
Before Instruction
0xAF 0xB5 0x1A 0xB5
After Instruction
DS39026C-page 228
2001 Microchip Technology Inc.
PIC18CXX2
20.0 DEVELOPMENT SUPPORT
The MPLAB IDE allows you to: * Edit your source files (either assembly or `C') * One touch assemble (or compile) and download to PICmicro emulator and simulator tools (automatically updates all project information) * Debug using: - source files - absolute listing file - machine code The ability to use MPLAB IDE with multiple debugging tools allows users to easily switch from the costeffective simulator to a full-featured emulator with minimal retraining. The PICmicro(R) microcontrollers are supported with a full range of hardware and software development tools: * Integrated Development Environment - MPLAB(R) IDE Software * Assemblers/Compilers/Linkers - MPASMTM Assembler - MPLAB C17 and MPLAB C18 C Compilers - MPLINKTM Object Linker/ MPLIBTM Object Librarian * Simulators - MPLAB SIM Software Simulator * Emulators - MPLAB ICE 2000 In-Circuit Emulator - ICEPICTM In-Circuit Emulator * In-Circuit Debugger - MPLAB ICD for PIC16F87X * Device Programmers - PRO MATE(R) II Universal Device Programmer - PICSTART(R) Plus Entry-Level Development Programmer * Low Cost Demonstration Boards - PICDEMTM 1 Demonstration Board - PICDEM 2 Demonstration Board - PICDEM 3 Demonstration Board - PICDEM 17 Demonstration Board - KEELOQ(R) Demonstration Board
20.2
MPASM Assembler
The MPASM assembler is a full-featured universal macro assembler for all PICmicro MCU's. The MPASM assembler has a command line interface and a Windows shell. It can be used as a stand-alone application on a Windows 3.x or greater system, or it can be used through MPLAB IDE. The MPASM assembler generates relocatable object files for the MPLINK object linker, Intel(R) standard HEX files, MAP files to detail memory usage and symbol reference, an absolute LST file that contains source lines and generated machine code, and a COD file for debugging. The MPASM assembler features include: * Integration into MPLAB IDE projects. * User-defined macros to streamline assembly code. * Conditional assembly for multi-purpose source files. * Directives that allow complete control over the assembly process.
20.1
MPLAB Integrated Development Environment Software
The MPLAB IDE software brings an ease of software development previously unseen in the 8-bit microcontroller market. The MPLAB IDE is a Windows(R)-based application that contains: * An interface to debugging tools - simulator - programmer (sold separately) - emulator (sold separately) - in-circuit debugger (sold separately) * A full-featured editor * A project manager * Customizable toolbar and key mapping * A status bar * On-line help
20.3
MPLAB C17 and MPLAB C18 C Compilers
The MPLAB C17 and MPLAB C18 Code Development Systems are complete ANSI `C' compilers for Microchip's PIC17CXXX and PIC18CXXX family of microcontrollers, respectively. These compilers provide powerful integration capabilities and ease of use not found with other compilers. For easier source level debugging, the compilers provide symbol information that is compatible with the MPLAB IDE memory display.
2001 Microchip Technology Inc.
DS39026C-page 229
PIC18CXX2
20.4 MPLINK Object Linker/ MPLIB Object Librarian 20.6 MPLAB ICE High Performance Universal In-Circuit Emulator with MPLAB IDE
The MPLINK object linker combines relocatable objects created by the MPASM assembler and the MPLAB C17 and MPLAB C18 C compilers. It can also link relocatable objects from pre-compiled libraries, using directives from a linker script. The MPLIB object librarian is a librarian for precompiled code to be used with the MPLINK object linker. When a routine from a library is called from another source file, only the modules that contain that routine will be linked in with the application. This allows large libraries to be used efficiently in many different applications. The MPLIB object librarian manages the creation and modification of library files. The MPLINK object linker features include: * Integration with MPASM assembler and MPLAB C17 and MPLAB C18 C compilers. * Allows all memory areas to be defined as sections to provide link-time flexibility. The MPLIB object librarian features include: * Easier linking because single libraries can be included instead of many smaller files. * Helps keep code maintainable by grouping related modules together. * Allows libraries to be created and modules to be added, listed, replaced, deleted or extracted.
The MPLAB ICE universal in-circuit emulator is intended to provide the product development engineer with a complete microcontroller design tool set for PICmicro microcontrollers (MCUs). Software control of the MPLAB ICE in-circuit emulator is provided by the MPLAB Integrated Development Environment (IDE), which allows editing, building, downloading and source debugging from a single environment. The MPLAB ICE 2000 is a full-featured emulator system with enhanced trace, trigger and data monitoring features. Interchangeable processor modules allow the system to be easily reconfigured for emulation of different processors. The universal architecture of the MPLAB ICE in-circuit emulator allows expansion to support new PICmicro microcontrollers. The MPLAB ICE in-circuit emulator system has been designed as a real-time emulation system, with advanced features that are generally found on more expensive development tools. The PC platform and Microsoft(R) Windows environment were chosen to best make these features available to you, the end user.
20.7
ICEPIC In-Circuit Emulator
20.5
MPLAB SIM Software Simulator
The MPLAB SIM software simulator allows code development in a PC-hosted environment by simulating the PICmicro series microcontrollers on an instruction level. On any given instruction, the data areas can be examined or modified and stimuli can be applied from a file, or user-defined key press, to any of the pins. The execution can be performed in single step, execute until break, or trace mode. The MPLAB SIM simulator fully supports symbolic debugging using the MPLAB C17 and the MPLAB C18 C compilers and the MPASM assembler. The software simulator offers the flexibility to develop and debug code outside of the laboratory environment, making it an excellent multiproject software development tool.
The ICEPIC low cost, in-circuit emulator is a solution for the Microchip Technology PIC16C5X, PIC16C6X, PIC16C7X and PIC16CXXX families of 8-bit OneTime-Programmable (OTP) microcontrollers. The modular system can support different subsets of PIC16C5X or PIC16CXXX products through the use of interchangeable personality modules, or daughter boards. The emulator is capable of emulating without target application circuitry being present.
DS39026C-page 230
2001 Microchip Technology Inc.
PIC18CXX2
20.8 MPLAB ICD In-Circuit Debugger
Microchip's In-Circuit Debugger, MPLAB ICD, is a powerful, low cost, run-time development tool. This tool is based on the FLASH PIC16F87X and can be used to develop for this and other PICmicro microcontrollers from the PIC16CXXX family. The MPLAB ICD utilizes the in-circuit debugging capability built into the PIC16F87X. This feature, along with Microchip's In-Circuit Serial ProgrammingTM protocol, offers costeffective in-circuit FLASH debugging from the graphical user interface of the MPLAB Integrated Development Environment. This enables a designer to develop and debug source code by watching variables, singlestepping and setting break points. Running at full speed enables testing hardware in real-time.
20.11 PICDEM 1 Low Cost PICmicro Demonstration Board
The PICDEM 1 demonstration board is a simple board which demonstrates the capabilities of several of Microchip's microcontrollers. The microcontrollers supported are: PIC16C5X (PIC16C54 to PIC16C58A), PIC16C61, PIC16C62X, PIC16C71, PIC16C8X, PIC17C42, PIC17C43 and PIC17C44. All necessary hardware and software is included to run basic demo programs. The user can program the sample microcontrollers provided with the PICDEM 1 demonstration board on a PRO MATE II device programmer, or a PICSTART Plus development programmer, and easily test firmware. The user can also connect the PICDEM 1 demonstration board to the MPLAB ICE incircuit emulator and download the firmware to the emulator for testing. A prototype area is available for the user to build some additional hardware and connect it to the microcontroller socket(s). Some of the features include an RS-232 interface, a potentiometer for simulated analog input, push button switches and eight LEDs connected to PORTB.
20.9
PRO MATE II Universal Device Programmer
The PRO MATE II universal device programmer is a full-featured programmer, capable of operating in stand-alone mode, as well as PC-hosted mode. The PRO MATE II device programmer is CE compliant. The PRO MATE II device programmer has programmable VDD and VPP supplies, which allow it to verify programmed memory at VDD min and VDD max for maximum reliability. It has an LCD display for instructions and error messages, keys to enter commands and a modular detachable socket assembly to support various package types. In stand-alone mode, the PRO MATE II device programmer can read, verify, or program PICmicro devices. It can also set code protection in this mode.
20.12 PICDEM 2 Low Cost PIC16CXX Demonstration Board
The PICDEM 2 demonstration board is a simple demonstration board that supports the PIC16C62, PIC16C64, PIC16C65, PIC16C73 and PIC16C74 microcontrollers. All the necessary hardware and software is included to run the basic demonstration programs. The user can program the sample microcontrollers provided with the PICDEM 2 demonstration board on a PRO MATE II device programmer, or a PICSTART Plus development programmer, and easily test firmware. The MPLAB ICE in-circuit emulator may also be used with the PICDEM 2 demonstration board to test firmware. A prototype area has been provided to the user for adding additional hardware and connecting it to the microcontroller socket(s). Some of the features include a RS-232 interface, push button switches, a potentiometer for simulated analog input, a serial EEPROM to demonstrate usage of the I2CTM bus and separate headers for connection to an LCD module and a keypad.
20.10 PICSTART Plus Entry Level Development Programmer
The PICSTART Plus development programmer is an easy-to-use, low cost, prototype programmer. It connects to the PC via a COM (RS-232) port. MPLAB Integrated Development Environment software makes using the programmer simple and efficient. The PICSTART Plus development programmer supports all PICmicro devices with up to 40 pins. Larger pin count devices, such as the PIC16C92X and PIC17C76X, may be supported with an adapter socket. The PICSTART Plus development programmer is CE compliant.
2001 Microchip Technology Inc.
DS39026C-page 231
PIC18CXX2
20.13 PICDEM 3 Low Cost PIC16CXXX Demonstration Board
The PICDEM 3 demonstration board is a simple demonstration board that supports the PIC16C923 and PIC16C924 in the PLCC package. It will also support future 44-pin PLCC microcontrollers with an LCD Module. All the necessary hardware and software is included to run the basic demonstration programs. The user can program the sample microcontrollers provided with the PICDEM 3 demonstration board on a PRO MATE II device programmer, or a PICSTART Plus development programmer with an adapter socket, and easily test firmware. The MPLAB ICE in-circuit emulator may also be used with the PICDEM 3 demonstration board to test firmware. A prototype area has been provided to the user for adding hardware and connecting it to the microcontroller socket(s). Some of the features include a RS-232 interface, push button switches, a potentiometer for simulated analog input, a thermistor and separate headers for connection to an external LCD module and a keypad. Also provided on the PICDEM 3 demonstration board is a LCD panel, with 4 commons and 12 segments, that is capable of displaying time, temperature and day of the week. The PICDEM 3 demonstration board provides an additional RS-232 interface and Windows software for showing the demultiplexed LCD signals on a PC. A simple serial interface allows the user to construct a hardware demultiplexer for the LCD signals.
20.14 PICDEM 17 Demonstration Board
The PICDEM 17 demonstration board is an evaluation board that demonstrates the capabilities of several Microchip microcontrollers, including PIC17C752, PIC17C756A, PIC17C762 and PIC17C766. All necessary hardware is included to run basic demo programs, which are supplied on a 3.5-inch disk. A programmed sample is included and the user may erase it and program it with the other sample programs using the PRO MATE II device programmer, or the PICSTART Plus development programmer, and easily debug and test the sample code. In addition, the PICDEM 17 demonstration board supports downloading of programs to and executing out of external FLASH memory on board. The PICDEM 17 demonstration board is also usable with the MPLAB ICE in-circuit emulator, or the PICMASTER emulator and all of the sample programs can be run and modified using either emulator. Additionally, a generous prototype area is available for user hardware.
20.15 KEELOQ Evaluation and Programming Tools
KEELOQ evaluation and programming tools support Microchip's HCS Secure Data Products. The HCS evaluation kit includes a LCD display to show changing codes, a decoder to decode transmissions and a programming interface to program test transmitters.
DS39026C-page 232
2001 Microchip Technology Inc.
24CXX/ 25CXX/ 93CXX
PIC14000
HCSXXX
PIC16C5X
PIC16C6X
PIC16C7X
PIC16C8X
PIC17C4X
PIC16F62X
PIC16C7XX
PIC16F8XX
PIC16C9XX
PIC17C7XX
PIC12CXXX
PIC16CXXX
PIC18CXX2
MCRFXXX
MCP2510
TABLE 20-1:
MPLAB(R) Integrated Development Environment
a
a
a
a
a
a
a
a
a
a
a
a
aa
aa
MPLAB(R) C17 C Compiler
Software Tools
MPLAB(R) C18 C Compiler
MPASMTM Assembler/ MPLINKTM Object Linker
a
a
Programmers Debugger Emulators
Demo Boards and Eval Kits
2001 Microchip Technology Inc.
aaa
aa
**
aa
aa
aa
aa
aa
aa
aa
aa
aa
aa
aa
aa
MPLAB(R) ICE In-Circuit Emulator
ICEPICTM In-Circuit Emulator
a
* *
a
a
a
a
a
a
a
MPLAB(R) ICD In-Circuit Debugger
a
**
a
a
PICSTART(R) Plus Entry Level Development Programmer
a
**
a
a
a
a
a
a
a
a
a
a
a
a
a
PRO MATE(R) II Universal Device Programmer
a
a
a
a
a
a
a
a
a
a
a
a
a
a
a
a
PICDEMTM 1 Demonstration Board
a

a
a
a
a
DEVELOPMENT TOOLS FROM MICROCHIP
PICDEMTM 2 Demonstration Board
a
a
a
PICDEMTM 3 Demonstration Board
a
PICDEMTM 14A Demonstration Board
a
PICDEMTM 17 Demonstration Board
a
KEELOQ(R) Evaluation Kit
aa
KEELOQ(R) Transponder Kit
microIDTM Programmer's Kit
aa
125 kHz microIDTM Developer's Kit
125 kHz Anticollision microIDTM Developer's Kit
a
13.56 MHz Anticollision microIDTM Developer's Kit
a
PIC18CXX2
DS39026C-page 233
MCP2510 CAN Developer's Kit
* Contact the Microchip Technology Inc. web site at www.microchip.com for information on how to use the MPLAB(R) ICD In-Circuit Debugger (DV164001) with PIC16C62, 63, 64, 65, 72, 73, 74, 76, 77. ** Contact Microchip Technology Inc. for availability date. Development tool is available on select devices.
a
PIC18CXX2
NOTES:
DS39026C-page 234
2001 Microchip Technology Inc.
PIC18CXX2
21.0 ELECTRICAL CHARACTERISTICS
Absolute Maximum Ratings () Ambient temperature under bias.............................................................................................................-55C to +125C Storage temperature .............................................................................................................................. -65C to +150C Voltage on any pin with respect to VSS (except VDD, MCLR, and RA4) ....................................... -0.3 V to (VDD + 0.3 V) Voltage on VDD with respect to VSS ....................................................................................................... -0.3 V to +7.5 V Voltage on MCLR with respect to VSS (Note 2) ....................................................................................... 0 V to +13.25 V Voltage on RA4 with respect to Vss ............................................................................................................. 0 V to +8.5 V Total power dissipation (Note 1) ..............................................................................................................................1.0 W Maximum current out of VSS pin ...........................................................................................................................300 mA Maximum current into VDD pin ..............................................................................................................................250 mA Input clamp current, IIK (VI < 0 or VI > VDD)...................................................................................................................... 20 mA Output clamp current, IOK (VO < 0 or VO > VDD) .............................................................................................................. 20 mA Maximum output current sunk by any I/O pin..........................................................................................................25 mA Maximum output current sourced by any I/O pin ....................................................................................................25 mA Maximum current sunk by PORTA, PORTB, and PORTE (Note 3) (combined) ...................................................200 mA Maximum current sourced by PORTA, PORTB, and PORTE (Note 3) (combined)..............................................200 mA Maximum current sunk by PORTC and PORTD (Note 3) (combined)..................................................................200 mA Maximum current sourced by PORTC and PORTD (Note 3) (combined).............................................................200 mA Note 1: Power dissipation is calculated as follows: Pdis = VDD x {IDD - IOH} + {(VDD-VOH) x IOH} + (VOl x IOL) 2: Voltage spikes below VSS at the MCLR/VPP pin, inducing currents greater than 80 mA, may cause latch-up. Thus, a series resistor of 50-100 should be used when applying a "low" level to the MCLR/VPP pin, rather than pulling this pin directly to VSS. 3: PORTD and PORTE not available on the PIC18C2X2 devices.
NOTICE: Stresses above those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. This is a stress rating only and functional operation of the device at those or any other conditions above those indicated in the operation listings of this specification is not implied. Exposure to maximum rating conditions for extended periods may affect device reliability.
2001 Microchip Technology Inc.
DS39026C-page 235
PIC18CXX2
FIGURE 21-1: 6.0 V 5.5 V 5.0 V PIC18CXXX 4.2V PIC18CXX2 VOLTAGE-FREQUENCY GRAPH (INDUSTRIAL, EXTENDED)
Voltage
4.5 V 4.0 V 3.5 V 3.0 V 2.5 V 2.0 V
40 MHz
Frequency
FIGURE 21-2:
PIC18LCXX2 VOLTAGE-FREQUENCY GRAPH (INDUSTRIAL) 6.0 V 5.5 V 5.0 V PIC18LCXXX 4.2V
Voltage
4.5 V 4.0 V 3.5 V 3.0 V 2.5 V 2.0 V
6 MHz
40 MHz
Frequency
FMAX = (20.0 MHz/V) (VDDAPPMIN - 2.5 V) + 6 MHz Note: VDDAPPMIN is the minimum voltage of the PICmicro(R) device in the application.
