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data sheet 100381b september 2001 CX25870/871 video encoder with adaptive flicker filtering and hdtv output conexant?s CX25870/871 is specifically design ed to meet tv out system requirements for the next-generation deskt op pcs, notebook pcs, game consoles and set-top boxes. with pin and software-forward compatib ility to the bt868/869, manufacturers can quickly bring to market new solutions that support adaptive flicker filtering, atsc high-definition television (hdtv) output, and resolutions from 320 x 200 (minimum) to 1024 x 768 (maximum). adaptive flicker filtering is a conexant tech nology in which the encoder looks at the characteristics of the video content on a pixel-by-pixel basis and automatically determines the optimal amount of flicker filtering required. if an end-user wants to work on a spreadsheet while watching a dvd movi e in a window, both the text-intensive application requiring a lot of flicker filt ering and the dvd movie requiring very little flicker filtering can look their best. the amount of flicker filtering and overscan compensation is entirely flexible. the CX25870/871 also provides a 3-wire analog rgb or yp r p b hdtv output. while the encoder is in hdtv output mode, the device will automatically insert horizontal tri-level synchronization pulses and ver tical synchronization broad pulses. the CX25870/871 is compliant with the eia770-3, smpte 274m/293m/296m standards and supports atsc hdtv resolutions including 480p, 720p, and 1080i. all worldwide standard definition output s are supported, in cluding ntsc-m (n. america, taiwan), ntsc-j ( japan), pal-b,d,g,h,i (europe, asia), pal-m (brazil), pal-n (uruguay, paraguay), pal-nc (argentina), pal-60 (china) and secam. the CX25870 and cx25871 are functionally identical, except the cx25871 can output standard definition video with macrovision l evel 7.1.l1 copy protection capability. functional block diagram input demux flicker filter/ scaler fifo 24 video encoder 10-bit 10-bit 10-bit 10-bit xtal osc pll dac mux daca dacb internal reference comp fsadjust xtl_bfo vref bias gen vbias p[23:0] xtalin xtalout clko clki sic sid altaddr hsync* vsync* blank* field reset* sleep slave pa l color space conversion #1 color space conversion #2 dacc dacd timing serial interface clock generation to internal clocks distinguishing features hdtv output mode (patents pending) ? compliant with eia770-3 and smpte274m/293m/296m standards ? automatic tri-level sync generation ? component (yp r p b ) or rgb hdtv outputs ? direct yp r p b or rgb output from progressive rgb graphics video in 1080i, 720p, 480p atsc resolutions software and register forward-compatib ility with the bt868/869 ability to accept many different input data formats: ? 15/16/24-bit rgb multiplexed or nonmultiplexed ? 16-bit 4:2:2 and 24-bit 4:4:4 ycrcb multiplexed or nonmultiplexed ? flexible pixel ordering with various alternate formats worldwide video output support: ntsc-m, j, 4.43, pal-b, d, g, h, i, m, n, nc, 60, and secam interlaced and noninterlaced outputs s-video output (simultaneous with composite ntsc, pal, or secam) scart rgb or y/ c output for europe ? 4th dac is composite video ? en50-049 and iec 933-1 compliant 5-line vertical filtering scaling for overscan compensation and flicker reduction adaptive flicker filtering for enhanced image and peaking filters for text sharpness (patents pending) ccir601/itu-rbt.601 (i.e., 480i) and ccir656 compatible input modes luma and chroma comb filtering 4 x 10-bit dacs programmable power management master, pseudo-master or slave timing operation auto detection of tv 44 autoconfiguration modes wide-screen signaling (wss) support for variable clock rates ? adheres to eiaj cpr-1024 and itu-r tst.1119-1 standards full register set readback capability 3.3 v operation with scalable low voltage graphic controller interface from 1.8 v to 1.1 v buffered crystal clock output pin component yuv analog output colorstream tm (eia 770.2) and super colorstream tm component video outputs macrovision 7.1.l1 copy protection (cx25871) compact 80-pin pqfp package
100381b conexant
100381b conexant ? 2001, conexant systems, inc. all rights reserved. information in this document is provided in connection with conexant systems, inc. (?conexant?) products. these materials are provided by conexant as a service to its customers and may be used for informational purposes only. conexant assumes no responsibility for errors or omissions in these materials. conexant may make c hanges to specifications and product descriptions at any time, without notice. conexant makes no commitment to update the information and shal l have no responsibility whatsoever fo r conflicts or incompatibilities aris ing from future changes to its spec ifications and product descriptions. no license, express or implied, by est oppel or otherwise, to any intellectual proper ty rights is granted by this document. exce pt as provided in conexant?s terms and conditions of sale for such products, conexant assumes no liability whatsoever. these materials are provided ?as is? without warranty of any kind, either express or implied, relating to sale and/or use of conexant products including liability or warranties relating to fitness for a particular purpose, consequential or incidental damages, merchantability, or infringement of any patent, copyright or other intellectual property right. conexant further does not warrant the accuracy or completeness of the information, text , graphics or other items contained within these materials. conexant shall not be liable for any special, indirect, incidental, or consequential damages, including without limitation, lost revenues or lost profits, which may result from the use of these materials. conexant products are not intended for use in medical, lifesavi ng or life sustaining applications . conexant customers using or selling conexant products for use in such applicat ions do so at their own risk and agree to fully indemnify conexant for any damages resulting from such improper use or sale. the following are trademarks of conexant systems, inc.: conex ant?, the conexant c symbol, and ?what?s next in communications technologies??. product names or services listed in this public ation are for identification purposes only, and may be trademark s of third parties. third-party brands and names ar e the property of thei r respective owners. for additional disclaimer information, please c onsult conexant?s legal information posted at www.conexant.com , which is incorporated by reference. reader response: conexant strives to produce quality documentation and welcomes your feedback. please send comments and suggestions to tech.pubs@conexant.com . for technical questions, contact your local conexant sales office or field applications engineer. ordering information model number package ambient temperature range CX25870 80-pin pqfp 0 c ? 70 c cx25871 (1) 80-pin pqfp 0 c ? 70 c note(s): 1. macrovision 7.1.l1 compliant (c ustomer must pos sess macrovision license to purchase cx25871).