DS39026C-page 236
2001 Microchip Technology Inc.
PIC18CXX2
21.1 DC Characteristics
Standard Operating Conditions (unless otherwise stated) Operating temperature -40C TA +85C for industrial Standard Operating Conditions (unless otherwise stated) Operating temperature -40C TA +85C for industrial -40C TA +125C for extended Min Typ Max Units Conditions PIC18LCXX2 (Industrial) PIC18CXX2 (Industrial, Extended) Param No. D001 D001 D002 D003 Symbol VDD Characteristic
D004
D005
D005
Legend: Note 1: 2:
3:
4:
Supply Voltage PIC18LCXX2 2.5 -- 5.5 V HS, XT, RC and LP osc mode PIC18CXX2 4.2 -- 5.5 V VDR RAM Data Retention 1.5 -- -- V Voltage(1) VDD Start Voltage -- -- 0.7 V See section on Power-on Reset for details VPOR to ensure internal Power-on Reset signal VDD Rise Rate SVDD 0.05 -- -- V/ms See section on Power-on Reset for details to ensure internal Power-on Reset signal Brown-out Reset Voltage VBOR PIC18LCXX2 BORV1:BORV0 = 11 2.5 -- 2.66 V BORV1:BORV0 = 10 2.7 -- 2.86 V BORV1:BORV0 = 01 4.2 -- 4.46 V BORV1:BORV0 = 00 4.5 -- 4.78 V PIC18CXX2 BORV1:BORV0 = 1x N.A. -- N.A. V Not in operating voltage range of device BORV1:BORV0 = 01 4.2 -- 4.46 V BORV1:BORV0 = 00 4.5 -- 4.78 V Shading of rows is to assist in readability of the table. This is the limit to which VDD can be lowered in SLEEP mode, or during a device RESET, without losing RAM data. The supply current is mainly a function of the operating voltage and frequency. Other factors, such as I/O pin loading and switching rate, oscillator type, internal code execution pattern and temperature, also have an impact on the current consumption. The test conditions for all IDD measurements in active operation mode are: OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD MCLR = VDD; WDT enabled/disabled as specified. The power-down current in SLEEP mode does not depend on the oscillator type. Power-down current is measured with the part in SLEEP mode, with all I/O pins in hi-impedance state and tied to VDD or VSS, and all features that add delta current disabled (such as WDT, Timer1 Oscillator, BOR,...). For RC osc configuration, current through REXT is not included. The current through the resistor can be estimated by the formula Ir = VDD/2REXT (mA) with REXT in kOhm.
2001 Microchip Technology Inc.
DS39026C-page 237
PIC18CXX2
21.1 DC Characteristics (Continued)
Standard Operating Conditions (unless otherwise stated) Operating temperature -40C TA +85C for industrial Standard Operating Conditions (unless otherwise stated) Operating temperature -40C TA +85C for industrial -40C TA +125C for extended Min Typ Max Units Conditions PIC18LCXX2 (Industrial) PIC18CXX2 (Industrial, Extended) Param No. Symbol IDD D010 D010 D010A D010A D010C D010C D013 Characteristic Supply Current(2,4) PIC18LCXX2 PIC18CXX2 PIC18LCXX2 PIC18CXX2 PIC18LCXX2 PIC18CXX2 PIC18LCXX2 -- -- -- D013 PIC18CXX2 -- -- D014 D014 PIC18LCXX2 -- PIC18CXX2 -- 55 A -- -- 25 38 mA mA -- -- -- 3.5 25 38 mA mA mA -- -- -- -- -- -- -- -- -- -- -- -- 2 4 55 250 38 38 mA mA A A mA mA XT, RC, RCIO osc configurations FOSC = 4 MHz, VDD = 2.5V XT, RC, RCIO osc configurations FOSC = 4 MHz, VDD = 4.2V LP osc configuration FOSC = 32 kHz, VDD = 2.5V LP osc configuration FOSC = 32 kHz, VDD = 4.2V EC, ECIO osc configurations FOSC = 40 MHz, VDD = 5.5V EC, ECIO osc configurations FOSC = 40 MHz, VDD = 5.5V HS osc configuration FOSC = 6 MHz, VDD = 2.5V FOSC = 25 MHz, VDD = 5.5V HS + PLL osc configurations FOSC = 10 MHz, VDD = 5.5V HS osc configuration FOSC = 25 MHz, VDD = 5.5V HS + PLL osc configurations FOSC = 10 MHz, VDD = 5.5V Timer1 osc configuration FOSC = 32 kHz, VDD = 2.5V
Legend: Note 1: 2:
3:
4:
OSCB osc configuration -- -- 200 A FOSC = 32 kHz, VDD = 4.2V, -40C to +85C -- -- 250 A FOSC = 32 kHz, VDD = 4.2V, -40C to +125C Shading of rows is to assist in readability of the table. This is the limit to which VDD can be lowered in SLEEP mode, or during a device RESET, without losing RAM data. The supply current is mainly a function of the operating voltage and frequency. Other factors, such as I/O pin loading and switching rate, oscillator type, internal code execution pattern and temperature, also have an impact on the current consumption. The test conditions for all IDD measurements in active operation mode are: OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD MCLR = VDD; WDT enabled/disabled as specified. The power-down current in SLEEP mode does not depend on the oscillator type. Power-down current is measured with the part in SLEEP mode, with all I/O pins in hi-impedance state and tied to VDD or VSS, and all features that add delta current disabled (such as WDT, Timer1 Oscillator, BOR,...). For RC osc configuration, current through REXT is not included. The current through the resistor can be estimated by the formula Ir = VDD/2REXT (mA) with REXT in kOhm.
DS39026C-page 238
2001 Microchip Technology Inc.
PIC18CXX2
21.1 DC Characteristics (Continued)
Standard Operating Conditions (unless otherwise stated) Operating temperature -40C TA +85C for industrial Standard Operating Conditions (unless otherwise stated) Operating temperature -40C TA +85C for industrial -40C TA +125C for extended Min Typ Max Units Conditions PIC18LCXX2 (Industrial) PIC18CXX2 (Industrial, Extended) Param No. D020 D020 D021B Symbol IPD Characteristic Power-down Current(3) PIC18LCXX2
D022 D022 D022A D022A D022B D022B D025 D025 Legend: Note 1: 2:
3:
4:
-- <.5 2 A VDD = 2.5V, -40C to +85C -- -- 4 A VDD = 5.5V, -40C to +85C PIC18CXX2 -- <1 3 A VDD = 4.2V, -40C to +85C -- -- 4 A VDD = 5.5V, -40C to +85C -- -- 15 A VDD = 4.2V, -40C to +125C -- -- 20 A VDD = 5.5V, -40C to +125C Module Differential Current Watchdog Timer -- -- 1 A VDD = 2.5V IWDT PIC18LCXX2 -- -- 15 A VDD = 5.5V Watchdog Timer -- -- 15 A VDD = 5.5V, -40C to +85C PIC18CXX2 -- -- 20 A VDD = 5.5V, -40C to +125C IBOR Brown-out Reset -- -- 45 A VDD = 2.5V PIC18LCXX2 Brown-out Reset -- -- 50 A VDD = 5.5V, -40C to +85C PIC18CXX2 -- -- 50 A VDD = 5.5V, -40C to +125 ILVD Low Voltage Detect -- -- 45 A VDD = 2.5V PIC18LCXX2 Low Voltage Detect -- -- 50 A VDD = 4.2V, -40C to +85C PIC18CXX2 -- -- 50 A VDD = 4.2V, -40C to +125C IOSCB Timer1 Oscillator -- -- 15 A VDD = 2.5V PIC18LCXX2 Timer1 Oscillator -- -- 100 A VDD = 4.2V, -40C to +85C PIC18CXX2 -- -- 120 A VDD = 4.2V, -40C to +125C Shading of rows is to assist in readability of the table. This is the limit to which VDD can be lowered in SLEEP mode, or during a device RESET, without losing RAM data. The supply current is mainly a function of the operating voltage and frequency. Other factors, such as I/O pin loading and switching rate, oscillator type, internal code execution pattern and temperature, also have an impact on the current consumption. The test conditions for all IDD measurements in active operation mode are: OSC1 = external square wave, from rail-to-rail; all I/O pins tri-stated, pulled to VDD MCLR = VDD; WDT enabled/disabled as specified. The power-down current in SLEEP mode does not depend on the oscillator type. Power-down current is measured with the part in SLEEP mode, with all I/O pins in hi-impedance state and tied to VDD or VSS, and all features that add delta current disabled (such as WDT, Timer1 Oscillator, BOR,...). For RC osc configuration, current through REXT is not included. The current through the resistor can be estimated by the formula Ir = VDD/2REXT (mA) with REXT in kOhm.
2001 Microchip Technology Inc.
DS39026C-page 239
PIC18CXX2
21.2 DC Characteristics: PIC18CXX2 (Industrial, Extended) PIC18LCXX2 (Industrial)
Standard Operating Conditions (unless otherwise stated) Operating temperature -40C TA +85C for industrial -40C TA +125C for extended Characteristic Input Low Voltage I/O ports: with TTL buffer with Schmitt Trigger buffer RC3 and RC4 MCLR OSC1 (in XT, HS and LP modes) and T1OSI OSC1 (in RC and EC mode)(1) Input High Voltage I/O ports: with TTL buffer Min Max Units Conditions
DC CHARACTERISTICS Param Symbol No. VIL D030 D030A D031 D032 D032A D033 VIH D040 D040A D041 with Schmitt Trigger buffer RC3 and RC4 MCLR, OSC1 (EC mode) OSC1 (in XT, HS and LP modes) and T1OSI OSC1 (RC mode)(1) Input Leakage Current(2,3) I/O ports
Vss -- Vss Vss VSS VSS VSS
0.15VDD 0.8 0.2VDD 0.3VDD 0.2VDD 0.3VDD 0.2VDD
V V V V V V V
VDD < 4.5V 4.5V VDD 5.5V
0.25VDD + 0.8V 2.0 0.8VDD 0.7VDD 0.8VDD 0.7VDD 0.9VDD --
VDD VDD VDD VDD VDD VDD VDD 1
V V V V V V V A
VDD < 4.5V 4.5V VDD 5.5V
D042 D042A D043 IIL D060 D061 D063
-- 5 A MCLR OSC1 -- 5 A IPU Weak Pull-up Current D070 IPURB PORTB weak pull-up current 50 400 A VDD = 5V, VPIN = VSS Note 1: In RC oscillator configuration, the OSC1/CLKIN pin is a Schmitt Trigger input. It is not recommended that the PICmicro MCU be driven with an external clock while in RC mode. 2: The leakage current on the MCLR pin is strongly dependent on the applied voltage level. The specified levels represent normal operating conditions. Higher leakage current may be measured at different input voltages. 3: Negative current is defined as current sourced by the pin.
VSS VPIN VDD, Pin at hi-impedance Vss VPIN VDD Vss VPIN VDD
DS39026C-page 240
2001 Microchip Technology Inc.
PIC18CXX2
21.2 DC Characteristics: PIC18CXX2 (Industrial, Extended) PIC18LCXX2 (Industrial) (Continued)
Standard Operating Conditions (unless otherwise stated) Operating temperature -40C TA +85C for industrial -40C TA +125C for extended Characteristic Output Low Voltage I/O ports Min Max Units Conditions
DC CHARACTERISTICS Param Symbol No. VOL D080 D080A D083 D083A VOH D090 D090A D092 D092A D150 VOD OSC2/CLKOUT (RC mode) Output High Voltage(3) I/O ports OSC2/CLKOUT (RC mode)
-- -- -- --
0.6 0.6 0.6 0.6
V V V V
IOL = 8.5 mA, VDD = 4.5V, -40C to +85C IOL = 7.0 mA, VDD = 4.5V, -40C to +125C IOL = 1.6 mA, VDD = 4.5V, -40C to +85C IOL = 1.2 mA, VDD = 4.5V, -40C to +125C IOH = -3.0 mA, VDD = 4.5V, -40C to +85C IOH = -2.5 mA, VDD = 4.5V, -40C to +125C IOH = -1.3 mA, VDD = 4.5V, -40C to +85C IOH = -1.0 mA, VDD = 4.5V, -40C to +125C RA4 pin
VDD - 0.7 VDD - 0.7 VDD - 0.7 VDD - 0.7
-- -- -- --
V V V V
Open Drain High Voltage -- 8.5 V Capacitive Loading Specs on Output Pins D101 CIO All I/O pins and OSC2 -- 50 pF To meet the AC Timing (in RC mode) Specifications D102 CB SCL, SDA -- 400 pF In I2C mode Note 1: In RC oscillator configuration, the OSC1/CLKIN pin is a Schmitt Trigger input. It is not recommended that the PICmicro MCU be driven with an external clock while in RC mode. 2: The leakage current on the MCLR pin is strongly dependent on the applied voltage level. The specified levels represent normal operating conditions. Higher leakage current may be measured at different input voltages. 3: Negative current is defined as current sourced by the pin.
2001 Microchip Technology Inc.
DS39026C-page 241
PIC18CXX2
FIGURE 21-3: LOW VOLTAGE DETECT CHARACTERISTICS
VDD (LVDIF can be cleared in software)
VLVD (LVDIF set by hardware)
LVDIF
TABLE 21-1:
LOW VOLTAGE DETECT CHARACTERISTICS
Standard Operating Conditions (unless otherwise stated) Operating temperature -40C TA +85C for industrial -40C TA +125C for extended
Param No. D420
Symbol VLVD
Characteristic LVD Voltage LVV<3:0> = 0100 LVV<3:0> = 0101 LVV<3:0> = 0110 LVV<3:0> = 0111 LVV<3:0> = 1000 LVV<3:0> = 1001 LVV<3:0> = 1010 LVV<3:0> = 1011 LVV<3:0> = 1100 LVV<3:0> = 1101 LVV<3:0> = 1110
Min 2.5 2.7 2.8 3.0 3.3 3.5 3.6 3.8 4.0 4.2 4.5
Max 2.66 2.86 2.98 3.2 3.52 3.72 3.84 4.04 4.26 4.46 4.78
Units V V V V V V V V V V V
Conditions
DS39026C-page 242
2001 Microchip Technology Inc.
PIC18CXX2
TABLE 21-2: EPROM PROGRAMMING REQUIREMENTS
Standard Operating Conditions (unless otherwise stated) Operating temperature -40C TA +40C Characteristic Min Max Units Conditions DC CHARACTERISTICS Param. No. Sym
D110 D111 D112 D113 D114 D115
Internal Program Memory Programming Specs (Note 1) VPP Voltage on MCLR/VPP pin VDDP Supply voltage during programming Current into MCLR/VPP pin IPP IDDP Supply current during programming TPROG Programming pulse width TERASE EPROM erase time Device operation 3V Device operation 3V
12.75 4.75 -- -- 50
13.25 5.25 50 30 1000
V V mA mA
(Note 2)
s Terminated via internal/external interrupt or a RESET min. min.
60 30
-- --
Note 1: These specifications are for the programming of the on-chip program memory EPROM through the use of the table write instructions. The complete programming specifications can be found in the PIC18CXXX Programming Specifications (Literature Number DS39028). 2: The MCLR/VPP pin may be kept in this range at times other than programming, but is not recommended.
2001 Microchip Technology Inc.
DS39026C-page 243
PIC18CXX2
21.3
21.3.1
AC (Timing) Characteristics
TIMING PARAMETER SYMBOLOGY
The timing parameter symbols have been created following one of the following formats: 1. TppS2ppS 2. TppS T F Frequency Lowercase letters (pp) and their meanings: pp cc CCP1 ck CLKOUT cs CS di SDI do SDO dt Data in io I/O port mc MCLR Uppercase letters and their meanings: S F Fall H High I Invalid (Hi-impedance) L Low I2C only AA output access BUF Bus free TCC:ST (I2C specifications only) CC HD Hold ST DAT DATA input hold STA START condition 3. TCC:ST 4. Ts T (I2C specifications only) (I2C specifications only) Time
osc rd rw sc ss t0 t1 wr
OSC1 RD RD or WR SCK SS T0CKI T1CKI WR
P R V Z High Low
Period Rise Valid Hi-impedance High Low
SU STO
Setup STOP condition
DS39026C-page 244
2001 Microchip Technology Inc.
PIC18CXX2
21.3.2 TIMING CONDITIONS
The temperature and voltages specified in Table 21-3 apply to all timing specifications unless otherwise noted. Figure 21-4 specifies the load conditions for the timing specifications.
TABLE 21-3:
TEMPERATURE AND VOLTAGE SPECIFICATIONS - AC
Standard Operating Conditions (unless otherwise stated) Operating temperature -40C TA +85C for industrial -40C TA +125C for extended Operating voltage VDD range as described in DC spec Section 21.1. LC parts operate for industrial temperatures only.
AC CHARACTERISTICS
FIGURE 21-4:
LOAD CONDITIONS FOR DEVICE TIMING SPECIFICATIONS
Load condition 1 VDD/2 CL VSS Pin VSS CL RL = 464 CL = 50 pF for all pins except OSC2/CLKOUT and including D and E outputs as ports Load condition 2
RL
Pin
2001 Microchip Technology Inc.
DS39026C-page 245
PIC18CXX2
21.3.3 TIMING DIAGRAMS AND SPECIFICATIONS EXTERNAL CLOCK TIMING (ALL MODES EXCEPT PLL)
Q4 Q1 Q2 Q3 Q4 Q1
FIGURE 21-5:
OSC1
1 2 3 3 4 4
CLKOUT
TABLE 21-4:
EXTERNAL CLOCK TIMING REQUIREMENTS
Characteristic External CLKIN Frequency(1) Min DC DC 4 DC DC DC 0.1 4 4 5 250 40 100 25 25 250 250 25 100 25 Max 4 25 10 40 40 4 4 25 10 200 -- -- 250 -- -- -- 10,000 250 250 -- Units MHz MHz MHz kHz MHz MHz MHz MHz MHz kHz ns ns ns s ns ns ns ns ns s Conditions XT osc HS osc HS + PLL osc LP osc EC, ECIO RC osc XT osc HS osc HS + PLL osc LP osc mode XT and RC osc HS osc HS + PLL osc LP osc EC, ECIO RC osc XT osc HS osc HS + PLL osc LP osc
Param. No. Symbol 1A FOSC
Oscillator Frequency(1)
1
TOSC
External CLKIN Period(1)
Oscillator Period(1)
2 3
100 -- ns TCY = 4/FOSC 30 -- ns XT osc 2.5 -- s LP osc 10 -- ns HS osc 4 TosR, External Clock in (OSC1) -- 20 ns XT osc TosF Rise or Fall Time -- 50 ns LP osc -- 7.5 ns HS osc Note 1: Instruction cycle period (TCY) equals four times the input oscillator time-base period for all configurations except PLL. All specified values are based on characterization data for that particular oscillator type under standard operating conditions with the device executing code. Exceeding these specified limits may result in an unstable oscillator operation and/or higher than expected current consumption. All devices are tested to operate at "min." values with an external clock applied to the OSC1/CLKIN pin. When an external clock input is used, the "max." cycle time limit is "DC" (no clock) for all devices.
TCY TosL, TosH
Instruction Cycle Time(1) External Clock in (OSC1) High or Low Time
DS39026C-page 246
2001 Microchip Technology Inc.
PIC18CXX2
TABLE 21-5:
Param Symbol No. TRC CLK
PLL CLOCK TIMING SPECIFICATION (VDD = 4.2V - 5.5V)
Characteristic PLL Start-up Time (Lock Time) CLKOUT Stability (Jitter) using PLL Min -- -2 Max 2 +2 Units ms % Conditions
FIGURE 21-6:
CLKOUT AND I/O TIMING
Q4 Q1 Q2 Q3
OSC1 10 CLKOUT 13 14 I/O Pin (input) 17 I/O Pin (output) old value 20, 21 Note: Refer to Figure 21-4 for load conditions. 15 new value 19 18 12 16 11
TABLE 21-6:
Param. No. 10 11 12 13 14 15 16 17 18 18A
CLKOUT AND I/O TIMING REQUIREMENTS
Characteristic Min Typ Max Units Conditions ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns (1) (1) (1) (1) (1) (1) (1)
Symbol TosH2ckL TosH2ckH TckR TckF TckL2ioV TioV2ckH TckH2ioI TosH2ioV TosH2ioI
OSC1 to CLKOUT -- 75 200 OSC1 to CLKOUT -- 75 200 CLKOUT rise time -- 35 100 CLKOUT fall time -- 35 100 CLKOUT to Port out valid -- -- 0.5TCY + 20 Port in valid before CLKOUT 0.25TCY + 25 -- -- Port in hold after CLKOUT 0 -- -- OSC1 (Q1 cycle) to Port out valid -- 50 150 OSC1 (Q2 cycle) to PIC18CXXX 100 -- -- Port input invalid PIC18LCXXX 200 -- -- (I/O in hold time) 19 TioV2osH Port input valid to OSC1 0 -- -- (I/O in setup time) 20 TioR Port output rise time PIC18CXXX -- 12 25 20A PIC18LCXXX -- -- 50 21 TioF Port output fall time PIC18CXXX -- 12 25 21A PIC18LCXXX -- -- 50 22 TINP INT pin high or low time TCY -- -- 23 TRBP RB7:RB4 change INT high or low time TCY -- -- 24 TRCP RC7:RC4 change INT high or low time 20 These parameters are asynchronous events not related to any internal clock edges. Note 1: Measurements are taken in RC mode where CLKOUT output is 4 x TOSC.
2001 Microchip Technology Inc.
DS39026C-page 247
PIC18CXX2
FIGURE 21-7: RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND POWER-UP TIMER TIMING
VDD MCLR Internal POR 33 PWRT Time-out OSC Time-out Internal Reset Watchdog Timer Reset 34 I/O Pins Note: Refer to Figure 21-4 for load conditions. 32 30
31
34
FIGURE 21-8:
BROWN-OUT RESET TIMING
BVDD
VDD
35 VBGAP = 1.2V
VIRVST
Enable Internal Reference Voltage Internal Reference Voltage Stable 36
TABLE 21-7:
RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER, POWER-UP TIMER AND BROWN-OUT RESET REQUIREMENTS
Characteristic Min Typ -- 18 -- 72 2 -- 20 Max -- 33 1024TOSC 132 -- -- 50 Units s ms -- ms s s s TOSC = OSC1 period Conditions
Param. Symbol No. 30 31 32 33 34 35 36 TmcL TWDT TOST TPWRT TIOZ TBOR Tivrst
2 MCLR Pulse Width (low) Watchdog Timer Time-out Period 7 (No Postscaler) Oscillation Start-up Timer Period 1024TOSC Power up Timer Period 28 I/O Hi-impedance from MCLR -- Low or Watchdog Timer Reset Brown-out Reset Pulse Width 200 Time for Internal Reference -- Voltage to become stable
VDD BVDD (See D005)
DS39026C-page 248
2001 Microchip Technology Inc.
PIC18CXX2
FIGURE 21-9:
T0CKI
TIMER0 AND TIMER1 EXTERNAL CLOCK TIMINGS
40
41
42 T1OSO/T1CKI
45
46
47 TMR0 or TMR1 Note: Refer to Figure 21-4 for load conditions.
48
TABLE 21-8:
Param No. 40 41 42
TIMER0 AND TIMER1 EXTERNAL CLOCK REQUIREMENTS
Characteristic T0CKI High Pulse Width T0CKI Low Pulse Width T0CKI Period No Prescaler With Prescaler No Prescaler With Prescaler No Prescaler With Prescaler Min 0.5TCY + 20 10 0.5TCY + 20 10 TCY + 10 Greater of: 20 nS or TCY + 40 N 0.5TCY + 20 10 25 30 40 0.5TCY + 20 15 30 30 40 Greater of: 20 nS or TCY + 40 N 60 DC 2TOSC Max -- -- -- -- -- -- Units ns ns ns ns ns ns Conditions
Symbol Tt0H Tt0L Tt0P
N = prescale value (1, 2, 4,..., 256)
45
Tt1H
T1CKI High Time
46
Tt1L
T1CKI Low Time
47
Tt1P
T1CKI input period
Synchronous, no prescaler Synchronous, PIC18CXXX with prescaler PIC18LCXXX Asynchronous PIC18CXXX PIC18LCXXX Synchronous, no prescaler Synchronous, PIC18CXXX with prescaler PIC18LCXXX Asynchronous PIC18CXXX PIC18LCXXX Synchronous
-- -- -- -- -- -- -- -- -- -- --
ns ns ns ns ns ns ns ns ns ns ns
N = prescale value (1, 2, 4, 8)
48
Asynchronous Ft1 T1CKI oscillator input frequency range Tcke2tmrI Delay from external T1CKI clock edge to timer increment
-- 50 7TOSC
ns kHz --
2001 Microchip Technology Inc.
DS39026C-page 249
PIC18CXX2
FIGURE 21-10: CAPTURE/COMPARE/PWM TIMINGS (CCP1 AND CCP2)
CCPx (Capture Mode)
50 52
51
CCPx (Compare or PWM Mode) 53 Note: Refer to Figure 21-4 for load conditions. 54
TABLE 21-9:
CAPTURE/COMPARE/PWM REQUIREMENTS (CCP1 AND CCP2)
Characteristic CCPx input low No Prescaler time With PIC18CXXX Prescaler PIC18LCXXX No Prescaler With PIC18CXXX Prescaler PIC18LCXXX CCPx input period CCPx output fall time CCPx output fall time PIC18CXXX PIC18LCXXX PIC18CXXX PIC18LCXXX CCPx input high time Min 0.5TCY + 20 10 20 0.5TCY + 20 10 20 3TCY + 40 N -- -- -- -- Max -- -- -- -- -- -- -- 25 50 25 50 Units ns ns ns ns ns ns ns ns ns ns ns Conditions
Param. Symbol No. 50 TccL
51
TccH
52 53 54
TccP TccR TccF
N = prescale value (1,4 or 16)
DS39026C-page 250
2001 Microchip Technology Inc.
PIC18CXX2
FIGURE 21-11:
RE2/CS
PARALLEL SLAVE PORT TIMING (PIC18C4X2)
RE0/RD
RE1/WR
65 RD7:RD0 62 63 Note: Refer to Figure 21-4 for load conditions.
64
TABLE 21-10: PARALLEL SLAVE PORT REQUIREMENTS (PIC18C4X2)
Param. No. 62 63 64 65 66 Symbol Characteristic Min 20 25 20 35 -- -- 10 -- Max -- -- -- -- 80 90 30 3TCY Units ns ns ns ns ns ns ns Conditions
TdtV2wrH Data in valid before WR or CS (setup time) TwrH2dtI WR or CS to data-in invalid PIC18CXXX (hold time) PIC18LCXXX TrdL2dtV RD and CS to data-out valid TrdH2dtI TibfINH RD or CS to data-out invalid Inhibit of the IBF flag bit being cleared from WR or CS
Extended Temp. Range
Extended Temp. Range
2001 Microchip Technology Inc.
DS39026C-page 251
PIC18CXX2
FIGURE 21-12:
SS 70 SCK (CKP = 0) 71 72 78 SCK (CKP = 1) 79 78 79
EXAMPLE SPI MASTER MODE TIMING (CKE = 0)
80 SDO MSb 75, 76 SDI MSb IN 74 73 Note: Refer to Figure 21-4 for load conditions. BIT6 - - - -1
BIT6 - - - - - -1
LSb
LSb IN
TABLE 21-11: EXAMPLE SPI MODE REQUIREMENTS (MASTER MODE, CKE = 0)
Param. No. 70 71 71A 72 72A 73 73A 74 75 76 78 Symbol TssL2scH, TssL2scL TscH TscL TdiV2scH, TdiV2scL TB2B TscH2diL, TscL2diL TdoR TdoF TscR Characteristic SS to SCK or SCK input Continuous Single Byte SCK input low time Continuous (Slave mode) Single Byte Setup time of SDI data input to SCK edge Last clock edge of Byte1 to the 1st clock edge of Byte2 Hold time of SDI data input to SCK edge SDO data output rise time SDO data output fall time SCK output rise time (Master mode) PIC18CXXX PIC18LCXXX SCK input high time (Slave mode) Min TCY 1.25TCY + 30 40 1.25TCY + 30 40 100 1.5TCY + 40 100 -- -- -- -- -- -- -- -- Max Units -- -- -- -- -- -- -- -- 25 45 25 25 45 25 50 100 ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns (Note 2) Conditions
(Note 1) (Note 1)
PIC18CXXX PIC18LCXXX 79 TscF SCK output fall time (Master mode) 80 TscH2doV, SDO data output valid after PIC18CXXX TscL2doV SCK edge PIC18LCXXX Note 1: Requires the use of Parameter # 73A. 2: Only if Parameter # 71A and # 72A are used.
DS39026C-page 252
2001 Microchip Technology Inc.
PIC18CXX2
FIGURE 21-13:
SS 81 SCK (CKP = 0) 71 73 SCK (CKP = 1) 80 78 72 79
EXAMPLE SPI MASTER MODE TIMING (CKE = 1)
SDO
MSb 75, 76
BIT6 - - - - - -1
LSb
SDI
MSb IN 74
BIT6 - - - -1
LSb IN
Note:
Refer to Figure 21-4 for load conditions.
TABLE 21-12: EXAMPLE SPI MODE REQUIREMENTS (MASTER MODE, CKE = 1)
Param. No. 71 71A 72 72A 73 73A 74 75 76 78 Symbol TscH TscL TdiV2scH, TdiV2scL TB2B TscH2diL, TscL2diL TdoR TdoF TscR Characteristic Continuous Single Byte SCK input low time Continuous (Slave mode) Single Byte Setup time of SDI data input to SCK edge Last clock edge of Byte1 to the 1st clock edge of Byte2 Hold time of SDI data input to SCK edge SDO data output rise time SDO data output fall time SCK output rise time (Master mode) PIC18CXXX PIC18LCXXX SCK input high time (Slave mode) Min 1.25TCY + 30 40 1.25TCY + 30 40 100 1.5TCY + 40 100 -- -- -- -- -- Max Units -- -- -- -- -- -- -- 25 45 25 25 45 25 50 100 -- ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns (Note 2) Conditions
(Note 1) (Note 1)
PIC18CXXX PIC18LCXXX 79 TscF SCK output fall time (Master mode) 80 TscH2doV, SDO data output valid after PIC18CXXX TscL2doV SCK edge PIC18LCXXX 81 TdoV2scH, SDO data output setup to SCK edge TdoV2scL Note 1: Requires the use of Parameter # 73A. 2: Only if Parameter # 71A and # 72A are used.
TCY
2001 Microchip Technology Inc.
DS39026C-page 253
PIC18CXX2
FIGURE 21-14:
SS 70 SCK (CKP = 0) 71 72 83
EXAMPLE SPI SLAVE MODE TIMING (CKE = 0)
78
79
SCK (CKP = 1) 79 78
80 SDO MSb 75, 76 SDI 73 Note: Refer to Figure 21-4 for load conditions. MSb IN 74 BIT6 - - - -1
BIT6 - - - - - -1
LSb 77 LSb IN
TABLE 21-13: EXAMPLE SPI MODE REQUIREMENTS (SLAVE MODE TIMING (CKE = 0))
Param. No. 70 71 71A 72 72A 73 Symbol Characteristic Min TCY 1.25TCY + 30 40 1.25TCY + 30 40 100 1.5TCY + 40 100 -- -- 10 -- -- -- 1.5TCY + 40 Max Units Conditions -- -- -- -- -- -- -- -- 25 45 25 50 25 45 25 50 100 -- ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns
Continuous Single Byte TscL SCK input low time Continuous (Slave mode) Single Byte TdiV2scH, Setup time of SDI data input to SCK edge TdiV2scL Last clock edge of Byte1 to the first clock edge of Byte2 73A TB2B 74 TscH2diL, Hold time of SDI data input to SCK edge TscL2diL 75 TdoR SDO data output rise time PIC18CXXX PIC18LCXXX 76 TdoF SDO data output fall time 77 TssH2doZ SS to SDO output hi-impedance 78 TscR SCK output rise time PIC18CXXX (Master mode) PIC18LCXXX 79 TscF SCK output fall time (Master mode) 80 TscH2doV, SDO data output valid after SCK PIC18CXXX TscL2doV edge PIC18LCXXX 83 TscH2ssH, SS after SCK edge TscL2ssH Note 1: Requires the use of Parameter # 73A. 2: Only if Parameter # 71A and # 72A are used.
TssL2scH, SS to SCK or SCK input TssL2scL TscH SCK input high time (Slave mode)
(Note 1) (Note 1)
(Note 2)
DS39026C-page 254
2001 Microchip Technology Inc.
PIC18CXX2
FIGURE 21-15:
SS
EXAMPLE SPI SLAVE MODE TIMING (CKE = 1)
82
SCK (CKP = 0)
70 83 71 72
SCK (CKP = 1) 80
SDO
MSb 75, 76
BIT6 - - - - - -1
LSb 77
SDI
MSb IN 74
BIT6 - - - -1
LSb IN
Note:
Refer to Figure 21-4 for load conditions.
TABLE 21-14: EXAMPLE SPI SLAVE MODE REQUIREMENTS (CKE = 1)
Param. No. 70 71 71A 72 72A 73A 74 75 76 77 78 Symbol TssL2scH, TssL2scL TscH TscL TB2B TscH2diL, TscL2diL TdoR TdoF TssH2doZ TscR Characteristic SS to SCK or SCK input SCK input high time (Slave mode) Min TCY Max Units Conditions -- -- -- -- -- -- -- 25 45 25 50 25 45 25 50 100 50 100 -- ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns ns
Continuous 1.25TCY + 30 Single Byte 40 SCK input low time Continuous 1.25TCY + 30 (Slave mode) Single Byte 40 Last clock edge of Byte1 to the first clock edge of Byte2 1.5TCY + 40 Hold time of SDI data input to SCK edge 100 SDO data output rise time PIC18CXXX PIC18LCXXX -- -- 10 -- -- -- -- -- -- -- 1.5TCY + 40
(Note 1) (Note 1) (Note 2)
SDO data output fall time SS to SDO output hi-impedance SCK output rise time PIC18CXXX (Master mode) PIC18LCXXX 79 TscF SCK output fall time (Master mode) 80 TscH2doV, SDO data output valid after SCK PIC18CXXX TscL2doV edge PIC18LCXXX 82 TssL2doV SDO data output valid after SS PIC18CXXX edge PIC18LCXXX 83 TscH2ssH, SS after SCK edge TscL2ssH Note 1: Requires the use of Parameter # 73A. 2: Only if Parameter # 71A and # 72A are used.
2001 Microchip Technology Inc.
DS39026C-page 255
PIC18CXX2
FIGURE 21-16: I2C BUS START/STOP BITS TIMING
SCL 90 SDA
91 92
93
START Condition Note: Refer to Figure 21-4 for load conditions.