100381b conexant
100381b conexant v table of contents list of figures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vii list of tables . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi 1.0 functional description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1 1.1 pin descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1 1.2 gui controller programmability and frequency requirement . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7 1.3 device description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10 1.3.1 overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10 1.3.2 serial interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-10 1.3.3 low voltage graphics interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11 1.3.4 reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-11 1.3.5 device initialization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-12 1.3.6 clocking and timing generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-13 1.3.6.1 3:2 clocking mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-14 1.3.7 master, pseudo-master, and slave interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-17 1.3.7.1 master interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-17 1.3.7.2 reason for blank* . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-18 1.3.7.3 pseudo-master interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-18 1.3.7.4 slave interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-19 1.3.7.5 slave interface without a crystal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-20 1.3.8 autoconfiguration and interface bits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-21 1.3.9 adaptations for clock-limited master devices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-25 1.3.10 input formats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-26 1.3.11 input pixel timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-27 1.3.12 ycrcb inputs (for standard tv outputs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-27 1.3.13 rgb inputs (for standard tv outputs) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-29 1.3.14 input pixel horizontal sync . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-29 1.3.15 input pixel vertical sync . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-30 1.3.16 input pixel blanking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-30 1.3.17 overscan compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-31 1.3.18 standard flicker filtering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-35 1.3.19 adaptive flicker filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-36 1.3.20 vga registers involved in the tv out process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-39 1.3.21 output modes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-40
CX25870/871 flicker-free video encoder with ultrascale technology vi conexant 100381b 1.3.22 analog horizontal sync . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-40 1.3.23 analog vertical sync . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-41 1.3.24 analog video blanking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-41 1.3.25 video output standards supported . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-41 1.3.26 subcarrier generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-51 1.3.27 subcarrier phase reset/offset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-51 1.3.28 burst generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-52 1.3.29 video amplitude scaling and sinx/x compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-52 1.3.30 chrominance disable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-52 1.3.31 field pin output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-53 1.3.32 buffered crystal clock output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-55 1.3.33 noninterlaced output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-55 1.3.34 closed captioning (cc) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-56 1.3.35 wide screen signaling (wss) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-57 1.3.36 chrominance and luminance processing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-58 1.3.37 color bar and blue field generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-61 1.3.38 ccir656 mode operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-63 1.3.39 ccir601 mode operation for dvd playback . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-65 1.3.39.1 ccir601 data in/ntsc out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-65 1.3.39.2 ccir601 data in/pal out . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-66 1.3.39.3 vga- compatible rgb data in/ntsc out . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-66 1.3.40 secam output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-68 1.3.41 macrovision copy protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-74 1.3.42 hdtv output mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-75 1.3.43 scart output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-75 1.3.44 interlaced standard definition analog component video tv outputs . . . . . . . . . . . . . . . 1-79 1.3.45 vga(rgb)?dac output operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-84 1.3.46 tv auto-detection procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-87 1.3.47 sleep/power management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-89 2.0 internal registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1 2.1 essential registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5 2.2 device address . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5 2.3 writing registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5 2.4 reading registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-6 3.0 pc board considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1 3.1 component placement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1 3.2 power and ground planes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2 3.3 recommended schematics and layout for CX25870/871 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-8 3.4 decoupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9 3.4.1 device decoupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9 3.4.2 power supply decoupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9 3.4.3 comp decoupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9
CX25870/871 flicker-free video encoder with ultrascale technology 100381b conexant vii 3.4.4 vref decoupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9 3.4.5 vbias decoupling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-9 3.5 signal interconnect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-10 3.5.1 digital signal interconnect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-10 3.5.2 analog signal interconnect . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-10 3.6 applications information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-11 3.6.1 changes required to accommodate CX25870/871 in bt868/869-designs . . . . . . . . . . . 3-11 3.6.1.1 software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-11 3.6.1.2 hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-12 3.6.2 programmable video adjustment controls . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-15 3.6.2.1 contrast . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-15 3.6.2.2 saturation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-16 3.6.2.3 brightness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-16 3.6.2.4 hue . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-17 3.6.2.5 sharpness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-17 3.6.2.6 dot crawl . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-17 3.6.2.7 standard and adaptive flicker filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-18 3.6.2.8 position . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-20 3.6.2.9 size . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-21 3.6.3 system block diagrams . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-26 3.6.4 electrostatic discharge and latchup considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-27 3.6.5 clock and subcarrier stability . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-28 3.6.6 filtering radio frequency modulator connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-29 3.7 cx870evk evaluation kit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-31 3.8 serial interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-33 3.8.1 data transfer on the serial interface bus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-33 4.0 parametric information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1 4.1 dc electrical parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1 4.2 ac electrical parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-4 4.3 mechanical drawing for 80-pin pqfp . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-17 appendix a. scaling and i/0 ti ming register calculations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . a-1 appendix b. approved crystal vendors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . b-1 appendix c. autoconfiguration m ode register values and details . . . . . . . . . . . . . . . . . . . . . . . . c-1 appendix d. closed caption pseudo code . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . d-1 appendix e. CX25870/871 hdtv output mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . e-1 e.1 introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . e-1 e.1.1 allowable interfaces for hdtv output mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . e-1 e.1.2 interface bit functionality in hdtv output mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . e-3
CX25870/871 flicker-free video encoder with ultrascale technology viii conexant 100381b e.1.3 interface timing between the hdtv source device (master ) and CX25870/ cx25871 (timing slave) e-3 e.1.4 automatic trilevel sync generation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . e-5 e.1.5 allowable resolutions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . e-7 e.1.6 720p support with characte r clock based data masters . . . . . . . . . . . . . . . . . . . . . . . . . e-8 e.1.7 automatic insertion of broad pulses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . e-9 e.1.8 hdtv output mode register and bit definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . e-9 e.1.9 color space conversion fu nctionality to support analog rgb or ypbpr component video outputs e-11 e.1.10 timing diagrams for hdtv output mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . e-11