STOP Condition
TABLE 21-15: I2C BUS START/STOP BITS REQUIREMENTS (SLAVE MODE)
Param. Symbol No. 90 91 92 93 Tsu:sta Thd:sta Tsu:sto Thd:sto Characteristic START condition Setup time START condition Hold time STOP condition Setup time STOP condition Hold time 100 kHz mode 400 kHz mode 100 kHz mode 400 kHz mode 100 kHz mode 400 kHz mode 100 kHz mode 400 kHz mode Min 4700 600 4000 600 4700 600 4000 600 Max -- -- -- -- -- -- -- -- Units ns ns ns ns Conditions Only relevant for Repeated START condition After this period the first clock pulse is generated
DS39026C-page 256
2001 Microchip Technology Inc.
PIC18CXX2
FIGURE 21-17: I2C BUS DATA TIMING
103 100 101 102
SCL
90 91 106 107 92
SDA In
110 109 109
SDA Out Note: Refer to Figure 21-4 for load conditions.
TABLE 21-16: I2C BUS DATA REQUIREMENTS (SLAVE MODE)
Param. No. 100 Symbol THIGH Characteristic Clock high time 100 kHz mode 400 kHz mode SSP Module 101 TLOW Clock low time 100 kHz mode 400 kHz mode SSP Module 102 TR SDA and SCL rise time SDA and SCL fall time 100 kHz mode 400 kHz mode 100 kHz mode 400 kHz mode 90 91 106 107 92 109 110 D102 TSU:STA THD:STA THD:DAT TSU:DAT TSU:STO TAA TBUF CB START condition setup time START condition hold time Data input hold time Data input setup time STOP condition setup time Output valid from clock Bus free time Bus capacitive loading 100 kHz mode 400 kHz mode 100 kHz mode 400 kHz mode 100 kHz mode 400 kHz mode 100 kHz mode 400 kHz mode 100 kHz mode 400 kHz mode 100 kHz mode 400 kHz mode 100 kHz mode 400 kHz mode Min 4.0 0.6 1.5TCY 4.7 1.3 1.5TCY -- 20 + 0.1CB -- 20 + 0.1CB 4.7 0.6 4.0 0.6 0 0 250 100 4.7 0.6 -- -- 4.7 1.3 -- Max -- -- -- -- -- -- 1000 300 300 300 -- -- -- -- -- 0.9 -- -- -- -- 3500 -- -- -- 400 ns ns ns ns s s s s ns s ns ns s s ns ns s s pF Time the bus must be free before a new transmission can start (Note 1) (Note 2) CB is specified to be from 10 to 400 pF Only relevant for Repeated START condition After this period the first clock pulse is generated CB is specified to be from 10 to 400 pF s s PIC18CXXX must operate at a minimum of 1.5 MHz PIC18CXXX must operate at a minimum of 10 MHz Units s s Conditions PIC18CXXX must operate at a minimum of 1.5 MHz PIC18CXXX must operate at a minimum of 10 MHz
103
TF
Note 1: As a transmitter, the device must provide this internal minimum delay time to bridge the undefined region (min. 300 ns) of the falling edge of SCL to avoid unintended generation of START or STOP conditions. 2: A fast mode I2C bus device can be used in a standard mode I2C bus system, but the requirement TSU:DAT 250 ns must then be met. This will automatically be the case if the device does not stretch the LOW period of the SCL signal. If such a device does stretch the LOW period of the SCL signal, it must output the next data bit to the SDA line. TR max. + TSU:DAT = 1000 + 250 = 1250 ns (according to the standard mode I2C bus specification) before the SCL line is released.
2001 Microchip Technology Inc.
DS39026C-page 257
PIC18CXX2
FIGURE 21-18: MASTER SSP I2C BUS START/STOP BITS TIMING WAVEFORMS
SCL 90 SDA
91 92
93
START Condition Note: Refer to Figure 21-4 for load conditions.
STOP Condition
TABLE 21-17: MASTER SSP I2C BUS START/STOP BITS REQUIREMENTS
Param. Symbol No. 90 TSU:STA Characteristic START condition Setup time 91 THD:STA START condition Hold time 92 TSU:STO STOP condition Setup time 93 THD:STO STOP condition Hold time 100 kHz mode 400 kHz mode 1 MHz mode(1) 100 kHz mode 400 kHz mode 1 MHz mode
(1)
Min 2(TOSC)(BRG + 1) 2(TOSC)(BRG + 1) 2(TOSC)(BRG + 1) 2(TOSC)(BRG + 1) 2(TOSC)(BRG + 1) 2(TOSC)(BRG + 1) 2(TOSC)(BRG + 1) 2(TOSC)(BRG + 1) 2(TOSC)(BRG + 1) 2(TOSC)(BRG + 1) 2(TOSC)(BRG + 1) 2(TOSC)(BRG + 1)
Max -- -- -- -- -- -- -- -- -- -- -- --
Units ns
Conditions Only relevant for Repeated START condition After this period the first clock pulse is generated
ns
100 kHz mode 400 kHz mode 1 MHz mode
(1)
ns
100 kHz mode 400 kHz mode 1 MHz mode(1)
2
ns
Note 1: Maximum pin capacitance = 10 pF for all I C pins.
DS39026C-page 258
2001 Microchip Technology Inc.
PIC18CXX2
FIGURE 21-19: MASTER SSP I2C BUS DATA TIMING
103 100 101 102
SCL SDA In
90
91
106
107
92
109
109
110
SDA Out Note: Refer to Figure 21-4 for load conditions.
TABLE 21-18: MASTER SSP I2C BUS DATA REQUIREMENTS
Param. Symbol No. 100 THIGH Characteristic Clock high time Min Max Units Conditions
100 kHz mode 2(TOSC)(BRG + 1) -- ms -- ms 400 kHz mode 2(TOSC)(BRG + 1) 1 MHz mode(1) 2(TOSC)(BRG + 1) -- ms Clock low time 100 kHz mode 2(TOSC)(BRG + 1) -- ms 101 TLOW 400 kHz mode 2(TOSC)(BRG + 1) -- ms (1) 1 MHz mode 2(TOSC)(BRG + 1) -- ms 102 TR SDA and SCL 100 kHz mode -- 1000 ns CB is specified to be 300 ns rise time 400 kHz mode 20 + 0.1CB from 10 to 400 pF -- 300 ns 1 MHz mode(1) SDA and SCL 100 kHz mode -- 300 ns CB is specified to be 103 TF 300 ns fall time 400 kHz mode 20 + 0.1CB from 10 to 400 pF 1 MHz mode(1) -- 100 ns START condition 100 kHz mode 2(TOSC)(BRG + 1) -- ms Only relevant for 90 TSU:STA setup time 400 kHz mode 2(TOSC)(BRG + 1) Repeated START -- ms condition 1 MHz mode(1) 2(TOSC)(BRG + 1) -- ms 91 THD:STA START condition 100 kHz mode 2(TOSC)(BRG + 1) -- ms After this period the -- ms hold time 400 kHz mode 2(TOSC)(BRG + 1) first clock pulse is (1) generated 2(TOSC)(BRG + 1) -- ms 1 MHz mode 100 kHz mode 0 -- ns 106 THD:DAT Data input hold time 400 kHz mode 0 0.9 ms TBD -- ns 1 MHz mode(1) 100 kHz mode 250 -- ns (Note 2) 107 TSU:DAT Data input setup time 400 kHz mode 100 -- ns 1 MHz mode(1) TBD -- ns 92 TSU:STO STOP condition 100 kHz mode 2(TOSC)(BRG + 1) -- ms -- ms setup time 400 kHz mode 2(TOSC)(BRG + 1) 1 MHz mode(1) 2(TOSC)(BRG + 1) -- ms Output valid from 100 kHz mode -- 3500 ns 109 TAA clock 400 kHz mode -- 1000 ns (1) -- -- ns 1 MHz mode Bus free time 100 kHz mode 4.7 -- ms Time the bus must be 110 TBUF 400 kHz mode 1.3 -- ms free before a new transmission can start 1 MHz mode(1) TBD -- ms D102 CB Bus capacitive loading -- 400 pF Note 1: Maximum pin capacitance = 10 pF for all I2C pins. 2: A fast mode I2C bus device can be used in a standard mode I2C bus system, but parameter #107 250 ns must then be met. This will automatically be the case if the device does not stretch the LOW period of the SCL signal. If such a device does stretch the LOW period of the SCL signal, it must output the next data bit to the SDA line, parameter #102 + parameter #107 = 1000 + 250 = 1250 ns (for 100 kHz mode) before the SCL line is released.
2001 Microchip Technology Inc.
DS39026C-page 259
PIC18CXX2
FIGURE 21-20: USART SYNCHRONOUS TRANSMISSION (MASTER/SLAVE) TIMING
RC6/TX/CK pin RC7/RX/DT pin 120 Note:
121
121
122
Refer to Figure 21-4 for load conditions.
TABLE 21-19: USART SYNCHRONOUS TRANSMISSION REQUIREMENTS
Param. No. 120 Symbol Characteristic Min Max Units Conditions
TckH2dtV SYNC XMIT (MASTER & SLAVE) Clock high to data out valid Tckrf Tdtrf Clock out rise time and fall time (Master mode) Data out rise time and fall time
121 122
PIC18CXXX PIC18LCXXX PIC18CXXX PIC18LCXXX PIC18CXXX PIC18LCXXX
-- -- -- -- -- --
40 100 25 50 25 50
ns ns ns ns ns ns
FIGURE 21-21:
USART SYNCHRONOUS RECEIVE (MASTER/SLAVE) TIMING
RC6/TX/CK pin RC7/RX/DT pin
125
126 Note: Refer to Figure 21-4 for load conditions.
TABLE 21-20: USART SYNCHRONOUS RECEIVE REQUIREMENTS
Param. No. 125 126 Symbol TdtV2ckl TckL2dtl Characteristic SYNC RCV (MASTER & SLAVE) Data hold before CK (DT hold time) Data hold after CK (DT hold time) Min Max Units Conditions
10 15
-- --
ns ns
DS39026C-page 260
2001 Microchip Technology Inc.
PIC18CXX2
TABLE 21-21: A/D CONVERTER CHARACTERISTICS: PIC18CXX2 (INDUSTRIAL, EXTENDED) PIC18LCXX2 (INDUSTRIAL)
Param Symbol No. A01 A03 A04 A05 A06 A10 A20 A20A A21 A22 A25 A30 A40 VREFH VREFL VAIN ZAIN IAD NR EIL EDL EFS EOFF -- VREF Characteristic Resolution Integral linearity error Differential linearity error Full scale error Offset error Monotonicity Reference voltage (VREFH - VREFL) Reference voltage High Reference voltage Low Analog input voltage Recommended impedance of analog voltage source A/D conversion PIC18CXXX current (VDD) PIC18LCXXX VREF input current (Note 2) 0V 3V AVSS AVSS 0.3V AVSS 0.3V -- -- -- 10 Min -- -- -- -- -- -- -- -- -- -- Typ -- -- -- -- -- -- -- -- -- -- guaranteed(3) -- -- -- -- -- -- 180 90 -- -- -- AVDD + 0.3V AVDD VREF + 0.3V 10.0 -- -- 1000 Max 10 10 <1 <2 <1 <2 <1 <1 <1 <1 Units bit bit Conditions VREF = VDD 3.0V VREF = VDD < 3.0V
LSb VREF = VDD 3.0V LSb VREF = VDD < 3.0V LSb VREF = VDD 3.0V LSb VREF = VDD < 3.0V LSb VREF = VDD 3.0V LSb VREF = VDD < 3.0V LSb VREF = VDD 3.0V LSb VREF = VDD < 3.0V -- V V V V V k A A A Average current consumption when A/D is on (Note 1). During VAIN acquisition. Based on differential of VHOLD to VAIN. To charge CHOLD, see Section 16.0. During A/D conversion cycle. For 10-bit resolution VSS VAIN VREF
A50
IREF
--
--
10
A
Note 1: When A/D is off, it will not consume any current other than minor leakage current. The power-down current spec includes any such leakage from the A/D module. VREF current is from RA2/AN2/VREF- and RA3/AN3/VREF+ pins or AVDD and AVSS pins, whichever is selected as reference input. 2: VSS VAIN VREF 3: The A/D conversion result never decreases with an increase in the Input Voltage, and has no missing codes.
2001 Microchip Technology Inc.
DS39026C-page 261
PIC18CXX2
FIGURE 21-22: A/D CONVERSION TIMING
BSF ADCON0, GO Note 2 Q4 130 A/D CLK 132 131
A/D DATA
9
8
7
...
...
2
1
0
ADRES
OLD_DATA
NEW_DATA
ADIF GO SAMPLING STOPPED DONE
TCY
SAMPLE
Note 1: If the A/D clock source is selected as RC, a time of TCY is added before the A/D clock starts. This allows the SLEEP instruction to be executed. 2: This is a minimal RC delay (typically 100 ns), which also disconnects the holding capacitor from the analog input.
TABLE 21-22: A/D CONVERSION REQUIREMENTS
Param Symbol No. 130 TAD Characteristic A/D clock period PIC18CXXX PIC18LCXXX PIC18CXXX PIC18LCXXX 131 132 135 136 TCNV TACQ TSWC TAMP Conversion time (not including acquisition time) (Note 1) Acquisition time (Note 3) Switching Time from convert sample Amplifier settling time (Note 2) Min 1.6 3.0 2.0 3.0 11 15 10 -- 1 Max 20(5) 20(5) 6.0 9.0 12 -- -- (Note 4) -- s This may be used if the "new" input voltage has not changed by more than 1 LSb (i.e., 5 mV @ 5.12V) from the last sampled voltage (as stated on CHOLD). Units s s s s TAD s s -40C Temp 125C 0C Temp 125C Conditions TOSC based, VREF 3.0V TOSC based, VREF full range A/D RC mode A/D RC mode
Note 1: ADRES register may be read on the following TCY cycle. 2: See Section 16.0 for minimum conditions, when input voltage has changed more than 1 LSb. 3: The time for the holding capacitor to acquire the "New" input voltage, when the voltage changes full scale after the conversion (AVDD to AVSS, or AVSS to AVDD). The source impedance (RS) on the input channels is 50 . 4: On the next Q4 cycle of the device clock. 5: The time of the A/D clock period is dependent on the device frequency and the TAD clock divider.
DS39026C-page 262
2001 Microchip Technology Inc.
PIC18CXX2
22.0 DC AND AC CHARACTERISTICS GRAPHS AND TABLES
The graphs and tables provided in this section are for design guidance and are not tested. The data presented in this section is a statistical summary of data collected on units from different lots over a period of time and matrix samples. 'Typical' represents the mean of the distribution at 25C. 'Max' or 'min' represents (mean + 3) or (mean - 3) respectively, where is standard deviation, over the whole temperature range.
FIGURE 22-1:
16
TYPICAL IDD vs. FOSC OVER VDD (HS MODE)
14
Typical: statistical mean @ 25C Maximum: mean + 3s (-40C to 125C) Minimum: mean - 3 (-40C to 125C)
5.5V
12 5.0V 10 4.5V IDD (mA) 4.0V 8 3.5V 6 3.2V 4 3.0V
2 2.5V 0 4 6 8 10
2.7V
12
14
16
18
20
22
24
26
F OSC (M Hz )
FIGURE 22-2:
16
MAXIMUM IDD vs. FOSC OVER VDD (HS MODE)
5.5V
14
Typical: statistical mean @ 25C Maximum: mean + 3 (-40C to 125C) Minimum: mean - 3 (-40C to 125C)
5.0V
12 4.5V 10 4.0V IDD (mA) 3.5V 8
3.2V 6 3.0V 4 2.7V 2 2.5V 0 4 6 8 10 12 14 16 18 20 22 24 26 F OSC (M Hz )
2001 Microchip Technology Inc.
DS39026C-page 263
PIC18CXX2
FIGURE 22-3:
25
TYPICAL IDD vs. FOSC OVER VDD (HS/PLL MODE)
20
Typical: statistical mean @ 25C Maximum: mean + 3 (-40C to 125C) Minimum: mean - 3 (-40C to 125C)
15 IDD (mA) 5.5V 5.0V 10 4.5V 4.0V 3.5V 3.0V 5 2.5V
0 4 5 6 7 FOSC (MHz) 8 9 10
FIGURE 22-4:
25
MAXIMUM IDD vs. FOSC OVER VDD (HS/PLL MODE)
20
Typical: statistical mean @ 25C Maximum: mean + 3 (-40C to 125C) Minimum: mean - 3 (-40C to 125C)
5.5V 5.0V
15 IDD (mA) 4.5V 4.0V 10 3.5V 3.0V
5
2.5V
0 4 5 6 7 FOSC (MHz) 8 9 10
DS39026C-page 264
2001 Microchip Technology Inc.
PIC18CXX2
FIGURE 22-5:
1.0 5.5V
TYPICAL IDD vs. FOSC OVER VDD (XT MODE)
0.8
Typical: statistical mean @ 25C Maximum: mean + 3 (-40C to 125C) Minimum: mean - 3 (-40C to 125C)
5.0V 0.6 IDD (mA)
4.5V 0.4 4.0V
0.2
3.5V 3.0V 2.5V
0.0 0.0 0.5 1.0 1.5 2.0 FOSC (MHz) 2.5 3.0 3.5 4.0
FIGURE 22-6:
2.5
MAXIMUM IDD vs. FOSC OVER VDD (XT MODE)
5.5V 2.0
Typical: statistical mean @ 25C Maximum: mean + 3 (-40C to 125C) Minimum: mean - 3 (-40C to 125C)