CX25870/871 list of figures flicker-free video encoder with ultrascale technology 100381b conexant ix list of figures figure 1-1. pinout diagram for CX25870/871 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1 figure 1-2. flicker filter contro l diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-8 figure 1-3. CX25870/871 encoder core block diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-9 figure 1-4. allowable overscan compensation ratios for dual display, 800x600 input/ntsc output 1-15 figure 1-5. operating the CX25870/871 in master interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-17 figure 1-6. operating the CX25870/871 in pseudo-master interface . . . . . . . . . . . . . . . . . . . . . . . . . 1-18 figure 1-7. operating the CX25870/871 in slave interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-19 figure 1-8. decimation filter at fs=27 mhz. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-28 figure 1-9. windows desktop image from encoder without overscan compensation. . . . . . . . . . . . 1-33 figure 1-10. windows desktop image from CX25870 with overscan compensation . . . . . . . . . . . . . 1-34 figure 1-11. interlaced 525-line (n tsc) video timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-4 3 figure 1-12. interlaced 525-line (pal-m) video timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-44 figure 1-13. interlaced 625-line (pal-b, d, g, h, i, nc) video timing (fields 1 ?4) . . . . . . . . . . . . . . . 1-45 figure 1-14. interlaced 625-line (pal-b, d, g, h, i, nc) video timing (fields 5 ?8) . . . . . . . . . . . . . . . 1-46 figure 1-15. interlaced 625-line (pal-n) video timing (fields 1?4) . . . . . . . . . . . . . . . . . . . . . . . . . . 1-47 figure 1-16. interlaced 625-line (pal-n) video timing (fields 5?8) . . . . . . . . . . . . . . . . . . . . . . . . . . 1-48 figure 1-17. noninterlaced 262-line (ntsc) video timing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-49 figure 1-18. noninterlaced 262-line (pal-m) video timing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-49 figure 1-19. noninterlaced 312-line (pal-b, d, g, h, i, n, nc) video timing. . . . . . . . . . . . . . . . . . . . 1-49 figure 1-20. interlaced 625-line (secam-b, d, g, k, k1, l, m) video timing (fields 1-4) . . . . . . . . . . 1-50 figure 1-21. field pin output timing diagram (ntsc-m, j, 4.43 ). . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-53 figure 1-22. field pin output timing diagram (pal-b, d, g, h, i, nc) . . . . . . . . . . . . . . . . . . . . . . . . 1-54 figure 1-23. typical wss analog waveform (ntsc). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-57 figure 1-24. luminance upsampling filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-59 figure 1-25. text sharpness (lum inance upsampling) filter with peaking op tions . . . . . . . . . . . . . . . 1-59 figure 1-26. close-up of text sh arpness (luminance upsampling )filt er with peaking and reduction op- tions 1-59 figure 1-27. text sharpness (lumin ance peaking) filter options . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-60 figure 1-28. chrominance filter (chroma_bw = 0) - default . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-60 figure 1-29. chrominance wide bandwidth filter (chroma_bw = 1) . . . . . . . . . . . . . . . . . . . . . . . . . 1-60 figure 1-30. secam high frequency pre-emphasis filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-61 figure 1-31. composite and s-video format (internal colorbars). . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-62 figure 1-32. CX25870/871 connection to ccir656-compatible master device . . . . . . . . . . . . . . . . . . 1-63 figure 1-33. dvd playback utilizing gr aphics controller for color-space and progressive scan conversion 1-67 figure 1-34. CX25870 driving a type i scart connector (en 50-049 and iec 933-1 compliant) . . . . 1-78 figure 1-35. CX25870 driving a type ii scart connector (y/c and bbc scart compliant). . . . . . . . 1-79 figure 1-36. ypr pb component video signals using 100/0/100/0 color bars as the digital input signal (courtesy? eia-770.2-a standard, page 8 and eia-770.1 standard) 1-81
list of figures CX25870/871 flicker-free video encoder with ultrascale technology x conexant 100381b figure 1-37. filterless dac outputs for vg a (rgb)?dac output operation . . . . . . . . . . . . . . . . . . . . 1-86 figure 3-1. power plane illustration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-2 figure 3-2. connection diagram for output filters an d other key passive componen ts/standard definition tv out only 3-3 figure 3-3. connection diagram for output filters and other key passive components/standard and hdtv out 3-4 figure 3-4. CX25870/871 3.3 v recommended layout for connection with 3.3 v master de- vice standard definition tv out only 3-6 figure 3-5. CX25870/871 3.3 v/1.8 v recommended l ayout for connection with 1.8 v master de- vice standard definition tv out only 3-7 figure 3-6. conexant recommended gui for CX25870/871 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-15 figure 3-7. CX25870/871 autoconfiguration modes for 640x480 rgb in, ntsc out desktop resolutions 3-22 figure 3-8. CX25870/871 autoconfiguration modes for 40x480 rgb in, pal-bdghi out desktop resolu- tions 3-22 figure 3-9. CX25870/871 autoconfiguration modes for 800 x 600 rgb in, ntsc out desktop resolutions 3-23 figure 3-10. CX25870/871 autoconfiguration modes for 800 x 600 rgb in, pal-bdghi out desktop reso- lutions 3-23 figure 3-11. CX25870/871 autoconfiguration modes for 1024 x 768 rgb in, ntsc out desktop resolutions 3-24 figure 3-12. CX25870/871 autoconfiguration modes for 1024 x 768 rgb in, pal-bdghi out desktop res- olutions 3-24 figure 3-13. direction-less size control pad . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-25 figure 3-14. system block diagram for deskt op/portable pc with tv out . . . . . . . . . . . . . . . . . . . . . . 3-26 figure 3-15. system block diagram for graphi cs card with tv out . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-27 figure 3-16. sid/sic diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-34 figure 4-1. timing details for all interfaces . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-7 figure 4-2. master interface timing relationship/noninterl aced rgb/ycrcb input . . . . . . . . . . . . . . . 4-8 figure 4-3. pseudo-master interface timing relationshi p ? active line/noninterlaced rgb input . . . . 4-9 figure 4-4. pseudo-master timing rela tionship blank line/noninterlaced rgb/ycrcb input. . . . . . . 4-10 figure 4-5. slave interface timing relationship/noninterlaced rgb/ycrcb input . . . . . . . . . . . . . . . . 4-11 figure 4-6. slave interface timing relationship/inter laced nonmultiplexed rgb input (fld_mode = 10 ? default) 4-12 figure 4-7. slave interface timing relationship/interl aced nonmultiplexed ycrcb input (fld_mode = 01) 4-13 figure 4-8. slave interface timing relationship/interl aced nonmultiplexed ycrcb input (fld_mode = 00) 4-14 figure 4-9. hdtv output horizontal timing details: 1080i . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-15 figure 4-10. hdtv output horizontal timing details: 720p. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-16 figure 4-11. 80-pin pqfp package diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-17 figure a-1. allowable overscan compensation ratios for dual display, 640x480 input, ntsc output with 20 clock hblank period a-4 figure a-2. allowable overscan compensation ratios for dual display, 640x480 i nput, pal-bdghi output with 20 clock hblank period a-5 figure a-3. allowable overscan compensation ratios for dual display, 800x600 input, ntsc output . a-6 figure a-4. allowable overscan compensation ratios fo r dual display, 800x600 input, pal?bdghi output, standard clocking mode a-7
CX25870/871 list of figures flicker-free video encoder with ultrascale technology 100381b conexant xi figure a-5. allowable overscan compensat ion ratios for dual display, 800x 600 input, ntsc output in 3:2 clocking mode a-8 figure a-6. allowable overscan compensation ratios for dual display, 800x600 i nput, pal-bdghi output in 3:2 clocking mode a-9 figure a-7. allowable overscan compensation ratios fo r dual display, 1024x768 input, ntsc output . . . a-10 figure a-8. allowable overscan compensation ratios for dual display, 1024x768 input, pal-bdghi out- put a-11 figure e-1. CX25870/871?s pseudo-master interface with a graphics controller as the timing master e-2 figure e-2. CX25870/871?s slave interface with a graphics controller as the timing master . . . . . . . . e-2 figure e-3. typical trilevel sync provided by CX25870/871 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . e-7 figure e-4. proper interface timing between the hd tv source device (master) and CX25870/871 (timing slave): active line in 1080i and 720p atsc format (raster_sel[1:0] = 11 or 10), for r, g, b, and y analog outputs e-12 figure e-5. proper interface timing between the hd tv source device (master) and CX25870/871 (timing slave): active line in 1080i and 720p atsc format (raster_sel[1:0] = 11 or 10) for p 8 and p r analog outputs e-13 figure e-6. proper interface timing between the hd tv source device (master) and CX25870/871 (timing slave): broad pulse line in 1080i atsc form at (raster_sel[1:0] = 11) ? odd field e-14 figure e-7. proper interface timing between the hd tv source device (master) and CX25870/871 (timing slave): two successive active fields in 1080i atsc format (raster_sel[1:0] = 11) e-15 figure e-8. proper interface timing between the hd tv source device (master) and CX25870/871 (timing slave): broad pulse line in 720p atsc format (raster_s el[1:0] = 10) e-16
list of figures CX25870/871 flicker-free video encoder with ultrascale technology xii conexant 100381b
CX25870/871 list of tables flicker-free video encoder with ultrascale technology 100381b conexant xiii list of tables table 1-1. pin assignments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2 table 1-2. data pin assignments for multip lexed input formats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-5 table 1-3. data pin assignments for nonm ultiplexed input formats . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-6 table 1-4. maximum programmability and frequency requirements . . . . . . . . . . . . . . . . . . . . . . . . . . 1-7 table 1-5. autoconfiguration solutions that utilize 3:2 clocking mode . . . . . . . . . . . . . . . . . . . . . . . . 1-16 table 1-6. master interface without a blank* signal (default immediately afte r any autoconfiguration command) 1-21 table 1-7. master interface with a blank* input to the CX25870/871 . . . . . . . . . . . . . . . . . . . . . . . . 1-22 table 1-8. pseudo-master interface without a blank* signal. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-22 table 1-9. pseudo-master interface with a blank* input to the CX25870/871. . . . . . . . . . . . . . . . . . 1-23 table 1-10. slave interface without a blank* signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 -23 table 1-11. slave interface with a blank* input to the CX25870/871 . . . . . . . . . . . . . . . . . . . . . . . . . 1-24 table 1-12. adjustment to the CX25870/871 msc registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-25 table 1-13. adjustment to the pll_int and pll_fract register s . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-26 table 1-14. summary of allowable blank* signal directions by interface. . . . . . . . . . . . . . . . . . . . . . 1-31 table 1-15. optimal adaptive and standard flicker filter settings for common pc applications. . . . . . 1-38 table 1-16. vga/crtc registers involved in tv out process . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-39 table 1-17. important bit settings for various video outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-42 table 1-18. composite and luminance amplitude. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1- 62 table 1-19. composite and chrominance magnitude. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-63 table 1-20. register values for 640x480 / 800x600 / 1024x768 rgb in, secam-l out . . . . . . . . . . . . 1-69 table 1-21. vital secam bitsettings?register 0xa2 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 -72 table 1-22. secam specific registers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-74 table 1-23. serial writes required to switch CX25870/871 into scart output operation . . . . . . . . . . 1-76 table 1-24. default scart outgoing signal assignments . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-77 table 1-25. CX25870 scart outputs for different scart standards. . . . . . . . . . . . . . . . . . . . . . . . . . 1-78 table 1-26. common registers required to switch cx 25870/25871 into eia-770.2-a- or eia-770.1-compli- ant component video outputs 1-82 table 1-27. unique registers required to switch CX25870/25871 into eia-770.2-a- compliant component video outputs 1-82 table 1-28. serial writes required to switch CX25870/871 into vga/dac output operation . . . . . . . . 1-84 table 1-29. serial writes required to remove bilevel syn cs from all vga/dac outputs . . . . . . . . . . . 1-85 table 1-30. estatus[1:0] read-back bit map. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-88 table 2-1. register bit map (* indicates r ead-only register) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-1 table 2-2. serial address configuration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-5 table 2-3. bit map for read-only registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-7 table 2-4. data details defined for read-only registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2- 8 table 2-5. programming detail . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2-9 table 3-1. typical parts list for key passive components. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-5
list of tables CX25870/871 flicker-free video encoder with ultrascale technology xiv conexant 100381b table 3-2. relative register map for CX25870/871 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-1 1 table 3-3. hardware modifications to bt868/869-based pcb required to accommodate the CX25870/871 3-12 table 3-4. CX25870 optimal adaptive flicker filter bit settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3-19 table 4-1. recommended operating condition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1 table 4-2. absolute maximum rating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4-2 table 4-3. dc characteristics for CX25870/871. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3 table 4-4. ac characteristics for CX25870/871 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-4 table a-1. target video parameters for standard definition tv output formats . . . . . . . . . . . . . . . . . . a-2 table a-2. key parameters for supported standard definition video output formats . . . . . . . . . . . . . . a-3 table a-3. constant values dependent on encoding mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . a-3 table a-4. overscan values, 640 x 480 ntsc, pixel-based controller, 1-pixel resolu tion, 2.5 s hblank. . a-12 table a-5. overscan values, 640 x 480 ntsc, character clock-based controller, 8- pixel resolution, 2.5 s hblank a-14 table a-6. overscan values, 640 x 480 ntsc, character clock-based controller, 9- pixel resolution, 2.5 s hblank a-15 table a-7. overscan values, 640 x 480 pal-bdghi, pi xel-based controller, 1-pixel resolution, 2.5 s hblank a-16 table a-8. overscan values, 640 x 480 pal-bdghi, char acter clock-based controller, 8-pixel resolution, 2.5 s hblank a-19 table a-9. overscan values, 640 x 480 pal-bdghi, char acter clock-based controller, 9-pixel resolution, 2.5 s hblank a-20 table a-10. overscan values, 800 x 600 ntsc, pixel-based controller, 1-pixel resolution. . . . . . . . . . a-21 table a-11. overscan values, 800 x 600 ntsc, character clock-based controller, 8-pixel resolution, 0?1.5 s hblank a-25 table a-12. overscan values, 800 x 600 ntsc, character clock-based controller, 9-pixel resolution, 0?3.0 s hblank a-26 table a-13. overscan values 800 x 600 ntsc, pixel-based co ntroller, 1-pixel resolution, 3:2 clocking mode a-27 table a-14. overscan values 800 x 600 ntsc, character cl ocked-based controller, 8-pixel resolution, 3:2 clocking mode a-31 table a-15. overscan values 800 x 600 ntsc, character cl ocked-based controller, 9-pixel resolution, 3:2 clocking mode a-32 table a-16. overscan values, 800 x 600 pal-bdghi, pi xel-based controller, 1-pixel resolution, >2.5 s hblank a-34 table a-17. overscan values, 800 x 600 pal-bdghi, char acter clock-based controller, 8-pixel resolution a-36 table a-18. overscan values, 800 x 600 pal-bdghi, char acter clock-based controller, 9-pixel resolution a-37 table a-19. overscan values 800 x 600 pal-bdghi, pixel-based controller, 1-pixel resolution, 3:2 clocking mode a-38 table a-20. overscan values 800 x 600 pal-bdghi, charact er clock-based controller, 8-pixel resolution, 3:2 clocking mode a-41 table a-21. overscan values 800 x 600 pal-bdghi, charact er clock-based controller, 9-pixel resolution, 3:2 clocking mode a-41 table a-22. overscan values 1024 x 768 ntsc, pixel-based controller, 1-pixel resolution, >1.50 ms. hblank a-42 table a-23. overscan values 1024 x 768 ntsc, character clock-based controller, 8pixel resolution, >1.50
CX25870/871 list of tables flicker-free video encoder with ultrascale technology 100381b conexant xv s hblank a-46 table a-24. overscan values 1024 x 768 ntsc, character clock-based co ntroller, 9-pixel resolution a-47 table a-25. overscan values 1024 x 768 pal-bdghi, pixel-based controlle r, 1-pixel resolution, >3 ms. hblank a-49 table a-26. 1024 x 768 pal-bdghi, char acter clock-based controller, 8- pixel resolution , >4 ms. hblank a-52 table a-27. overscan values 1024 x 768 pal-bdghi, character clock-based controller, 9-pixel resolution a-52 table c-1. CX25870/871 register values for autoconfiguration modes 0?4 . . . . . . . . . . . . . . . . . . . . . c-1 table c-2. CX25870/871 register values for autoconfiguration modes 5?10 . . . . . . . . . . . . . . . . . . . . c-4 table c-3. CX25870/871 register values for autoconfiguration modes 11?15 . . . . . . . . . . . . . . . . . . . c-6 table c-4. CX25870/871 register values for autoconfiguration modes 16?21 . . . . . . . . . . . . . . . . . . . c-8 table c-5. CX25870/871 register values for autoconfiguration modes 22?26 . . . . . . . . . . . . . . . . . . c-10 table c-6. CX25870/871 register values for autoconfiguration modes 27?30 . . . . . . . . . . . . . . . . . . c-12 table c-7. CX25870/871 register values for autoconfiguration modes 31?36 . . . . . . . . . . . . . . . . . . c-14 table c-8. CX25870/871 register values for autoconfiguration modes 37?42 . . . . . . . . . . . . . . . . . . c-16 table c-9. CX25870/871 register values for autoconfiguration modes 43?47 . . . . . . . . . . . . . . . . . . c-18 table e-1. CX25870 register settings for 24-bit rgb multiplexed in, y/p r /p b hdtv out. . . . . . . . . . . e-4 table e-2. default state of CX25870/871 immediately after switch into hdtv output mode . . . . . . . . e-5 table e-3. CX25870/871 raster_sel[1:0] bit functionality. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . e-6 table e-4. CX25870/871 hdtv supported formats. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . e-7 table e-5. register bit map for hdtv-specific registers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . e -9 table e-6. CX25870/871 registers 0x2e & 0x32 ? hdtv output mode bit descriptions . . . . . . . . . . e-10
list of tables CX25870/871 flicker-free video encoder with ultrascale technology xvi conexant 100381b
100381b conexant 1-1 1 1.0 functional description 1.1 pin descriptions the pinout diagram is illustrated in figure 1-1 . pin names, input/output assignments, numbers, and descriptions are listed in tables 1-1 , 1-2 , and 1-3 . figure 1-1. pinout diagram for CX25870/871 reset* vdd vdd_vref sic p[0] p[1] p[2] p[3] p[4] p[5] p[6] p[7] sid blank* field vsync* hsync* vss p[23] p[22] p[21] p[20] p[19] p[18] sleep vdd vdd CX25870/871 80-pin pqfp agnd fsadjust vbias vref comp vaa_vref agnd_dac daca vaa_daca dacb vaa_dacb dacc vaa_dacc clki vdd_co clko vss_co vdd_so vaa_x xtalout xtalin vss_x p[8] p[9] p[10] p[11] p[12] p[13] p[14] p[15] p[16] p[17] pa l slave altaddr vss 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 vdd xtl_bfo vss vdd vss vss vdd vddl vss_si vss_so 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 61 60 59 58 57 56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 vaa_pll agnd_pll vdd_si agnd_dac vaa_dacd dacd vss/test 100381_002
1.0 functional description CX25870/871 1.1 pin descriptions flicker-free video encoder with ultrascale technology 1-2 conexant 100381b aside from pins 2, 3, 65, 66, and 67, which are no connects within the bt868/869, the CX25870/871 is comple tely pin-to-pin compatible with conexant?s first generation vga encoder. table 1-1. pin assignments (1 of 3) pin name i/o pin # description vaa_vref ? 80 analog power. all vaa and vdd pins must be connected together on the same pcb plane to prevent latchup. agnd ? 79 analog ground. all agnd and vss pi ns must be connected together on the same pcb plane to prevent latchup. fsadjust i 78 full-scale adjust c ontrol pin. a resistor (rset) connected between this pin and gnd controls the full-scale out put current on the analog outputs. vbias o 77 dac bias voltage. a 0.1 f ceramic capacitor must be us ed to bypass this pin to gnd. the capacitor must be as close to the device as possible to keep lead lengths to an absolute minimum. vref o 76 voltage reference pin. a 1.0 f ceramic capacitor must be used to decouple this pin to gnd. the decoupling ca pacitor must be as close to the device as possible to keep lead lengths to an absolute minimum. comp o 75 compensation pin. a 0.1 f ceramic capacitor must be used to bypass this pin to vaa. the capacitor must be as close to the device as possible to keep lead lengths to an absolute minimum. vaa_dacc ? 73 dacc analog power. all vaa and vdd pins must be connect ed together on the same pcb plane to prevent latchup. dacc o 72 dacc analog output. vaa_dacb ? 71 dacb analog power. all vaa and vdd pins must be connect ed together on the same pcb plane to prevent latchup. dacb o 70 dacb analog output. vaa_daca ? 69 daca analog power. all vaa and vdd pins must be connect ed together on the same pcb plane to prevent latchup. daca o 68 daca analog output. vaa_dacd ? 67 dacd analog power. all vaa and vd d pins must be connected together on the same pcb plane to prevent latchup. dacd o 66 dacd analog output. if unused, dacd should be le ft as a no connect. agnd_dac ? 65, 74 common dac analog ground retu rn. all agnd and v ss pins must be connected together on the same pcb plane to prevent latchup. vss_x ? 64 crystal oscillator ground pin. thi s pin should be tied to the ground plane. xtalin i 63 a crystal can be connected to thes e pins. the pixel cloc k output (clko) is derived from these pins with a pll. xtal in can be driven as a cmos input pin. internally, this is a cmos inverter ty ing xtalout to xtalin. if xtalout is unused, it should be left as a no connect. xtalout o 62 vdd_x ? 61 crystal oscillator supply pin. this pin should be tied to the power supply. vaa_pll ? 59 analog power for pll. all vaa and vd d pins must be connected together on the same pcb plane to prevent latchup. agnd_pll ? 58 analog ground for pll. all agnd an d vss pins must be connected together on the same pcb plane to prevent latchup.