5.0V
4.5V 1.5 IDD (mA) 4.0V
3.5V 1.0 3.0V 2.5V 0.5
0.0 0.0 0.5 1.0 1.5 2.0 FOSC (MHz) 2.5 3.0 3.5 4.0
2001 Microchip Technology Inc.
DS39026C-page 265
PIC18CXX2
FIGURE 22-7:
200
TYPICAL IDD vs. FOSC OVER VDD (LP MODE)
180
Typical: statistical mean @ 25C Maximum: mean + 3 (-40C to 125C) Minimum: mean - 3 (-40C to 125C)
160
140
5.5V
120 IDD (uA)
5.0V
100
4.5V
80
4.0V 3.5V 3.0V 2.5V
60
40
20
0 20 30 40 50 60 FOSC (kHz) 70 80 90 100
FIGURE 22-8:
300
MAXIMUM IDD vs. FOSC OVER VDD (LP MODE)
250
Typical: statistical mean @ 25C Maximum: mean + 3 (-40C to 125C) Minimum: mean - 3 (-40C to 125C)
200
5.5V
IDD (uA)
5.0V 150 4.5V 4.0V 3.5V 3.0V 50 2.5V
100
0 20 30 40 50 60 FOSC (kHz) 70 80 90 100
DS39026C-page 266
2001 Microchip Technology Inc.
PIC18CXX2
FIGURE 22-9: TYPICAL AND MAXIMUM IDD vs. VDD (TIMER1 AS MAIN OSCILLATOR, 32.768 kHz, C = 47 pF)
300
250
Typical: statistical mean @ 25C Maximum: mean + 3 (-40C to 125C) Minimum: mean - 3 (-40C to 125C)
200 Max (-40C) IDD (uA)
150 Typ (25C)
100
50
0 2.5 3.0 3.5 4.0 VDD (V) 4.5 5.0 5.5
FIGURE 22-10:
AVERAGE FOSC vs. VDD FOR VARIOUS VALUES OF R (RC MODE, C = 20 pF, 25C)
4.0
3.5 3.3k
3.0
2.5 5.1k Freq (MHz) 2.0
1.5 10k 1.0
0.5 100k 0.0 2.5 3.0 3.5 4.0 VDD (V) 4.5 5.0 5.5
2001 Microchip Technology Inc.
DS39026C-page 267
PIC18CXX2
FIGURE 22-11: AVERAGE FOSC vs. VDD FOR VARIOUS VALUES OF R (RC MODE, C = 100 pF, 25C)
1.8
1.6 3.3k 1.4
1.2 5.1k Freq (MHz) 1.0
0.8
0.6 10k 0.4
0.2 100k 0.0 2.5 3.0 3.5 4.0 VDD (V) 4.5 5.0 5.5
FIGURE 22-12:
AVERAGE FOSC vs. VDD FOR VARIOUS VALUES OF R (RC MODE, C = 300 pF, 25C)
1.0
0.9
0.8 3.3k 0.7
0.6 Freq (MHz) 5.1k 0.5
0.4
0.3 10k 0.2
0.1 100k 0.0 2.5 3.0 3.5 4.0 VDD (V) 4.5 5.0 5.5
DS39026C-page 268
2001 Microchip Technology Inc.
PIC18CXX2
FIGURE 22-13:
100.00
IPD vs. VDD (SLEEP MODE, ALL PERIPHERALS DISABLED)
Typical: statistical mean @ 25C Maximum: mean + 3 (-40C to 125C) Minimum: mean - 3 (-40C to 125C)
Max (125C) 10.00
Max (85C) IPD (uA) 1.00
Typ (25C) 0.10
0.01 2.5 3.0 3.5 4.0 VDD (V) 4.5 5.0 5.5
FIGURE 22-14:
150
IBOR vs. VDD OVER TEMPERATURE (BOR ENABLED, VBOR = 2.50V - 2.66V)
125 Maximum RESET current - example only (Depends on osc mode, osc freq, temp, VDD) 100 Device in SLEEP IBOR ( A)
Typical: statistical mean @ 25C Maximum: mean + 3 (-40C to 125C) Minimum: mean - 3 (-40C to 125C)
75 Indeterminate State (May be in RESET or SLEEP 50 MAX IBOR (-40C to 125C) Typ IBOR (25C)
25
0 2.5 3.0 3.5 4.0 VDD (V) 4.5 5.0 5.5
2001 Microchip Technology Inc.
DS39026C-page 269
PIC18CXX2
FIGURE 22-15: TYPICAL AND MAXIMUM ITMR1 vs. VDD OVER TEMPERATURE (-40C TO +125C, TIMER1 WITH OSCILLATOR, XTAL=32 kHZ, C1 AND C2 = 47 pF)
90
80
70
Typical: statistical mean @ 25C Maximum: mean + 3 (-40C to 125C) Minimum: mean - 3 (-40C to 125C)
Max (-40C to 125C)
60 ITMR1OSC ( A)
50 Typ (25C) 40
30
20
10
0 2.5 3.0 3.5 4.0 VDD (V) 4.5 5.0 5.5
FIGURE 22-16:
TYPICAL AND MAXIMUM IWDT vs. VDD OVER TEMPERATURE (WDT ENABLED)
4.0
3.5
3.0
Typical: statistical mean @ 25C Maximum: mean + 3 (-40C to 125C) Minimum: mean - 3 (-40C to 125C)
2.5 IWDT ( A) Maximum (-40C) 2.0
1.5 Typical (25C) 1.0
0.5
0.0 2.5 3.0 3.5 4.0 VDD (V) 4.5 5.0 5.5
DS39026C-page 270
2001 Microchip Technology Inc.
PIC18CXX2
FIGURE 22-17:
60
TYPICAL, MINIMUM AND MAXIMUM WDT PERIOD vs. VDD (-40C TO +125C)
50
Typical: statistical mean @ 25C Maximum: mean + 3 (-40C to 125C) Minimum: mean - 3 (-40C to 125C)
40 WDT Period (ms)
Max (125C) 30
20
Typ (25C)
Min (-40C) 10
0 2.5 3.0 3.5 4.0 VDD (V) 4.5 5.0 5.5
FIGURE 22-18:
50
ILVD vs. VDD OVER TEMPERATURE (LVD ENABLED, VLVD = 3.0V - 3.2V)
45 Max (-40C to 125C)
40
Max (-40C to 125C)
35
Typ (25C)
Typ (25C)
30 ILVD ( A)
25
Typical: statistical mean @ 25C Maximum: mean + 3 (-40C to 125C) Minimum: mean - 3 (-40C to 125C)
LVDIF is unknown
20
15 LVDIF can be cleared by firmware
10
LVDIF is set by hardware
5
0 2.5 3.0 3.5 4.0 VDD (V) 4.5 5.0 5.5
2001 Microchip Technology Inc.
DS39026C-page 271
PIC18CXX2
FIGURE 22-19: ILVD vs. VDD OVER TEMPERATURE (LVD ENABLED, VLVD = 4.5V - 4.78V)
45 Max (125C) Max (125C)
40
Typ (25C) 35
Typ (25C)
30
ILVD ( A)
25
Typical: statistical mean @ 25C Maximum: mean + 3 (-40C to 125C) Minimum: mean - 3 (-40C to 125C)
LVDIF is unknown LVDIF can be cleared by firmware
20
15 LVDIF is set by hardware 10
5
0 2.5 3.0 3.5 4.0 VDD (V) 4.5 5.0 5.5
FIGURE 22-20:
TYPICAL, MINIMUM AND MAXIMUM VOH vs. IOH (VDD = 5V, -40C TO +125C)
5.0
4.5 Max (-40C) Typ (25C) Min (125C)
4.0
3.5
3.0 VOH (V)
2.5
2.0
1.5
Typical: statistical mean @ 25C Maximum: mean + 3 (-40C to 125C) Minimum: mean - 3 (-40C to 125C)
1.0
0.5
0.0 0 5 10 IOH (-mA) 15 20 25
DS39026C-page 272
2001 Microchip Technology Inc.
PIC18CXX2
FIGURE 22-21:
3.0
TYPICAL, MINIMUM AND MAXIMUM VOH vs. IOH (VDD = 3V, -40C TO +125C)
2.5 Max (-40C) Typ (25C) 2.0 Min (125C)
Typical: statistical mean @ 25C Maximum: mean + 3 (-40C to 125C) Minimum: mean - 3 (-40C to 125C)
VOH (V)
1.5
1.0
0.5
0.0 0 5 10 IOH (-mA) 15 20 25
FIGURE 22-22:
1.4
TYPICAL AND MAXIMUM VOL vs. IOL (VDD = 5V, -40C TO +125C)
1.2
1.0
Typical: statistical mean @ 25C Maximum: mean + 3 (-40C to 125C) Minimum: mean - 3 (-40C to 125C)
Max (-40C to 125C)
0.8 VOL (V) 0.6 Typ (25C) 0.4 0.2 0.0 0 5 10 IOL (mA) 15 20 25
2001 Microchip Technology Inc.
DS39026C-page 273
PIC18CXX2
FIGURE 22-23:
2.4 2.2 2.0 1.8 1.6 1.4 VOL (V) 1.2 1.0 0.8 0.6 0.4 0.2 0.0 0 5 10 IOL (mA) 15 20 25
TYPICAL AND MAXIMUM VOL vs. IOL (VDD = 3V, -40C TO +125C)
Typical: statistical mean @ 25C Maximum: mean + 3 (-40C to 125C) Minimum: mean - 3 (-40C to 125C)
Max (-40C to 125C)
Typ (25C)
FIGURE 22-24:
4.0
MINIMUM AND MAXIMUM VIN vs. VDD (ST INPUT, -40C TO +125C)
3.5
Typical: statistical mean @ 25C Maximum: mean + 3 (-40C to 125C) Minimum: mean - 3 (-40C to 125C)
VIH Max (125C)
3.0 VIH Min (-40C) 2.5
VIN (V)
2.0
VIL Max (-40C)
1.5 VIL Min (125C)
1.0
0.5
0.0 2.5 3.0 3.5 4.0 VDD (V) 4.5 5.0 5.5
DS39026C-page 274
2001 Microchip Technology Inc.
PIC18CXX2
FIGURE 22-25:
2.0
MINIMUM AND MAXIMUM VIN vs. VDD, (TTL INPUT, -40C TO +125C)
1.8
1.6
Typical: statistical mean @ 25C Maximum: mean + 3 (-40C to 125C) Minimum: mean - 3 (-40C to 125C)
1.4 Max VTH (-40C) 1.2 VIN (V)
1.0 Min VTH (125C)
0.8
0.6
0.4
0.2
0.0 2.5 3.0 3.5 4.0 VDD (V) 4.5 5.0 5.5
FIGURE 22-26:
MINIMUM AND MAXIMUM VIN vs. VDD (I2C INPUT, -40C TO +125C)
4.0 Min VIH (-40C)
Max VIH (125C) 3.5
3.0
Typical: statistical mean @ 25C Maximum: mean + 3 (-40C to 125C) Minimum: mean - 3 (-40C to 125C)
2.5
VIN (V)
2.0
1.5
1.0
Min VIL (-40C) 0.5
Max VIL (125C)
0.0 2.5 3.0 3.5 4.0 VDD (V) 4.5 5.0 5.5
2001 Microchip Technology Inc.
DS39026C-page 275
PIC18CXX2
NOTES:
DS39026C-page 276
2001 Microchip Technology Inc.
PIC18CXX2
23.0
23.1
PACKAGING INFORMATION
Package Marking Information
28-Lead PDIP (Skinny DIP) XXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXX YYWWNNN
Example PIC18C242-I/SP 0117017
28-Lead SOIC XXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXXXX YYWWNNN
Example PIC18C242-E/SO 0110017
Legend:
XX...X YY WW NNN
Customer specific information* Year code (last 2 digits of calendar year) Week code (week of January 1 is week `01') Alphanumeric traceability code
Note:
In the event the full Microchip part number cannot be marked on one line, it will be carried over to the next line thus limiting the number of available characters for customer specific information.
*
Standard PICmicro device marking consists of Microchip part number, year code, week code, and traceability code. For PICmicro device marking beyond this, certain price adders apply. Please check with your Microchip Sales Office. For QTP devices, any special marking adders are included in QTP price.
2001 Microchip Technology Inc.
DS39026C-page 277
PIC18CXX2
Package Marking Information (Cont'd)
40-Lead PDIP XXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXXX YYWWNNN
Example PIC18C442-I/P 0112017
28- and 40-Lead JW (CERDIP) XXXXXXXXXXX XXXXXXXXXXX XXXXXXXXXXX YYWWNNN
Example PIC18C452 -I/JW 0115017
44-Lead TQFP
Example
XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX YYWWNNN
PIC18C442 -E/PT 0120017
44-Lead PLCC
Example
XXXXXXXXXX XXXXXXXXXX XXXXXXXXXX YYWWNNN
PIC18C452 -I/L 0120017
DS39026C-page 278
2001 Microchip Technology Inc.
PIC18CXX2
23.2 Package Details
The following sections give the technical details of the packages.
28-Lead Skinny Plastic Dual In-line (SP) - 300 mil (PDIP)
E1
D
2 n 1
E
A2 A L A1 B1 B p
c eB
Units Number of Pins Pitch Top to Seating Plane Molded Package Thickness Base to Seating Plane Shoulder to Shoulder Width Molded Package Width Overall Length Tip to Seating Plane Lead Thickness Upper Lead Width Lower Lead Width Overall Row Spacing Mold Draft Angle Top Mold Draft Angle Bottom Dimension Limits n p A A2 A1 E E1 D L c B1 B eB MIN
INCHES* NOM 28 .100 .140 .125 .015 .300 .275 1.345 .125 .008 .040 .016 .320 5 5 .310 .285 1.365 .130 .012 .053 .019 .350 10 10 .325 .295 1.385 .135 .015 .065 .022 .430 15 15 .150 .130 .160 .135 MAX MIN
MILLIMETERS NOM 28 2.54 3.56 3.18 0.38 7.62 6.99 34.16 3.18 0.20 1.02 0.41 8.13 5 5 7.87 7.24 34.67 3.30 0.29 1.33 0.48 8.89 10 10 8.26 7.49 35.18 3.43 0.38 1.65 0.56 10.92 15 15 3.81 3.30 4.06 3.43 MAX
* Controlling Parameter Significant Characteristic Notes: Dimension D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed .010" (0.254mm) per side. JEDEC Equivalent: MO-095
Drawing No. C04-070
2001 Microchip Technology Inc.
DS39026C-page 279
PIC18CXX2
28-Lead Plastic Small Outline (SO) - Wide, 300 mil (SOIC)
E E1 p
D
B n h 45 c A Units Dimension Limits n p A A2 A1 E E1 D h L c B L A1 INCHES* NOM 28 .050 .099 .091 .008 .407 .295 .704 .020 .033 4 .011 .017 12 12 MILLIMETERS NOM 28 1.27 2.36 2.50 2.24 2.31 0.10 0.20 10.01 10.34 7.32 7.49 17.65 17.87 0.25 0.50 0.41 0.84 0 4 0.23 0.28 0.36 0.42 0 12 0 12 A2 2 1
MIN
MAX
MIN
MAX
Number of Pins Pitch Overall Height Molded Package Thickness Standoff Overall Width Molded Package Width Overall Length Chamfer Distance Foot Length Foot Angle Top Lead Thickness Lead Width Mold Draft Angle Top Mold Draft Angle Bottom * Controlling Parameter Significant Characteristic
.093 .088 .004 .394 .288 .695 .010 .016 0 .009 .014 0 0
.104 .094 .012 .420 .299 .712 .029 .050 8 .013 .020 15 15
2.64 2.39 0.30 10.67 7.59 18.08 0.74 1.27 8 0.33 0.51 15 15
Notes: Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed .010" (0.254mm) per side. JEDEC Equivalent: MS-013 Drawing No. C04-052
DS39026C-page 280
2001 Microchip Technology Inc.
PIC18CXX2
40-Lead Plastic Dual In-line (P) - 600 mil (PDIP)
E1
D
n E
2 1
A c eB Units Dimension Limits n p INCHES* NOM 40 .100 .175 .150 A1 B1 B p MILLIMETERS NOM 40 2.54 4.06 4.45 3.56 3.81 0.38 15.11 15.24 13.46 13.84 51.94 52.26 3.05 3.30 0.20 0.29 0.76 1.27 0.36 0.46 15.75 16.51 5 10 5 10
A2 L
MIN
MAX
MIN
MAX
Number of Pins Pitch Top to Seating Plane A .160 .190 Molded Package Thickness A2 .140 .160 Base to Seating Plane A1 .015 Shoulder to Shoulder Width E .595 .600 .625 Molded Package Width E1 .530 .545 .560 Overall Length D 2.045 2.058 2.065 Tip to Seating Plane L .120 .130 .135 c Lead Thickness .008 .012 .015 Upper Lead Width B1 .030 .050 .070 Lower Lead Width B .014 .018 .022 Overall Row Spacing eB .620 .650 .680 Mold Draft Angle Top 5 10 15 Mold Draft Angle Bottom 5 10 15 * Controlling Parameter Significant Characteristic Notes: Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed .010" (0.254mm) per side. JEDEC Equivalent: MO-011 Drawing No. C04-016
4.83 4.06 15.88 14.22 52.45 3.43 0.38 1.78 0.56 17.27 15 15
2001 Microchip Technology Inc.
DS39026C-page 281
PIC18CXX2
28-Lead Ceramic Dual In-line with Window (JW) - 600 mil (CERDIP)
E1
W
D
2 n 1
E
A c eB A1 B1 B INCHES* NOM 28 .100 .210 .160 .038 .600 .520 1.460 .138 .010 .058 .020 .660 .280 p MILLIMETERS NOM 28 2.54 4.95 5.33 3.94 4.06 0.38 0.95 15.11 15.24 13.06 13.21 36.32 37.08 3.18 3.49 0.20 0.25 1.27 1.46 0.41 0.51 15.49 16.76 6.86 7.11
A2 L
Number of Pins Pitch Top to Seating Plane Ceramic Package Height Standoff Shoulder to Shoulder Width Ceramic Pkg. Width Overall Length Tip to Seating Plane Lead Thickness Upper Lead Width Lower Lead Width Overall Row Spacing Window Diameter * Controlling Parameter Significant Characteristic JEDEC Equivalent: MO-103 Drawing No. C04-013