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.1 pin descriptions 100381b conexant 1-3 vdd_co ? 57 clock output supply pin. this pin should be tied to the power supply. for low voltage infacing this pin should be tied to the low voltage supply. clko o 56 pixel clock output (ttl compatible). this pin is three-st ate if the clki pin provides the encoder clock. vss_co ? 55 clock output ground pin. this pin should be tied to the ground plane. clki i 54 pixel clock input (ttl compatible). this may be used as either the encoder clock or a delayed version of the clko pin synchronized with the pixel data input. reset* i 53 reset control input (ttl compatible ). a logical 0 applied for a minimum of 20 clki clock cycles resets and disabl es video timing (horizontal, vertical, subcarrier counters) to the start of vsync of the first field and resets the serial interface registers. reset* must be a logical 1(3.3 v) for normal operation. sleep i 52 power-down control input (ttl compat ible). a logical 1 c onfigures the device for power-down mode. a logi cal 0 configures the device for normal operation. slave i 51 slave/master mode se lect input (ttl compatible). a logical 1 configures the device for slave video timi ng operation. a logical 0 c onfigures the device for master video ti ming operation. pal i 50 pal/ntsc mode select input (ttl co mpatible). a logica l 1 configures the device for pal video format and auto configuration mode 1. a logical 0 configures the device for ntsc video format and autoconfiguration mode 0. vdd_vref i 49 input threshold adjustment. this pi n should be tied to vdd for 3.3 v input swings or vddl/2 for low voltage input swings. altaddr i 48 alternate slave addr ess input (ttl compatible). a logical 0 configures the device to respond to a serial write addr ess of 0x88. a logical 1 configures the device to respond to a serial write addres s of 0x8a. in additi on, serial reads to address 0x89 (altaddr = 0) or 0x8b (alt addr = 1) are possible with this pin. vdd_si ? 47 serial interface input supply pin. this pin should be tied to vdd (3.3 v). vdd_so ? 46 serial interface output supply pin. this pin should be ti ed to vdd (3.3 v). sic i 45 serial interface cl ock input (ttl compatible). sid i/o 44 serial interface data input/output (ttl compatible). data is written to and read from the device via this serial bus. vss_so ? 43 serial interface input ground pin. this pin should be tied to the ground plane. vss_si ? 42 serial interface input ground pin. this pin should be tied to the ground plane. vddl ? 40 digital power for low voltage interface. all vaa and vdd pins must be connected together on the same pcb plan e to prevent latchup. for a low voltage interface, this pin should be tied to the low voltage supply. vss/test i 39 test pin. should be ti ed to vss for normal operation. blank* i/o 38 composite blanking control (ttl compatible). thi s can be generated by the encoder or supplied from the graphics c ontroller. if internal blanking is used, this pin can be used to indicate the control charac ter clock edge . if unused, blank* should be tied high through a 10 k ? pullup resistor. table 1-1. pin assignments (2 of 3) pin name i/o pin # description
1.0 functional description CX25870/871 1.1 pin descriptions flicker-free video encoder with ultrascale technology 1-4 conexant 100381b field o 37 field control output (ttl compatible). field transiti ons after the rising edge of clk, two clock cycles following falli ng hsync*. it is a logical 0 during odd fields and is a logical 1 dur ing even fields. if unused, field should be left as a no connect. vsync* i/o 36 vertical sync input /output (ttl compatible). as an output (timing master operation), vsync* is output following th e rising edge of clk. as an input (timing slave operation), vsync* is clocked on th e rising edge of clk. hsync* i/o 35 horizontal sync i nput/output (ttl compatible). as an output (timing master operation), hsync* is output following th e rising edge of clk. as an input (timing slave operation), hsync* is clocked on the rising edge of clk. p[23:21] i 34-32 pixel inputs. see table 1-2 . the input data is sampled on both the rising and falling edge of clk for multiplexed mo des, and on the rising edge of clk in nonmultiplexed modes. a higher bit index corresponds to a greater bit significance. p[20:14] i 29-23 p[13:0] i 18-5 vss ? 4, 21, 22, 31, 41 digital ground for core logic. all ag nd and vss pins mu st be connected together on the same pcb plane to prevent latchup. xtl_bfo o 3 buffered crystal clock output. on power -up, the encoder will transmit a 0 to 3.3 v signal at a frequency equal to the fre quency of the crystal found between the xtalin/xtalout ports. normally the xtl_b fo output is at a rate of 13.500 mhz. if unused, xtl_bfo should be left as a no connect. vdd ? 1, 2, 19, 20, 30, 60 digital power for core logic. all vaa a nd vdd pins must be connected together on the same pcb plane to prevent latchup. table 1-1. pin assignments (3 of 3) pin name i/o pin # description
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.1 pin descriptions 100381b conexant 1-5 table 1-2. data pin assignments for multiplexed input formats falling edge of clki in_mode[3:0] 0000 0010/0001 0101 0100 1000 0110 1100 pin 24-bit rgb mode 15/16-bit rgb mode 16-bit ycrcb mode 24-bit ycrcb mode alternate 24-bit rgb mode alternate 16-bit ycrcb mode alternate 24-bit ycrcb mode p[11] r7 r4 y7 y7 r7 ? cr7 p[10] r6 r3 y6 y6 r6 ? cr6 p[9] r5 r2 y5 y5 r5 ? cr5 p[8] r4 r1 y4 y4 r4 ? cr4 p[7] r3 r0 y3 y3 r3 y7 cr3 p[6] g7 g5 (1) y2 y2 r2 y6 cr2 p[5] g6 g4 y1 y1 r1 y5 cr1 p[4] g5 g3 y0 y0 r0 y4 cr0 p[3] r2 ? ? cb3 g7 y3 y7 p[2] r1 ? ? cb2 g6 y2 y6 p[1] r0 ? ? cb1 g5 y1 y5 p[0] g1 ? ? cb0 g4 y0 y4 rising edge of clki p[11] g4 g2 cr/cb7 cr7 g3 ? y3 p[10] g3 g1 cr/cb6 cr6 g2 ? y2 p[9] g2 g0 cr/cb5 cr5 g1 ? y1 p[8] b7 b4 cr/cb4 cr4 g0 ? y0 p[7] b6 b3 cr/cb3 cr3 b7 cr/cb7 cb7 p[6] b5 b2 cr/cb2 cr2 b6 cr/cb6 cb6 p[5] b4 b1 cr/cb1 cr1 b5 cr/cb5 cb5 p[4] b3 b0 cr/cb0 cr0 b4 cr/cb4 cb4 p[3] g0 ? ? cb7 b3 cr/cb3 cb3 p[2] b2 ? ? cb6 b2 cr/cb2 cb2 p[1] b1 ? ? cb5 b1 cr/cb1 cb1 p[0] b0 ? ? cb4 b0 cr/cb0 cb0 note(s): (1) g5 is ignored in 15-bit rgb multiplexed input mode.
1.0 functional description CX25870/871 1.1 pin descriptions flicker-free video encoder with ultrascale technology 1-6 conexant 100381b table 1-3. data pin assignments for nonmultiplexed input formats in_mode[3:0] 1010 1110 0011 0111 1011 1111 pin 16-bit nonmux rgb 16-bit nonmux ycrcb 24-bit nonmux rgb 24-bit nonmux ycrcb alternate 16-bit nonmux rgb alternate 24-bit nonmux ycrcb p[23] ? ? b7 cb7 r7 cr7 p[22] ? ? b6 cb6 r6 cr6 p[21] ? ? b5 cb5 r5 cr5 p[20] ? ? b4 cb4 r4 cr4 p[19] r4 y7 b3 cb2 r3 cr3 p[18] r3 y6 b2 cb2 r2 cr2 p[17] r2 y5 b1 cb1 r1 cr1 p[16] r1 y4 b0 cb0 r0 cr0 p[15]r0y3g7cr7g7y7 p[14]g5y2g6cr6g6y6 p[13]g4y1g5cr5g5y5 p[12]g3y0g4cr4g4y4 p[11] g2cr/cb7g3 cr3 g3 y3 p[10] g1cr/cb6g2 cr2 g2 y2 p[9] g0 cr/cb5 g1 cr1 g1 y1 p[8] b4 cr/cb4 g0 cr0 g0 y0 p[7] b3 cr/cb3 r7 y7 b7 cb7 p[6] b2 cr/cb2 r6 y6 b6 cb6 p[5] b1 cr/cb1 r5 y5 b5 cb5 p[4] b0 cr/cb0 r4 y4 b4 cb4 p[3] ? ? r3 y3 b3 cb3 p[2] ? ? r2 y2 b2 cb2 p[1] ? ? r1 y1 b1 cb1 p[0] ? ? r0 y0 b0 cb0
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.2 gui controller programmab ility and frequency requirement 100381b conexant 1-7 1.2 gui controller programmability and frequency requirement programmability and frequency requirements for the graphics controller/data master device are defined in table 1-4 for the most commo n input resolutions. table 1-4 contains maximum values for the dual display solutions that provide 8 percent to 32 percent horizontal and ve rtical overscan compensation. for larger overscan compensation percentages, th e values would be larger. the maximum pixel frequency supported is 53.333 mhz for standard clocking mode and 80.000 mhz for 3:2 clocking mode. table 1-4. maximum programmability and frequency requirements desktop input mode maximum total maximum end of active to vsync maximum frequencies pixels/htotal lines/vtotal lines line (khz) pixel (mhz) 640 x 480 1075 665 76 39.860 31.563 800 x 600 1075 835 91 49.450 39.997 800 x 600 (3:2 clk mode) 1625 834 92 49.630 59.063 1024 x 768 (3:2 clk mode) 1625 1068 122 63.776 75.750
1.0 functional description CX25870/871 1.2 gui controller program mability and frequency requirement flicker-free video encoder with ultrascale technology 1-8 conexant 100381b figure 1-2. flicker filter control diagram input in_mode[3:0] 0000 = 24-bit rgb mux adpt_ff = 0; f_sely[2:0] 000 = 5 line 001 = 2 line 011 = 4 line 100 = alt. 5 line 1 adpt_ff = 0; f_selc[2:0] 000 = 5 line 001 = 2 line 100 = alt. 5 line 1 111 = alt. 5 line 4 dis_gmshy ylpf[1:0] 00 = bypass 01 = luma, horizontal lpf1 yattenuate[2:0] 000 = 1.0 gain 001 = 15/16 gain 010 = 7/8 gain 011 = 3/4 gain 100 = 1/2 gain cattenuate[2:0] 000 = 1.0 gain 001 = 15/16 gain 010 = 7/8 gain 011 = 3/4 gain flicker filter/scaler 0 = enable luma psuedo gamma removal 0001 = 16-bit rgb mux 1010 = 16-bit rgb non-mux 0010 = 15-bit rgb mux 0011 = 24-bit rgb non-mux 0101 = 16-bit ycrcb mux 0110 = alternate 16-bit ycrcb mux 10 = luma, horizontal lpf2 11 = luma, horizontal lpf3 clpf[1:0] 00 = bypass 01 = reserved 10 = chroma, horizontal lpf2 11 = chroma, horizontal lpf3 ycoring[2:0] 001 = 1/128 of range 010 = 1/64 of range 011 = 1/32 of range 100 = 1/16 of range 101 = 1/8 of range 110 = 1/4 of range 111 = reserved dis_gmshc 0 = enable chroma psuedo gamma removal dis_gmushy 0 = enable luma anti-pseudo gamma removal dis_gmushc 0 = enable chroma anti-psuedo gamma removal dis_yflpf 0 = enable initial luma horizontal low pass filter ccoring[2:0] 001 = +/-1/256 of range 010 = +/- 1/128 of range 011 = +/- 1/64 of range 100 = +/- 1/32 of range 101 = +/- 1/16 of range 110 = +/- 1/8 of range 111 = reserved 000 = bypass 000 = bypass 0111 = 24-bit ycrcb non-mux 1110 = 16-bit ycrcb non-mux 0100 = 24-bit ycrcb mux 1000 = alternate 24-bit rgb mux 1100 = alternate 24-bit ycrcb mux 1001 = reserved 1101 = reserved 1011 = alternate 24-bit rgb non-mux 1111 = alternate 24-bit rgb non-mux color space converter 100381_003 fifo 111 = alt. 5 line 4 110 = alt. 5 line 3 101 = alt. 5 line 2 011 = 4 line 010 = 3 line 110 = alt. 5 line 3 101 = alt. 5 line 2 adpt_ff = 1; y_atlff[1:0] 00 = 5 line 01 = 2 line 11 = 4 line 10 = 3 line adpt_ff = 1; c_atlff[1:0] 00 = 5 line 01 = 2 line 11 = 4 line 10 = 3 line 111 = 0.0 gain 110 = 1/8 gain 101 = 1/4 gain 111 = 0.0 gain 110 = 1/8 gain 101 = 1/4 gain 100 = 1/2 gain 010 = 3 line
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.2 gui controller programmab ility and frequency requirement 100381b conexant 1-9 figure 1-3. CX25870/871 encoder core block diagram 100381_004 internal voltage reference fsadjust daca video timing control, sid registers sic sid reset* 10 comp dacb 10 dacc dacd 10 10 out mux out mode 24 rgb/ ycrcb/ yprpb y[9:0] crcb[9:0] dac dac dac dac vbias + sync processor + 1.3 mhz lpf and 2x upsample/ matrix multiplication modulator, mixer and secam filt. hdtv sync gen. 10 color space convert closed captioning, macrovision vref luma delay 9 luminance 2x upsample and cross color peaking filt. cgms + y cvbs u/v rgb cvbs c dly sync_amp my burst processor bst_amp hue_off mcr hsync* vsync* mcb x x
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-10 conexant 100381b 1.3 device description 1.3.1 overview the CX25870/871 is a video encoder designed for tv output of interlaced and noninterlaced graphics data. common appli cations requiring flicker-filtered tv output include: desktop/portable pcs with tv out high definition tvs dvd players and set top boxes graphic cards with tv out game consoles set-top boxes it incorporates normal and adaptive filtering technology for flicker removal and flexible amounts of overscan compensation for high-quality display of noninterlaced images on an interlaced tv. the CX25870/871 accomplishes this by minimizing the flicker and controllin g the amount of overscan so that the entire image is viewable. the CX25870/871 consists of a color sp ace converter/flicker filter engine followed by a digital video encoder. the color space converter/flicker filter contains: a timing converter various horizontal video processing functions flicker filter and vertical sc aler for overscan compensation the output of this engine feeds into a fifo for synchronization with the digital video encoder. the CX25870/871 provides composite, s-video, or 3-signal analog rgb or yp b p r hdtv output. while the encoder is in hdtv output mode, the device will automatically insert trilevel synchronization pulses (when necessary) and vertical synchronizing ?broad pulses.? the CX25870/871 is compliant with eia770-3, smpte 274m/293m/296m and supports atsc hdtv resolutions including 480p, 720p, and 1080i. 1.3.2 serial interface the device includes a 2-wire read and wr ite serial interface for programming the registers in the device. the interface is designed to operate with 3.3 v levels. to ensure that valid serial data is receive d and transmitted, make sure the vdd_si pin is connected to a stable 3.3 v supply. review chapter 2.2 , chapter 2.3 and chapter 2.4 for more details of the encoder?s serial interface.
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-11 1.3.3 low voltage graphics interface the CX25870/871 can receive or transmit si gnals from/to a graphics controller at any of five different voltage levels. the allowable voltage levels are 3.3 v, 1.8 v, 1.5 v, 1.3 v, and 1.1 v. default input/o utput voltage amplitude for the interface signals (defined as p[23:0], hsyn c*, vsync*, clki, clko, blank*, and field) is 3.3 v and matches the bt868/869 to ensure backwards compatibility. for a 3.3 v digital interface, no speci al configuration steps are necessary. simply follow ?recommended layout for connection with a 3.3 v master device? in chapter 3.3 and on power-up, the encoder will automatically expect 3.3 v signal transitions. for a 1.8 v or lower digital interface, several special configuration steps are necessary. first, the layout must adhere to chapter 3.3 ?s ?3.3 v/1.8 v. recommended layout for connection with a 1.8 v master device.? second, program the drvs[1:0] field (bits[6:5] of register (0x3 2)) to 01(or an alternate value for 1.5 v, 1.3 v or 1.1 v interface). this forces the encoder to increase its drive strength on each interface signal used as an output in the interface. third, connect the vddl (pin 40) and vdd_co (pin 57) power supply pins to the correct lower supply voltage (1.8 v or other). fourth, using a voltage divider circuit or some other method, tie the CX25870/871?s vdd_vref input (pin 49) to a level equal to (vddl/ 2 ). make sure this voltage source is stable since the vddl pin controls the output signal levels. the vdd_vref pin dictates the encoder threshold voltage rece ived for the appropriate in put signals. the third and fourth steps are illustrated in figure 3-5 . make sure the graphics controller is configured to send an d accept signals at the lower supply voltage. adjusting vdd_co, vddl and vdd_vr ef appropriately controls the input voltage levels for the digita l input pins p[23:0], clki, and hsync*/vsync*/blank* (in slave interface; en_blanko = 0). using the drvs[1:0] bits control the ou tput voltage levels for the digital output pins clko, field, and hsync*/vsync*/blank* (in ma ster or pseudo-master interface; en_blanko = 1). in this way, the digita l input pins can operate at different input voltage levels than the digital output voltage levels.