Units Dimension Limits n p A A2 A1 E E1 D L c B1 B eB W
MIN
MAX
MIN
MAX
.195 .155 .015 .595 .514 1.430 .125 .008 .050 .016 .610 .270
.225 .165 .060 .625 .526 1.490 .150 .012 .065 .023 .710 .290
5.72 4.19 1.52 15.88 13.36 37.85 3.81 0.30 1.65 0.58 18.03 7.37
DS39026C-page 282
2001 Microchip Technology Inc.
PIC18CXX2
40-Lead Ceramic Dual In-line with Window (JW) - 600 mil (CERDIP)
E1
W
D
n E
2 1
A2 c eB Units Dimension Limits n p A A2 A1 E E1 D L c B1 B eB W INCHES* NOM 40 .100 .205 .160 .045 .600 .520 2.050 .140 .011 .053 .020 .660 .350 B1 B p MILLIMETERS NOM 40 2.54 4.70 5.21 3.94 4.06 0.76 1.14 15.11 15.24 13.06 13.21 51.82 52.07 3.43 3.56 0.20 0.28 1.27 1.33 0.41 0.51 15.49 16.76 8.64 8.89 A1
A
MIN
MAX
MIN
MAX
Number of Pins Pitch Top to Seating Plane Ceramic Package Height Standoff Shoulder to Shoulder Width Ceramic Pkg. Width Overall Length Tip to Seating Plane Lead Thickness Upper Lead Width Lower Lead Width Overall Row Spacing Window Diameter * Controlling Parameter Significant Characteristic JEDEC Equivalent: MO-103 Drawing No. C04-014
.185 .155 .030 .595 .514 2.040 .135 .008 .050 .016 .610 .340
.225 .165 .060 .625 .526 2.060 .145 .014 .055 .023 .710 .360
5.72 4.19 1.52 15.88 13.36 52.32 3.68 0.36 1.40 0.58 18.03 9.14
2001 Microchip Technology Inc.
DS39026C-page 283
PIC18CXX2
44-Lead Plastic Thin Quad Flatpack (PT) 10x10x1 mm Body, 1.0/0.10 mm Lead Form (TQFP)
E E1 #leads=n1 p
D1
D
B n
2 1
CH x 45 A
c
L A1 (F) Units Dimension Limits n p n1 A A2 A1 L (F) E D E1 D1 c B CH INCHES NOM 44 .031 11 .043 .039 .004 .024 .039 3.5 .472 .472 .394 .394 .006 .015 .035 10 10 MILLIMETERS* NOM 44 0.80 11 1.00 1.10 0.95 1.00 0.05 0.10 0.45 0.60 1.00 0 3.5 11.75 12.00 11.75 12.00 9.90 10.00 9.90 10.00 0.09 0.15 0.30 0.38 0.64 0.89 5 10 5 10 A2
MIN
MAX
MIN
MAX
Number of Pins Pitch Pins per Side Overall Height Molded Package Thickness Standoff Foot Length Footprint (Reference) Foot Angle Overall Width Overall Length Molded Package Width Molded Package Length Lead Thickness Lead Width Pin 1 Corner Chamfer Mold Draft Angle Top Mold Draft Angle Bottom * Controlling Parameter Significant Characteristic
.039 .037 .002 .018 0 .463 .463 .390 .390 .004 .012 .025 5 5
.047 .041 .006 .030 7 .482 .482 .398 .398 .008 .017 .045 15 15
1.20 1.05 0.15 0.75 7 12.25 12.25 10.10 10.10 0.20 0.44 1.14 15 15
Notes: Dimensions D1 and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed .010" (0.254mm) per side. JEDEC Equivalent: MS-026 Drawing No. C04-076
DS39026C-page 284
2001 Microchip Technology Inc.
PIC18CXX2
44-Lead Plastic Leaded Chip Carrier (L) - Square (PLCC)
E E1 #leads=n1
D1 D
n12 CH2 x 45 CH1 x 45 A3 A2
35
A B1 B p D2
c E2 Units Dimension Limits n p INCHES* NOM 44 .050 11 .165 .173 .145 .153 .020 .028 .024 .029 .040 .045 .000 .005 .685 .690 .685 .690 .650 .653 .650 .653 .590 .620 .590 .620 .008 .011 .026 .029 .013 .020 0 5 0 5
A1
MIN
MAX
MIN
Number of Pins Pitch Pins per Side n1 Overall Height A .180 Molded Package Thickness A2 .160 Standoff A1 .035 Side 1 Chamfer Height A3 .034 Corner Chamfer 1 CH1 .050 Corner Chamfer (others) CH2 .010 Overall Width E .695 Overall Length D .695 Molded Package Width E1 .656 Molded Package Length D1 .656 Footprint Width E2 .630 Footprint Length D2 .630 c Lead Thickness .013 Upper Lead Width B1 .032 B .021 Lower Lead Width Mold Draft Angle Top 10 Mold Draft Angle Bottom 10 * Controlling Parameter Significant Characteristic Notes: Dimensions D and E1 do not include mold flash or protrusions. Mold flash or protrusions shall not exceed .010" (0.254mm) per side. JEDEC Equivalent: MO-047 Drawing No. C04-048
MILLIMETERS NOM 44 1.27 11 4.19 4.39 3.68 3.87 0.51 0.71 0.61 0.74 1.02 1.14 0.00 0.13 17.40 17.53 17.40 17.53 16.51 16.59 16.51 16.59 14.99 15.75 14.99 15.75 0.20 0.27 0.66 0.74 0.33 0.51 0 5 0 5
MAX
4.57 4.06 0.89 0.86 1.27 0.25 17.65 17.65 16.66 16.66 16.00 16.00 0.33 0.81 0.53 10 10
2001 Microchip Technology Inc.
DS39026C-page 285
PIC18CXX2
NOTES:
DS39026C-page 286
2001 Microchip Technology Inc.
PIC18CXX2
APPENDIX A: REVISION HISTORY APPENDIX B:
Revision A (July 1999)
Original data sheet for PIC18CXX2 family.
DEVICE DIFFERENCES
The differences between the devices listed in this data sheet are shown in Table 1.
Revision B (March 2001)
Added DC and (Section 22.0). AC characteristics graphs
TABLE 1:
DEVICE DIFFERENCES
Feature PIC18C242 16 512 5 No 28-pin DIP 28-pin SOIC 28-pin JW PIC18C252 32 1536 5 No 28-pin DIP 28-pin SOIC 28-pin JW PIC18C442 16 512 8 Yes 40-pin DIP 44-pin PLCC 44-pin TQFP 40-pin JW PIC18C452 32 1536 8 Yes 40-pin DIP 44-pin PLCC 44-pin TQFP 40-pin JW
Program Memory (Kbytes) Data Memory (Bytes) A/D Channels Parallel Slave Port (PSP) Package Types
2001 Microchip Technology Inc.
DS39026C-page 287
PIC18CXX2
APPENDIX C: CONVERSION CONSIDERATIONS APPENDIX D: MIGRATION FROM BASELINE TO ENHANCED DEVICES
This appendix discusses the considerations for converting from previous versions of a device to the ones listed in this data sheet. Typically, these changes are due to the differences in the process technology used. An example of this type of conversion is from a PIC16C74A to a PIC16C74B. Not Applicable
This section discusses how to migrate from a Baseline device (i.e., PIC16C5X) to an Enhanced MCU device (i.e., PIC18CXXX). The following are the list of modifications over the PIC16C5X microcontroller family: Not Currently Available
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APPENDIX E: MIGRATION FROM MID-RANGE TO ENHANCED DEVICES APPENDIX F: MIGRATION FROM HIGH-END TO ENHANCED DEVICES
A detailed discussion of the differences between the mid-range MCU devices (i.e., PIC16CXXX) and the enhanced devices (i.e., PIC18CXXX) is provided in AN716, "Migrating Designs from PIC16C74A/74B to PIC18C442." The changes discussed, while device specific, are generally applicable to all mid-range to enhanced device migrations. This Application Note is available as Literature Number DS00716.
A detailed discussion of the migration pathway and differences between the high-end MCU devices (i.e., PIC17CXXX) and the enhanced devices (i.e., PIC18CXXX) is provided in AN726, "PIC17CXXX to PIC18CXXX Migration." This Application Note is available as Literature Number DS00726.
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INDEX
A
A/D ................................................................................... 165 A/D Converter Flag (ADIF Bit) ................................. 167 A/D Converter Interrupt, Configuring ....................... 168 ADCON0 Register .................................................... 165 ADCON1 Register ............................................ 165, 166 ADRES Register .............................................. 165, 167 Analog Port Pins .................................................. 89, 90 Analog Port Pins, Configuring .................................. 170 Associated Registers ............................................... 172 Block Diagram .......................................................... 167 Block Diagram, Analog Input Model ......................... 168 Configuring the Module ............................................ 168 Conversion Clock (TAD) ........................................... 170 Conversion Status (GO/DONE Bit) .......................... 167 Conversions ............................................................. 171 Converter Characteristics ........................................ 261 Equations ................................................................. 169 Sampling Requirements ........................................... 168 Sampling Time ......................................................... 169 Special Event Trigger (CCP) ............................ 110, 171 Timing Diagram ........................................................ 262 Absolute Maximum Ratings ............................................. 235 ACKSTAT ........................................................................ 139 ADCON0 Register ............................................................ 165 GO/DONE Bit ........................................................... 167 ADCON1 Register .................................................... 165, 166 ADDLW ............................................................................ 193 ADDWF ............................................................................ 193 ADDWFC ......................................................................... 194 ADRES Register ...................................................... 165, 167 Analog-to-Digital Converter. See A/D ANDLW ............................................................................ 194 ANDWF ............................................................................ 195 Assembler MPASM Assembler .................................................. 229 PORTB RB3 Pin ............................................................. 81 RB3:RB0 Port Pins ............................................ 81 RB7:RB4 Port Pins ............................................ 80 PORTC (Peripheral Output Override) ........................ 83 PORTD (I/O Mode) .................................................... 85 PORTE (I/O Mode) .................................................... 87 PWM Operation (Simplified) .................................... 112 SSP (SPI Mode) ...................................................... 121 Timer1 ....................................................................... 98 Timer1 (16-bit R/W Mode) ......................................... 98 Timer2 ..................................................................... 102 Timer3 ..................................................................... 104 Timer3 (16-bit R/W Mode) ....................................... 104 USART Asynchronous Receive .................................... 157 Asynchronous Transmit ................................... 155 Watchdog Timer ...................................................... 184 BN .................................................................................... 196 BNC ................................................................................. 197 BNOV .............................................................................. 198 BNZ ................................................................................. 198 BOR. See Brown-out Reset BOV ................................................................................. 201 BRA ................................................................................. 199 BRG. See Baud Rate Generator Brown-out Reset (BOR) ............................................. 26, 179 Timing Diagram ....................................................... 248 BSF .................................................................................. 199 BTFSC ............................................................................. 200 BTFSS ............................................................................. 200 BTG ................................................................................. 201 Bus Collision During a Repeated START Condition ........ 147 Bus Collision During a START Condition ........................ 145 Bus Collision During a STOP Condition .......................... 148 BZ .................................................................................... 202
B
Baud Rate Generator ....................................................... 136 BC .................................................................................... 195 BCF .................................................................................. 196 BF .................................................................................... 139 Block Diagrams A/D Converter .......................................................... 167 Analog Input Model .................................................. 168 Baud Rate Generator ............................................... 136 Capture Mode Operation ......................................... 109 Compare Mode Operation ....................................... 110 Low Voltage Detect External Reference Source .............................. 174 Internal Reference Source ............................... 174 MSSP I2C Mode .......................................................... 128 SPI Mode ......................................................... 121 On-Chip Reset Circuit ................................................ 25 Parallel Slave Port (PORTD and PORTE) ................. 90 PORTA RA3:RA0 and RA5 Port Pins ............................. 77 RA4/T0CKI Pin .................................................. 78 RA6 Pin .............................................................. 78
C
CALL ................................................................................ 202 Capture (CCP Module) .................................................... 109 Associated Registers ............................................... 111 Block Diagram ......................................................... 109 CCP Pin Configuration ............................................ 109 CCPR1H:CCPR1L Registers .................................. 109 Software Interrupt .................................................... 109 Timer1 Mode Selection ............................................ 109 Capture/Compare/PWM (CCP) ....................................... 107 Capture Mode. See Capture CCP1 ....................................................................... 108 CCPR1H Register ........................................... 108 CCPR1L Register ............................................ 108 CCP1CON and CCP2CON Registers ..................... 107 CCP2 ....................................................................... 108 CCPR2H Register ........................................... 108 CCPR2L Register ............................................ 108 Compare Mode. See Compare Interaction of Two CCP Modules ............................. 108 PWM Mode. See PWM Timer Resources ..................................................... 108 Timing Diagram ....................................................... 250 Clocking Scheme ............................................................... 39 CLRF ............................................................................... 203 CLRWDT ......................................................................... 203
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Code Examples 16 x 16 Signed Multiply Routine ................................ 62 16 x 16 Unsigned Multiply Routine ............................ 62 8 x 8 Signed Multiply Routine .................................... 61 8 x 8 Unsigned Multiply Routine ................................ 61 Changing Between Capture Prescalers ................... 109 Fast Register Stack .................................................... 39 Initializing PORTA ...................................................... 77 Initializing PORTB ...................................................... 80 Initializing PORTC ...................................................... 83 Initializing PORTD ...................................................... 85 Initializing PORTE ...................................................... 87 Loading the SSPBUF Register ................................ 122 Saving STATUS, WREG and BSR Registers in RAM ............................................................... 75 Code Protection ....................................................... 179, 186 COMF ............................................................................... 204 Compare (CCP Module) ................................................... 110 Associated Registers ............................................... 111 Block Diagram .......................................................... 110 CCP Pin Configuration ............................................. 110 CCPR1H:CCPR1L Registers ................................... 110 Software Interrupt .................................................... 110 Special Event Trigger ......................... 99, 105, 110, 171 Timer1 Mode Selection ............................................ 110 Configuration Bits ............................................................. 179 Context Saving During Interrupts ....................................... 75 Example Code ........................................................... 75 Conversion Considerations .............................................. 288 CPFSEQ .......................................................................... 204 CPFSGT ........................................................................... 205 CPFSLT ........................................................................... 205
I
I/O Ports ............................................................................. 77 I2C (SSP Module) ............................................................ 128 ACK Pulse ....................................................... 128, 129 Addressing ............................................................... 129 Block Diagram ......................................................... 128 Read/Write Bit Information (R/W Bit) ....................... 129 Reception ................................................................ 129 Serial Clock (RC3/SCK/SCL) ................................... 129 Slave Mode .............................................................. 128 Timing Diagram, Data .............................................. 257 Timing Diagram, START/STOP Bits ........................ 256 Transmission ........................................................... 129 I2C Master Mode Reception ............................................ 139 I2C Master Mode Repeated START Condition ................ 138 I2C Module Acknowledge Sequence Timing .............................. 142 Baud Rate Generator Block Diagram Baud Rate Generator ...................................... 136 BRG Reset Due to SDA Collision ............................ 146 BRG Timing ............................................................. 136 Bus Collision Acknowledge ................................................... 144 Repeated START Condition ............................ 147 Repeated START Condition Timing (Case 1) ................................................... 147 Repeated START Condition Timing (Case 2) ................................................... 147 START Condition ............................................. 145 START Condition Timing ......................... 145, 146 STOP Condition ............................................... 148 STOP Condition Timing (Case 1) .................... 148 STOP Condition Timing (Case 2) .................... 148 Transmit Timing ............................................... 144 Bus Collision Timing ................................................ 144 Clock Arbitration ...................................................... 143 Clock Arbitration Timing (Master Transmit) ............. 143 General Call Address Support ................................. 133 Master Mode 7-bit Reception Timing ....................... 141 Master Mode Operation ........................................... 135 Master Mode START Condition ............................... 137 Master Mode Transmission ..................................... 139 Master Mode Transmit Sequence ............................ 135 Multi-Master Mode ................................................... 144 Repeat START Condition Timing ............................ 138 STOP Condition Receive or Transmit Timing .......... 143 STOP Condition Timing ........................................... 142 Waveforms for 7-bit Reception ................................ 130 Waveforms for 7-bit Transmission ........................... 130 ICEPIC In-Circuit Emulator .............................................. 230 ID Locations ............................................................. 179, 186 INCF ................................................................................ 208 INCFSZ ............................................................................ 209 In-Circuit Serial Programming (ICSP) ...................... 179, 186 Indirect Addressing ............................................................ 51 FSR Register ............................................................. 50 INFSNZ ............................................................................ 209 Instruction Cycle ................................................................ 39 Instruction Flow/Pipelining ................................................. 40 Instruction Format ............................................................ 189
D
Data Memory ...................................................................... 42 General Purpose Registers ........................................ 42 Special Function Registers ........................................ 42 DAW ................................................................................. 206 DC Characteristics ................................................... 237, 240 DECF ............................................................................... 206 DECFSNZ ........................................................................ 207 DECFSZ ........................................................................... 207 Device Differences ........................................................... 287 Direct Addressing ............................................................... 51
E
Electrical Characteristics .................................................. 235 Errata ................................................................................... 5
F
Firmware Instructions ....................................................... 187
G
General Call Address Sequence ...................................... 133 General Call Address Support ......................................... 133 GOTO ............................................................................... 208
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Instruction Set .................................................................. 187 ADDLW .................................................................... 193 ADDWF .................................................................... 193 ADDWFC ................................................................. 194 ANDLW .................................................................... 194 ANDWF .................................................................... 195 BC ............................................................................ 195 BCF .......................................................................... 196 BN ............................................................................ 196 BNC ......................................................................... 197 BNOV ....................................................................... 198 BNZ .......................................................................... 198 BOV ......................................................................... 201 BRA .......................................................................... 199 BSF .......................................................................... 199 BTFSC ..................................................................... 200 BTFSS ..................................................................... 200 BTG .......................................................................... 201 BZ ............................................................................ 202 CALL ........................................................................ 202 CLRF ........................................................................ 203 CLRWDT .................................................................. 203 COMF ...................................................................... 204 CPFSEQ .................................................................. 204 CPFSGT .................................................................. 205 CPFSLT ................................................................... 205 DAW ......................................................................... 206 DECF ....................................................................... 206 DECFSNZ ................................................................ 207 DECFSZ ................................................................... 207 GOTO ...................................................................... 208 INCF ......................................................................... 208 INCFSZ .................................................................... 209 INFSNZ .................................................................... 209 IORLW ..................................................................... 210 IORWF ..................................................................... 210 LFSR ........................................................................ 211 MOVF ....................................................................... 211 MOVFF .................................................................... 212 MOVLB .................................................................... 212 MOVLW ................................................................... 213 MOVWF ................................................................... 213 MULLW .................................................................... 214 MULWF .................................................................... 214 NEGF ....................................................................... 215 NOP ......................................................................... 215 RCALL ..................................................................... 217 RESET ..................................................................... 217 RETFIE .................................................................... 218 RETLW .................................................................... 218 RETURN .................................................................. 219 RLCF ........................................................................ 219 RLNCF ..................................................................... 220 RRCF ....................................................................... 220 RRNCF .................................................................... 221 SETF ........................................................................ 221 SLEEP ..................................................................... 222 SUBFWB .................................................................. 222 SUBLW .................................................................... 223 SUBWF .................................................................... 223 SUBWFB .................................................................. 224 SWAPF .................................................................... 224 TBLRD ..................................................................... 225 TBLWT ..................................................................... 226 TSTFSZ ................................................................... 227 XORLW ................................................................... 227 XORWF ................................................................... 228 Summary Table ....................................................... 190 INT Interrupt (RB0/INT). See Interrupt Sources INTCON Register RBIF Bit ..................................................................... 80 INTCON Registers ............................................................. 65 Inter-Integrated Circuit. See I2C Internal Program Memory Read/Writes ............................................................... 57 Interrupt Sources ....................................................... 63, 179 A/D Conversion Complete ....................................... 168 Capture Complete (CCP) ........................................ 109 Compare Complete (CCP) ...................................... 110 INT0 ........................................................................... 75 Interrupt-on-Change (RB7:RB4 ) ............................... 80 PORTB, on Change ................................................... 75 RB0/INT Pin, External ............................................... 75 SSP Receive/Transmit Complete ............................ 115 TMR0 ......................................................................... 75 TMR0 Overflow .......................................................... 95 TMR1 Overflow .................................... 97, 99, 103, 105 TMR2 to PR2 Match ................................................ 102 TMR2 to PR2 Match (PWM) ............................ 101, 112 USART Receive/Transmit Complete ....................... 149 Interrupts, Enable Bits CCP1 Enable (CCP1IE Bit) ..................................... 109 Interrupts, Flag Bits A/D Converter Flag (ADIF Bit) ................................. 167 CCP1 Flag (CCP1IF Bit) .................................. 109, 110 Interrupt-on-Change (RB7:RB4) Flag (RBIF Bit) ....... 80 IORLW ............................................................................. 210 IORWF ............................................................................. 210 IPR Registers ..................................................................... 72
K
KEELOQ Evaluation and Programming Tools ................... 232
L
LFSR ............................................................................... 211 Long Write and Interrupts ............................................................ 59 Operation ................................................................... 58 Sequence of Events .................................................. 58 Unexpected Termination ........................................... 59 Low Voltage Detect ......................................................... 173 Block Diagrams External Reference Source ............................. 174 Internal Reference Source ............................... 174 Converter Characteristics ........................................ 242 Effects of a RESET .................................................. 177 Operation ................................................................. 176 Current Consumption ...................................... 177 During SLEEP ................................................. 177 Reference Voltage Set Point ........................... 177 LVD. See Low Voltage Detect.