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-12 conexant 100381b table 1-5. digital pins that comprise the low voltage graphics interface pin # pin name direction of pin 5 pixel[0] input 6 pixel[1] input 7 pixel[2] input 8 pixel[3] input 9 pixel[4] input 10 pixel[5] input 11 pixel[6] input 12 pixel[7] input 13 pixel[8] input 14 pixel[9] input 15 pixel[10] input 16 pixel[11] input 17 pixel[12] input 18 pixel[13] input 23 pixel[14] input 24 pixel[15] input 25 pixel[16] input 26 pixel[17] input 27 pixel[18] input 28 pixel[19] input 29 pixel[20] input 32 pixel[21] input 33 pixel[22] input 34 pixel[23] input 35 hsync* input or output 36 vsync* input or output 37 field output 38 blank* input or output 54 clki input 56 clko output
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-13 1.3.4 reset if the reset* pin is held low (between 0.8 v and gnd ?0.5 v) for a minimum of 20 clock cycles, a timing reset and a software reset is performed and the serial interface is held in the re set condition. a timing reset, which can be generated by setting the timing_rst register bit, will set the subcarrier phase to zero, and configure the horizontal and vertical co unters to the beginning of vsync* of field 1 (both counters equal to zero). if the CX25870/871 is in the master in terface (i.e., CX25870 sends the syncs to the data master) then after a power-on or pin reset the encoder and the flicker filter starts a line 1, pixel 1 of their re spective timing generation. for the encoder this means the odd field is always the firs t field after a power-on reset, pin reset, or timing reset. in timing the slave interface (CX25870 is either pseudo-master or pure slave), even though the input is receiving progressive frames that have no field associated with it, the input timing gene rator keeps track of the frames received. as a result, after every second frame receive d, a frame sync is sent to the encoder section so that the input and encoder rema in synchronized. the frame sync forces the encoder to the beginning of the odd field. conexant recommends that after every ov erscan compensation or video output type change, the timing_rst bit be enab led. the setting of the timing_rst bit should occur after waiting a minimu m of 1 ms between the last CX25870 register write for the new overscan compensation ratio. the timing_rst register bit clears itself and reinitial izes the internal timing generators. a software reset, which can be generated by setting the sreset register bit, initializes all the serial interface registers to their default state. as a result, all digital output control pins are three-stated. registers 0x38 and 0x76 to 0xb4 inclusive are then initialized to auto -configuration mode 0 (see the auto configuration section values) or mode 1 depending on the state of the pal pin. the en_out bit must be set to enable the digital outputs. a power-on reset, pin reset, or timing reset (register 0x6c, bit 7) causes the input timing generator to send the encode r a frame synchronization pulse setting the encoder to the beginning of the odd field. the first hsync*/vsync* combination then corresponds to the en coder even field and then the second hsync*/vsync* combination again causes a frame synchronization pulse and the encoder will start the odd field, and so on and so forth. a power-on reset is generated on power-up. the power-on reset generates the same type of reset as the reset* pin. a time delay circuit triggered after the supply voltage reaches a value sufficiently high enough for the circuit to operate and then generate the power-on reset. as such, the device may not initialize to the default state unless the power supply ramp rate is sufficiently fast enough. a hardware/pin reset is recommended if the default state is required. 1.3.5 device initialization after a reset condition, the device must be programmed through the serial interface to activate a video output and enable the clko, hsync*, vsync*, and field outputs. the easiest method fo r accomplishing the initialization phase is to use one of the auto configuration modes in appendix c , and program the interface bits appropriately. (refer to section 1.3.8 .)
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-14 conexant 100381b 1.3.6 clocking a nd timing generation two timing generators control the operation of the encoder. the output encoder timing block generates the signals for th e proper encoding of the video into ntsc, pal, or secam and extracts the pro cessed input pixels from the internal fifo. the encoding timing generator can receive its clock from either an external crystal oscillator and internal pll (mas ter and pseudo-master interface), or from the clki pin (slave interface). conexant recommends that the encoding clock be generated by the pll. register bit ex_xclk selects the clock source. if en_xclk is set to a logical 0, the internal clock source is selected via the crystal attached to xtalin/xtalout. when the en_xclk bit is set, the clock source received at the clki pin is utilized as the main pixel/encoder clock. conexant recommends that the encoding clock be generated by the pll. a crystal must be present between xtalin and xtalout pins if the internal clock source is selected. in th is case, the CX25870/871?s clk frequency is synthesized by its pll such that the pixel clock frequency equals for pll div10=0: f clk = f xtal * {pll_int(5:0) + [pll_fract(15:0)/2 16 ]}/6 for pll div10=1: f clk = f xtal * {pll int(5:0) + [pll fract(15:0)/2 16 ]}/10 where: f clk = clko output frequency = clki input frequency note: in some special modes, clko = f clk / 2. the crystal must be chosen so that the precise line rate for the video standards required can be achieved. this is done to maintain the subcarrier relationship to the line rate and thereby achieve the prec ise subcarrier frequ ency required. the crystal oscillator is designed to oscillate from 5 mhz through 25 mhz. a 13.5000 mhz crystal meets the requirem ents for ntsc, pal, and secam video standards. the crystal must be within 50 ppm of the maximum desired clock rate for ntsc operation, and 25 ppm for pal or secam operation, across the temperature range (0 to 70 c). if the CX25870/871 is to provide all video outputs selectable through software, the customer must use a crystal with a maximum tolerance across the te mperature range of 25 ppm. appendix b contains a list of previously test ed and recommended crystal vendors. the crystal oscillator is disabled by the xtal _pad_dis register bit. sufficient time (20 s) must be allowed after coming out of sleep mode to allow the oscillator to stabilize. the pll_lock bit is set when the pll is stable. in addition, if the pll_input register bit is set to a logical 1, clki is selected as the reference for pll. in this special mo de (slave interface with the pll_32clk high), the above f clk formulas replace f xtal with fclki/2 (i.e., input clock frequency is divided by 2). if the external clock source is selected (en_xclk=1), a clock signal of the desired pixel clock rate must be presen t at the clki pin. the clko pin is three-stated, and the crystal oscillator disabled. the clock must meet the same requirements as above. it is highly recomm ended that the internal clock be used in order to ensure the output video remains within the specificat ions defined by the relevant video standard. any aberration in the source clock is reflected in the color subcarrier frequency of the output video and detracts from the quality of the image on the television.
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-15 the by_pll bit bypasses the pll, and the encoder clock will be at the crystal frequency. this bit takes precedence over the en_xclk bit. the second timing generator controls the generation of the hsync*, vsync*, and blank* signals, and pixel input clocking. this is normally the same clock as the encoding clock. the en_a sync register bit, if set, allows this clock to be driven directly by the clki pin. if the div2 register bit is set, this internal clock is divided by two before driving the second timing generator. this is required for interlaced input to interlaced output mode (i.e., ccir601/dvd and ccir656 applications). the clki pin is the clock used for synchronizing pixel inputs (p[23:0]) with the timing input signals (hsync*, vsyn c*, and blank*) and normally is a delayed version of the clko pin. it can be directly connected to clko if desired. data is registered with this input and re-synchroni zed to the internal clock. in a multiplexed input mode, both edges of the clki input are used. if the mode2x register bit is set, the internal clock is divided by two, allowing a 2x external clock, and data to be provided on the rising edge only. 1.3.6.1 3:2 clocking mode all graphics controllers re quire some finite time for resetting their internal counters to zero, clearing re gister flags, and any other event that needs to be performed on a line-by-line basis. the sum of time th ese incidents take are the graphics controller?s horizontal blan king time. the amount of horizontal blanking time varies from one master device to another but it can never be less than 0 s and usually does not exceed 4 s per digital line.