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M
Master Synchronous Serial Port (MSSP). See SSP. Memory Organization Data Memory ............................................................. 42 Program Memory ....................................................... 35 Migration from Baseline to Enhanced Devices ................ 288 MOVF ............................................................................... 211 MOVFF ............................................................................. 212 MOVLB ............................................................................. 212 MOVLW ............................................................................ 213 MOVWF ........................................................................... 213 MPLAB C17 and MPLAB C18 C Compilers ..................... 229 MPLAB ICD In-Circuit Debugger ...................................... 231 MPLAB ICE High Performance Universal In-Circuit Emulator with MPLAB IDE ........................ 230 MPLAB Integrated Development Environment Software .............................................. 229 MPLINK Object Linker/MPLIB Object Librarian ............... 230 MULLW ............................................................................ 214 Multi-Master Mode ........................................................... 144 MULWF ............................................................................ 214 PICSTART Plus Entry Level Development System ......... 231 PIE Registers ..................................................................... 70 Pin Functions MCLR/VPP ........................................................... 10, 13 OSC1/CLKIN ....................................................... 10, 13 OSC2/CLKOUT ................................................... 10, 13 RA0/AN0 .............................................................. 10, 13 RA1/AN1 .............................................................. 10, 13 RA2/AN2 .............................................................. 10, 13 RA3/AN3/VREF ..................................................... 10, 13 RA4/T0CKI .......................................................... 10, 13 RA5/AN4/SS ........................................................ 10, 13 RB0/INT ............................................................... 11, 14 RB1 ...................................................................... 11, 14 RB2 ...................................................................... 11, 14 RB3 ...................................................................... 11, 14 RB4 ...................................................................... 11, 14 RB5 ...................................................................... 11, 14 RB6 ...................................................................... 11, 14 RB7 ...................................................................... 11, 14 RC0/T1OSO/T1CKI ............................................. 12, 15 RC1/T1OSI/CCP2 ................................................ 12, 15 RC2/CCP1 ........................................................... 12, 15 RC3/SCK/SCL ..................................................... 12, 15 RC4/SDI/SDA ...................................................... 12, 15 RC5/SDO ............................................................. 12, 15 RC6/TX/CK .......................................................... 12, 15 RC7/RX/DT .......................................................... 12, 15 RD0/PSP0 ................................................................. 16 RD1/PSP1 ................................................................. 16 RD2/PSP2 ................................................................. 16 RD3/PSP3 ................................................................. 16 RD4/PSP4 ................................................................. 16 RD5/PSP5 ................................................................. 16 RD6/PSP6 ................................................................. 16 RD7/PSP7 ................................................................. 16 RE0/RD/AN5 .............................................................. 16 RE1/WR/AN6 ............................................................. 16 RE2/CS/AN7 .............................................................. 16 VDD ...................................................................... 12, 16 VSS ...................................................................... 12, 16 PIR Registers ..................................................................... 68 Pointer, FSR ...................................................................... 50 POR. See Power-on Reset. PORTA Associated Registers ................................................. 79 Initialization ................................................................ 77 PORTA Register ........................................................ 77 RA3:RA0 and RA5 Port Pins ..................................... 77 RA4/T0CKI Pin .......................................................... 78 RA6 Pin ..................................................................... 78 TRISA Register .......................................................... 77 PORTB Associated Registers ................................................. 82 Initialization ................................................................ 80 PORTB Register ........................................................ 80 RB0/INT Pin, External ................................................ 75 RB3 Pin ..................................................................... 81 RB3:RB0 Port Pins .................................................... 81 RB7:RB4 Interrupt-on-Change Flag (RBIF Bit) .......... 80 RB7:RB4 Port Pins .................................................... 80 TRISB Register .......................................................... 80
N
NEGF ............................................................................... 215 NOP ................................................................................. 215
O
On-Chip Reset Circuit Block Diagram ............................................................ 25 OPCODE Field Descriptions ............................................ 188 OPTION_REG Register PS2:PS0 Bits ............................................................. 95 PSA Bit ....................................................................... 95 T0CS Bit ..................................................................... 95 T0SE Bit ..................................................................... 95 Oscillator Configuration .................................................... 179 Oscillator Configurations .................................................... 17 HS .............................................................................. 17 HS + PLL .................................................................... 17 LP ............................................................................... 17 RC ........................................................................ 17, 18 RCIO .......................................................................... 17 XT .............................................................................. 17 Oscillator, Timer1 ......................................... 97, 99, 103, 105 Oscillator, WDT ................................................................ 183
P
Packaging ........................................................................ 277 Parallel Slave Port (PSP) ............................................. 85, 90 Associated Registers ................................................. 91 Block Diagram ............................................................ 90 RE0/RD/AN5 Pin .................................................. 89, 90 RE1/WR/AN6 Pin ................................................. 89, 90 RE2/CS/AN7 Pin .................................................. 89, 90 Read Waveforms ....................................................... 91 Select (PSPMODE Bit) ........................................ 85, 90 Timing Diagram ........................................................ 251 Write Waveforms ....................................................... 90 PICDEM 1 Low Cost PICmicro Demonstration Board ............................................... 231 PICDEM 17 Demonstration Board ................................... 232 PICDEM 2 Low Cost PIC16CXX Demonstration Board ............................................... 231 PICDEM 3 Low Cost PIC16CXXX Demonstration Board ............................................... 232
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PORTC Associated Registers ................................................. 84 Block Diagram (Peripheral Output Override) ............. 83 Initialization .......................................................... 83, 85 PORTC Register ........................................................ 83 RC3/SCK/SCL Pin ................................................... 129 RC7/RX/DT Pin ........................................................ 151 TRISC Register .................................................. 83, 149 PORTD .............................................................................. 90 Associated Registers ................................................. 86 Block Diagram (I/O Mode) ......................................... 85 Parallel Slave Port (PSP) Function ............................ 85 PORTD Register ........................................................ 85 TRISD Register .......................................................... 85 PORTE Analog Port Pins .................................................. 89, 90 Associated Registers ................................................. 89 Block Diagram (I/O Mode) ......................................... 87 Initialization ................................................................ 87 PORTE Register ........................................................ 87 PSP Mode Select (PSPMODE Bit) ...................... 85, 90 RE0/RD/AN5 Pin .................................................. 89, 90 RE1/WR/AN6 Pin ................................................. 89, 90 RE2/CS/AN7 Pin .................................................. 89, 90 TRISE Register .................................................... 87, 88 Postscaler, WDT Assignment (PSA Bit) ................................................ 95 Rate Select (PS2:PS0 Bits) ....................................... 95 Switching Between Timer0 and WDT ........................ 95 Power-down Mode. See SLEEP. Power-on Reset (POR) .............................................. 26, 179 Oscillator Start-up Timer (OST) ......................... 26, 179 Power-up Timer (PWRT) ................................... 26, 179 Time-out Sequence .................................................... 26 Time-out Sequence on Power-up ........................ 32, 33 Timing Diagram ........................................................ 248 Prescaler, Capture ........................................................... 109 Prescaler, Timer0 ............................................................... 95 Assignment (PSA Bit) ................................................ 95 Rate Select (PS2:PS0 Bits) ....................................... 95 Switching Between Timer0 and WDT ........................ 95 Prescaler, Timer1 ............................................................... 98 Prescaler, Timer2 ............................................................. 112 PRO MATE II Universal Programmer .............................. 231 Product Identification System .......................................... 301 Program Counter PCL Register .............................................................. 39 PCLATH Register ...................................................... 39 Program Memory ............................................................... 35 Interrupt Vector .......................................................... 35 RESET Vector ............................................................ 35 Program Verification ........................................................ 186 Programming, Device Instructions ................................... 187 PSP.See Parallel Slave Port. Pulse Width Modulation. See PWM (CCP Module). PWM (CCP Module) ........................................................ 112 Associated Registers ............................................... 113 Block Diagram .......................................................... 112 CCPR1H:CCPR1L Registers ................................... 112 Duty Cycle ................................................................ 112 Example Frequencies/Resolutions .......................... 113 Output Diagram ........................................................ 112 Period ....................................................................... 112 Setup for PWM Operation ........................................ 113 TMR2 to PR2 Match ........................................ 101, 112
Q
Q Clock ............................................................................ 112
R
RAM. See Data Memory. RCALL ............................................................................. 217 RCON Register ............................................................ 53, 56 RCSTA Register SPEN Bit .................................................................. 149 Register File ....................................................................... 42 Registers ADCON0 (A/D Control 0) ......................................... 165 ADCON1 (A/D Control 1) ......................................... 166 CCP1CON and CCP2CON (Capture/Compare/PWM Control) ................... 107 CONFIG1H (Configuration 1 High) .......................... 180 CONFIG1L (Configuration 1 Low) ........................... 180 CONFIG2H (Configuration 2 High) .......................... 181 CONFIG2L (Configuration 2 Low) ........................... 181 CONFIG3H (Configuration 3 High) .......................... 182 CONFIG4L (Configuration 4 Low) ........................... 182 Flag ...................................................................... 68, 69 INTCON (Interrupt Control) ....................................... 65 INTCON2 (Interrupt Control 2) .................................. 66 INTCON3 (Interrupt Control 3) .................................. 67 IPR1 (Peripheral Interrupt Priority 1) ......................... 72 IPR2 (Peripheral Interrupt Priority 2) ......................... 73 LVDCON (LVD Control) ........................................... 175 PIE2 (Peripheral Interrupt Enable 1) ......................... 70 PIE2 (Peripheral Interrupt Enable 2) ......................... 71 PIR1 (Peripheral Interrupt Request 1) ....................... 68 PIR2 (Peripheral Interrupt Request 2) ....................... 69 RCON (Register Control) ........................................... 74 RCON (RESET Control) ...................................... 53, 56 RCSTA (Receive Status and Control) ..................... 150 SSPCON1 (SSP Control 1) ..................................... 118 SSPCON2 (SSP Control 2) ..................................... 120 SSPSTAT (SSP Status) .......................................... 116 STATUS .................................................................... 52 STKPTR (Stack Pointer) ............................................ 38 Summary ................................................................... 46 T0CON (Timer0 Control) ........................................... 93 T1CON (Timer1 Control) ........................................... 97 T2CON (Timer2 Control) ......................................... 101 T3CON (Timer3 Control) ......................................... 103 TRISE ........................................................................ 88 TXSTA (Transmit Status and Control) ..................... 149 RESET ............................................................... 25, 179, 217 Timing Diagram ....................................................... 248 RETFIE ............................................................................ 218 RETLW ............................................................................ 218 RETURN .......................................................................... 219 Revision History ............................................................... 287 RLCF ............................................................................... 219 RLNCF ............................................................................. 220 RRCF ............................................................................... 220 RRNCF ............................................................................ 221
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S
SCI. See USART. SCK .................................................................................. 121 SDI ................................................................................... 121 SDO ................................................................................. 121 Serial Clock, SCK ............................................................. 121 Serial Communication Interface. See USART Serial Data In, SDI ........................................................... 121 Serial Data Out, SDO ....................................................... 121 Serial Peripheral Interface. See SPI SETF ................................................................................ 221 Slave Select Synchronization ........................................... 125 Slave Select, SS .............................................................. 121 SLEEP .............................................................. 179, 185, 222 Software Simulator (MPLAB SIM) .................................... 230 Special Event Trigger. See Compare Special Features of the CPU ............................................ 179 Configuration Registers ................................... 180-182 Special Function Registers ................................................ 42 Map ............................................................................ 45 SPI Master Mode ............................................................ 124 Serial Clock .............................................................. 121 Serial Data In ........................................................... 121 Serial Data Out ........................................................ 121 Slave Select ............................................................. 121 SPI Clock ................................................................. 124 SPI Mode ................................................................. 121 SPI Master/Slave Connection .......................................... 123 SPI Module Master/Slave Connection ......................................... 123 Slave Mode .............................................................. 125 Slave Select Synchronization .................................. 125 Slave Synch Timing ................................................. 125 Slave Timing with CKE = 0 ...................................... 126 Slave Timing with CKE = 1 ...................................... 126 SS .................................................................................... 121 SSP .................................................................................. 115 Block Diagram (SPI Mode) ...................................... 121 I2C Mode. See I2C. SPI Mode ................................................................. 121 Associated Registers ....................................... 127 Block Diagram .................................................. 121 SPI Mode. See SPI. SSPBUF ................................................................... 124 SSPCON1 ................................................................ 118 SSPCON2 Register ................................................. 120 SSPSR ..................................................................... 124 SSPSTAT ................................................................. 116 TMR2 Output for Clock Shift ............................ 101, 102 SSP Module SPI Master Mode ..................................................... 124 SPI Master./Slave Connection ................................. 123 SPI Slave Mode ....................................................... 125 SSPCON1 Register .......................................................... 118 SSPOV ............................................................................. 139 SSPSTAT Register .......................................................... 116 R/W Bit ..................................................................... 129 STATUS Register ............................................................... 52 STKPTR Register ............................................................... 38 SUBFWB .......................................................................... 222 SUBLW ............................................................................ 223 SUBWF ............................................................................ 223 SUBWFB .......................................................................... 224 SWAPF ............................................................................ 224 Synchronous Serial Port. See SSP.
T
TABLAT Register ............................................................... 57 Table Pointer Operations (Table) ...................................... 57 Table Read Operation, Diagram ........................................ 55 Table Write Operation, Diagram ........................................ 55 TBLPTR Register ............................................................... 57 TBLRD ............................................................................. 225 TBLWT ............................................................................. 226 Timer0 ................................................................................ 93 Clock Source Edge Select (T0SE Bit) ....................... 95 Clock Source Select (T0CS Bit) ................................. 95 Overflow Interrupt ...................................................... 95 Prescaler. See Prescaler, Timer0 T0CON Register ........................................................ 93 Timing Diagram ....................................................... 249 Timer1 ................................................................................ 97 Block Diagram ........................................................... 98 Block Diagram (16-bit R/W Mode) ............................. 98 Oscillator .............................................. 97, 99, 103, 105 Overflow Interrupt ................................ 97, 99, 103, 105 Prescaler. .................................................................. 98 Special Event Trigger (CCP) ..................... 99, 105, 110 T1CON Register ........................................................ 97 Timing Diagram ....................................................... 249 TMR1H Register ................................................ 97, 103 TMR1L Register ................................................. 97, 103 Timer2 .............................................................................. 101 Associated Registers ............................................... 102 Block Diagram ......................................................... 102 Postscaler. See Postscaler, Timer2. PR2 Register ................................................... 101, 112 Prescaler. See Prescaler, Timer2. SSP Clock Shift ............................................... 101, 102 T2CON Register ...................................................... 101 TMR2 Register ......................................................... 101 TMR2 to PR2 Match Interrupt .................. 101, 102, 112 Timer3 .............................................................................. 103 Associated Registers ............................................... 105 Block Diagram ......................................................... 104 Block Diagram (16-bit R/W Mode) ........................... 104 T3CON Register ...................................................... 103 Timing Diagrams Acknowledge Sequence Timing .............................. 142 Baud Rate Generator with Clock Arbitration ............ 136 BRG Reset Due to SDA Collision ............................ 146 Bus Collision START Condition Timing ................................. 145 Bus Collision During a Repeated START Condition (Case 1) ........................................... 147 Bus Collision During a Repeated START Condition (Case2) ............................................ 147 Bus Collision During a START Condition (SCL = 0) ......................................................... 146 Bus Collision During a STOP Condition .................. 148 Bus Collision for Transmit and Acknowledge .......... 144 I2C Bus Data ............................................................ 259 I2C Master Mode First START Bit Timing ................ 137 I2C Master Mode Reception Timing ......................... 141 I2C Master Mode Transmission Timing ................... 140 Master Mode Transmit Clock Arbitration ................. 143 Repeat START Condition ........................................ 138 Slave Synchronization ............................................. 125 SPI Mode Timing (Master Mode) SPI Mode Master Mode Timing Diagram ......................... 124 SPI Mode Timing (Slave Mode with CKE = 0) ......... 126 SPI Mode Timing (Slave Mode with CKE = 1) ......... 126 2001 Microchip Technology Inc.
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STOP Condition Receive or Transmit ...................... 143 Time-out Sequence on Power-up ........................ 32, 33 USART Asynchronous Master Transmission ........... 156 USART Asynchronous Reception ............................ 158 USART Synchronous Reception .............................. 161 USART Synchronous Transmission ........................ 160 Wake-up from SLEEP via Interrupt .......................... 186 Timing Diagrams and Specifications ................................ 246 A/D Conversion ........................................................ 262 Brown-out Reset (BOR) ........................................... 248 Capture/Compare/PWM (CCP) ................................ 250 CLKOUT and I/O ...................................................... 247 External Clock .......................................................... 246 I2C Bus Data ............................................................ 257 I2C Bus START/STOP Bits ...................................... 256 Oscillator Start-up Timer (OST) ............................... 248 Parallel Slave Port (PSP) ......................................... 251 Power-up Timer (PWRT) ......................................... 248 RESET ..................................................................... 248 Timer0 and Timer1 ................................................... 249 USART Synchronous Receive (Master/Slave) ................................................. 260 USART SynchronousTransmission (Master/Slave) ................................................. 260 Watchdog Timer (WDT) ........................................... 248 TRISE Register .................................................................. 87 PSPMODE Bit ...................................................... 85, 90 TSTFSZ ........................................................................... 227 Two-Word Instructions Example Cases .......................................................... 41 TXSTA Register BRGH Bit ................................................................. 151 Baud Rate Generator (BRG) ................................... 151 Associated Registers ....................................... 151 Baud Rate Error, Calculating ........................... 151 Baud Rate Formula ......................................... 151 Baud Rates, Asynchronous Mode (BRGH = 0) .............................................. 153 Baud Rates, Asynchronous Mode (BRGH = 1) .............................................. 154 Baud Rates, Synchronous Mode ..................... 152 High Baud Rate Select (BRGH Bit) ................. 151 Sampling ......................................................... 151 RCSTA Register ...................................................... 150 Serial Port Enable (SPEN Bit) ................................. 149 Synchronous Master Mode ...................................... 159 Associated Registers, Reception ..................... 161 Associated Registers, Transmit ....................... 159 Reception ........................................................ 161 Timing Diagram, Synchronous Receive .......... 260 Timing Diagram, Synchronous Transmission ........................................... 260 Transmission ................................................... 160 Associated Registers ............................... 159 Synchronous Slave Mode ........................................ 162 Associated Registers, Receive ........................ 163 Associated Registers, Transmit ....................... 162 Reception ........................................................ 163 Transmission ................................................... 162 TXSTA Register ....................................................... 149
W
Wake-up from SLEEP .............................................. 179, 185 Timing Diagram ....................................................... 186 Using Interrupts ....................................................... 185 Watchdog Timer (WDT) ........................................... 179, 183 Associated Registers ............................................... 184 Block Diagram ......................................................... 184 Postscaler ................................................................ 184 Programming Considerations .................................. 183 RC Oscillator ........................................................... 183 Time-out Period ....................................................... 183 Timing Diagram ....................................................... 248 Waveform for General Call Address Sequence ............... 133 WCOL .............................................................. 137, 139, 142 WCOL Status Flag ........................................................... 137 WDT ................................................................................ 183 WWW, On-Line Support ...................................................... 5
U
Universal Synchronous Asynchronous Receiver Transmitter. See USART. USART ............................................................................. 149 Asynchronous Mode ................................................ 155 Associated Registers, Receive ........................ 158 Associated Registers, Transmit ....................... 156 Master Transmission ....................................... 156 Receive Block Diagram ................................... 157 Receiver ........................................................... 157 Reception ......................................................... 158 Transmit Block Diagram .................................. 155 Transmitter ....................................................... 155
X
XORLW ........................................................................... 227 XORWF ........................................................................... 228
2001 Microchip Technology Inc.
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PIC18CXX2
NOTES:
DS39026C-page 298
2001 Microchip Technology Inc.
PIC18CXX2
ON-LINE SUPPORT
Microchip provides on-line support on the Microchip World Wide Web (WWW) site. The web site is used by Microchip as a means to make files and information easily available to customers. To view the site, the user must have access to the Internet and a web browser, such as Netscape or Microsoft Explorer. Files are also available for FTP download from our FTP site.
Systems Information and Upgrade Hot Line
The Systems Information and Upgrade Line provides system users a listing of the latest versions of all of Microchip's development systems software products. Plus, this line provides information on how customers can receive any currently available upgrade kits.The Hot Line Numbers are: 1-800-755-2345 for U.S. and most of Canada, and 1-480-792-7302 for the rest of the world.
013001
Connecting to the Microchip Internet Web Site
The Microchip web site is available by using your favorite Internet browser to attach to: www.microchip.com The file transfer site is available by using an FTP service to connect to: ftp://ftp.microchip.com The web site and file transfer site provide a variety of services. Users may download files for the latest Development Tools, Data Sheets, Application Notes, User's Guides, Articles and Sample Programs. A variety of Microchip specific business information is also available, including listings of Microchip sales offices, distributors and factory representatives. Other data available for consideration is: * Latest Microchip Press Releases * Technical Support Section with Frequently Asked Questions * Design Tips * Device Errata * Job Postings * Microchip Consultant Program Member Listing * Links to other useful web sites related to Microchip Products * Conferences for products, Development Systems, technical information and more * Listing of seminars and events
2001 Microchip Technology Inc.
DS39026C-page299
PIC18CXX2
READER RESPONSE
It is our intention to provide you with the best documentation possible to ensure successful use of your Microchip product. If you wish to provide your comments on organization, clarity, subject matter, and ways in which our documentation can better serve you, please FAX your comments to the Technical Publications Manager at (480) 792-4150. Please list the following information, and use this outline to provide us with your comments about this Data Sheet. To: RE: Technical Publications Manager Reader Response Total Pages Sent
From: Name Company Address City / State / ZIP / Country Telephone: (_______) _________ - _________ Application (optional): Would you like a reply? Device: PIC18CXX2 Questions: 1. What are the best features of this document? Y N Literature Number: DS39026C FAX: (______) _________ - _________
2. How does this document meet your hardware and software development needs?
3. Do you find the organization of this data sheet easy to follow? If not, why?
4. What additions to the data sheet do you think would enhance the structure and subject?
5. What deletions from the data sheet could be made without affecting the overall usefulness?
6. Is there any incorrect or misleading information (what and where)?
7. How would you improve this document?
8. How would you improve our software, systems, and silicon products?
DS39026C-page300
2001 Microchip Technology Inc.
PIC18CXX2
PIC18CXX2 PRODUCT IDENTIFICATION SYSTEM
To order or obtain information, e.g., on pricing or delivery, refer to the factory or the listed sales office.
PART NO. Device
-
X Temperature Range
/XX Package
XXX Pattern
Examples: a) PIC18LC452 - I/P 301 = Industrial temp., PDIP package, 4 MHz, Extended VDD limits, QTP pattern #301. PIC18LC242 - I/SO = Industrial temp., SOIC package, Extended VDD limits. PIC18C442 - E/P = Extended temp., PDIP package, 40MHz, normal VDD limits.
Device
PIC18CXX2(1), PIC18CXX2T(2); VDD range 4.2V to 5.5V PIC18LCXX2(1), PIC18LCXX2T(2); VDD range 2.5V to 5.5V I E JW PT SO SP P L = = = = = = = = -40C to -40C to +85C +125C (Industrial) (Extended)
b) c)
Temperature Range Package
Windowed CERDIP(3) TQFP (Thin Quad Flatpack) SOIC Skinny plastic dip PDIP PLCC
Note 1: C = Standard Voltage range LC = Wide Voltage Range 2: T = in tape and reel - SOIC, PLCC, and TQFP packages only.
Pattern
QTP, SQTP, Code or Special Requirements (blank otherwise)
3: JW Devices are UV erasable and can be programmed to any device configuration. JW Devices meet the electrical requirement of each oscillator type (including LC devices).
Sales and Support
Data Sheets Products supported by a preliminary Data Sheet may have an errata sheet describing minor operational differences and recommended workarounds. To determine if an errata sheet exists for a particular device, please contact one of the following: 1. 2. 3. Your local Microchip sales office The Microchip Corporate Literature Center U.S. FAX: (480) 792-7277 The Microchip Worldwide Site (www.microchip.com)
Please specify which device, revision of silicon and Data Sheet (include Literature #) you are using. New Customer Notification System Register on our web site (www.microchip.com/cn) to receive the most current information on our products.
2001 Microchip Technology Inc.
DS39026C-page 301
WORLDWIDE SALES AND SERVICE
AMERICAS
Corporate Office
2355 West Chandler Blvd. Chandler, AZ 85224-6199 Tel: 480-792-7200 Fax: 480-792-7277 Technical Support: 480-792-7627 Web Address: http://www.microchip.com
New York
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ASIA/PACIFIC (continued)
Korea
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San Jose
Microchip Technology Inc. 2107 North First Street, Suite 590 San Jose, CA 95131 Tel: 408-436-7950 Fax: 408-436-7955
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Singapore
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Toronto
6285 Northam Drive, Suite 108 Mississauga, Ontario L4V 1X5, Canada Tel: 905-673-0699 Fax: 905-673-6509
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Taiwan
ASIA/PACIFIC
Australia
Microchip Technology Australia Pty Ltd Suite 22, 41 Rawson Street Epping 2121, NSW Australia Tel: 61-2-9868-6733 Fax: 61-2-9868-6755
Austin
Analog Product Sales 8303 MoPac Expressway North Suite A-201 Austin, TX 78759 Tel: 512-345-2030 Fax: 512-345-6085
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Boston
2 Lan Drive, Suite 120 Westford, MA 01886 Tel: 978-692-3848 Fax: 978-692-3821
EUROPE
Denmark
Microchip Technology Denmark ApS Regus Business Centre Lautrup hoj 1-3 Ballerup DK-2750 Denmark Tel: 45 4420 9895 Fax: 45 4420 9910
China - Beijing
Microchip Technology Beijing Office Unit 915 New China Hong Kong Manhattan Bldg. No. 6 Chaoyangmen Beidajie Beijing, 100027, No. China Tel: 86-10-85282100 Fax: 86-10-85282104
Boston
Analog Product Sales Unit A-8-1 Millbrook Tarry Condominium 97 Lowell Road Concord, MA 01742 Tel: 978-371-6400 Fax: 978-371-0050
China - Shanghai
Microchip Technology Shanghai Office Room 701, Bldg. B Far East International Plaza No. 317 Xian Xia Road Shanghai, 200051 Tel: 86-21-6275-5700 Fax: 86-21-6275-5060
France
Arizona Microchip Technology SARL Parc d'Activite du Moulin de Massy 43 Rue du Saule Trapu Batiment A - ler Etage 91300 Massy, France Tel: 33-1-69-53-63-20 Fax: 33-1-69-30-90-79
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Hong Kong
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Germany
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Dayton
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Germany
Analog Product Sales Lochhamer Strasse 13 D-82152 Martinsried, Germany Tel: 49-89-895650-0 Fax: 49-89-895650-22
India
Microchip Technology Inc. India Liaison Office Divyasree Chambers 1 Floor, Wing A (A3/A4) No. 11, O'Shaugnessey Road Bangalore, 560 025, India Tel: 91-80-2290061 Fax: 91-80-2290062
Detroit
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Italy
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Los Angeles
18201 Von Karman, Suite 1090 Irvine, CA 92612 Tel: 949-263-1888 Fax: 949-263-1338
Japan
Microchip Technology Intl. Inc. Benex S-1 6F 3-18-20, Shinyokohama Kohoku-Ku, Yokohama-shi Kanagawa, 222-0033, Japan Tel: 81-45-471- 6166 Fax: 81-45-471-6122
United Kingdom
Arizona Microchip Technology Ltd. 505 Eskdale Road Winnersh Triangle Wokingham Berkshire, England RG41 5TU Tel: 44 118 921 5869 Fax: 44-118 921-5820
01/30/01
Mountain View
Analog Product Sales 1300 Terra Bella Avenue Mountain View, CA 94043-1836 Tel: 650-968-9241 Fax: 650-967-1590
All rights reserved. (c) 2001 Microchip Technology Incorporated. Printed in the USA. 5/01
Printed on recycled paper.
Information contained in this publication regarding device applications and the like is intended through suggestion only and may be superseded by updates. It is your responsibility to ensure that your application meets with your specifications. No representation or warranty is given and no liability is assumed by Microchip Technology Incorporated with respect to the accuracy or use of such information, or infringement of patents or other intellectual property rights arising from such use or otherwise. Use of Microchip's products as critical components in life support systems is not authorized except with express written approval by Microchip. No licenses are conveyed, implicitly or otherwise, except as maybe explicitly expressed herein, under any intellectual property rights. The Microchip logo and name are registered trademarks of Microchip Technology Inc. in the U.S.A. and other countries. All rights reserved. All other trademarks mentioned herein are the property of their respective companies.
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Table of Contents
1.01.0Device Overview .................................................................................................................................................. 7 2.02.0Oscillator Configurations .................................................................................................................................... 17 3.03.0Reset.................................................................................................................................................................. 25 4.04.0Memory Organization......................................................................................................................................... 35 5.05.0Table Reads/Table Writes.................................................................................................................................. 55 6.06.08 X 8 Hardware Multiplier................................................................................................................................... 61 7.07.0Interrupts ............................................................................................................................................................ 63 8.08.0I/O Ports ............................................................................................................................................................. 77 9.09.0Timer0 Module ................................................................................................................................................... 93 10.010.0Timer1 Module ............................................................................................................................................... 97 11.011.0Timer2 Module ............................................................................................................................................. 101 12.012.0Timer3 Module ............................................................................................................................................. 103 13.013.0Capture/Compare/PWM (CCP) Modules ..................................................................................................... 107 14.014.0Master Synchronous Serial Port (MSSP) Module ........................................................................................ 115 15.015.0Addressable Universal Synchronous Asynchronous Receiver Transmitter (USART) ................................. 149 16.016.0Compatible 10-bit Analog-to-Digital Converter (A/D) Module ...................................................................... 165 17.017.0Low Voltage Detect ...................................................................................................................................... 173 18.018.0Special Features of the CPU ....................................................................................................................... 179 19.019.0Instruction Set Summary.............................................................................................................................. 187 20.020.0Development Support .................................................................................................................................. 229 21.021.0Electrical Characteristics.............................................................................................................................. 235 22.022.0DC and AC Characteristics Graphs and Tables........................................................................................... 263 23.023.0Packaging Information ................................................................................................................................. 277 Appendix A:Revision History...................................................................................................................................... 287 Appendix B:Device Differences.................................................................................................................................. 287 Appendix C:Conversion Considerations .................................................................................................................... 288 Appendix D:Migration from Baseline to Enhanced Devices....................................................................................... 288 Appendix E:Migration from Mid-range to Enhanced Devices..................................................................................... 289 Appendix F:Migration from High-end to Enhanced Devices ...................................................................................... 289 INDEX ........................................................................................................................................................................ 291 On-Line Support......................................................................................................................................................... 299 Reader Response ...................................................................................................................................................... 300 PIC18CXX2 Product Identification System ................................................................................................................ 301
2001 Microchip Technology Inc.
DS39026B-page 1

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