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-16 conexant 100381b figure 1-4 illustrates higher resolutions (i.e., 800x600 or greater), for some data master devices that require more horizontal blanking time than the CX25870/871 provides in standard clocking mode, for dual display of certain overscan compensation percentage pairs. for example, a graphics controller may require a minimum total of 1.25 s of ho rizontal blanking ti me per line while clocking a frame with an active resolution of 800x600 to the encoder. if this were the case, the entire set of overscan co mpensation solutions charted at the 1 s diagonal plot line (denoted with a dot-dash-dot) and below are made unavailable to the designer. the result is a more limite d set of overscan pairs to choose from, and correspondingly less size control for the picture when displayed on a television. figure 1-4. allowable overscan compensation ratios for dual display, 800x600 input/ntsc output note(s): use this chart for pal m and pal 60 allowable overscan ratios 8 10 12 14 16 18 20 22 8 10 12 14 16 18 20 22 24 vertical overscan compensation percentage horizontal overscan compensation percentage overscan compensation percentage pairs for 800x600 ntsc 0 s horizontal blanking 1 s 2 s 3 s .75 s = pixel clock solution = 8-cycle character clock solution = 9-cycle character clock solution legend:
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-17 since the CX25870/871 contains this new 3:2 clocking mode, the designer does not face this constraint any lo nger. by choosing an appropriate autoconfiguration mode, setti ng the pll_32clk bit to 1, and altering the values for various timing registers within the controller and encoder (e.g., h_clki = htotal, vlines_i = vtotal , h_blanki, v_blanki, etc.), the encoder switches into the 3:2 clock mode. while in this operational state, additional solution s in the overscan-compensatio n-pairs domain for higher resolutions now exist. in addition, the encoder now allows the data master (e.g., graphics controller) to send di gital data to it at a faster rate than is clocked out of the encoder. specifically, the CX25870/871 be gins to transfer pixels out at a rate of [2/3] that of the clki input freque ncy. in other words, the pixel input frequency clocks in data at a ratio of [3:2] or 1? times faster than the CX25870/871 outputs the analog pixel data. in this mode, the encoder's expansive on-chip fifo bridges the frequency diff erence that now exists between the digital-timing input and mixed-signal encoder output blocks of the CX25870/871. the result is a much closer match in the available overscan percentages in the horizontal and vertical direction for the higher resolutions. this ensures the tv out picture appears more orthogonal wher e the amount of bl anking is nearly equal on all sides of the image. since the horizontal blanking time on ly becomes a critical issue at higher resolutions, the user should use a 3:2 clocking mode only when necessary at 800x600, and always at 1024x768. for software programming ease, some of the autoconfiguration modes for 800x600 and all for the 1024x768 resolution are 3:2 solutions already. the specific modes that use the 3:2 clock feature are contained in appendix c and summarized in table 1-6 below. table 1-6. autoconfiguration solutions that utilize 3:2 clocking mode autoconfiguration mode # active resolution type of digital input overscan ratio video output type 10 1024x768 rgb standard ntsc 11 1024x768 rgb standard pal-bdghi 14 1024x768 ycrcb standard ntsc 15 1024x768 ycrcb standard pal-bdghi 18 800x600 rgb lower ntsc 22 800x600 ycrcb lower ntsc 26 1024x768 rgb lower ntsc 30 1024x768 ycrcb lower ntsc 34 800x600 rgb higher ntsc 40 800x600 rgb alternate ntsc 42 1024x768 rgb higher ntsc 43 1024x768 rgb higher pal-bdghi
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-18 conexant 100381b if the desired overscan ratio is not ava ilable via a particular autoconfiguration mode, you should derive another 3:2 solution via super cockpit (i.e., CX25870 register programming tool), or contact your local fae directly. if done correctly, this CX25870/871 register set will have pll_32clk (bit 5 of register 0x38) set and adjust the timing registers appropriately. 1.3.7 master, pseudo-mas ter, and slave interfaces like its predecessor, the bt868/869, the CX25870/871 encoder can be operated in three possible interfaces. these connection types are named master, pseudo-master, and slave. the clocking ab ility of the master device and direction of the timing signals dictate what part icular interface is used between the conexant encoder and graphics controller/data master device. 1.3.7.1 master interface in master interface, clko, hsync*, vsync*, and blank*, are generated by the encoder as outputs. these signals? leading edges denote when a new clock period, new line, and new frame starts respectively. because the encoder transmits the clock and timing signals, this interf ace is also referred to as clocking master/timing master. an illustration of the master interfa ce is shown below using the graphics controller as the master device and s-vi deo and two composite ports as the video outputs. a minimum of 9 inputs (clki and 8 lines for pixel data- p[7:0]) and 3 outputs (hsync*, vsync*, and clko) are requ ired for this configuration. the amount of inputs could grow as high as 25 if 24-bit rgb nonmultiplexed mode is chosen as the input pixel mode (i.e., in_mode[3:0] = 0011) by the designer. master interface can only exist if th e graphics controll er can accept the encoder?s reference clock and send back a version of that clock at the same frequency with the pixel data transitions synchronized to clki?s rising and falling edges. this is accomplished vi a the vga encoder?s clock output (clko) and clock input (clki) ports. figure 1-5. operating the CX25870/871 in master interface graphics controller rgb or ycrcb clock clko clki clock CX25870/ cx25871 composite #1 composite #2 s-video luma chroma delay hsync* vsync* blank* 100381_054
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-19 1.3.7.2 reason for blank* if the graphics controller possesses pixel-ba sed resolution (i.e., pixels are only a single pixel clock wide) then the encoder does not have to tr ansmit or receive the blank* signal. however, for graphics cont rollers that are character clock based, a blank* signal is necessary. the blank line is necessary because a character clock is actually 8 or 9 pixel clocks in duration. this causes severa l pixel clocks to elapse, resulting in an erroneous delay prior to the next hsync* being observed by the encoder and the next line starting. the only method of compensating for this delay is for character clock based controllers to use the blank* signal. this signal is required in the physical interface to indicate the exact lo cation of the first active pixel on each line. 1.3.7.3 pseudo-master interface in pseudo-master interface, the CX25870/ 871 generates clock reference signal, clko as an output. this signal?s purpose is to inform the graphics controller the exact frequency at which the data must be sent to the encoder. timing signals, hsync*, vsync*, and blank*, are received by the encoder as inputs. the leading edges of these signals denote when a new clock period, new line, and new frame starts, respectively. because this connection scheme shares mastering responsibilities, the interface is also named clocking master/timing slave. an illustration of the pseu do-master interface is illustrated below using the graphics controller as th e timing master device. a minimum of 11 inputs (clki, hs ync*, vsync*, and 8 lines for pixel data- p[7:0]) and 1 output (clko) are required for this configuration. the amount of inputs could grow as high as 28 if 24-bit rgb nonmultiplexed mode is chosen as the input pixel mode (i.e., in_mode[3:0] = 0111) by the designer. pseudo-master interface can only exist if the graphics controller can accept the encoder?s reference clock and send back a version of that clock at the same frequency with the pixel data transitions synchronized to clki?s rising and falling edges. this is accomplished vi a the vga encoder?s clock output (clko) and clock input (clki) ports. figure 1-6. operating the CX25870/871 in pseudo-master interface graphics controller rgb or ycrcb clock clko clki clock CX25870/ cx25871 composite #1 composite #2 luma chroma delay hsync* vsync* blank* 100381_055
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-20 conexant 100381b 1.3.7.4 slave interface in slave interface, no output signal s are generated by the encoder. the CX25870/871 relies strictly on the graphi cs controller to send clock and timing signals to trigger when a new clock period, new line, and new frame starts. because no frequency reference signal is used (clko), the master device must pre-program the encoder with an appropriate register set so the CX25870/871 expects data at the specific digital pixel rate prior to actually receiving the data. in addition, the timing signals mu st be shaped so they adhere to the appropriate slave interface timing diagrams illustrated in chapter 4.0 . due to the added complexity of this interface, conexant recomme nds its use only as a final option. the slave interface is illustrated in figure 1-7 below using the graphics controller as the master device and s-video and 2 composite ports as the video outputs. a minimum of 11 inputs (clki, hsync*, vsync*, and p[7:0]) are required for this configuration. the amount of inputs will increase to 15 (without blank*) or 16 (with blank*) if 24-bit multiplexed rgb mode is chosen as the input pixel mode (i.e., in_mode[3:0] = 0000) by the designer. it is highly recommended that the devi ce operate in master or pseudo-master interface to ensure that th e input and output video streams remain synchronized. if either the master device, supplying the hsync* and vsync* inputs, or the encoder, which receives the data, is no t correctly programmed, the output image will lose lock with the input. by running the CX25870/871 in either clock master interface, any timing errors that occur can be absorbed to some extent by the expansive on-board fifo. figure 1-7. operating the CX25870/871 in slave interface graphics controller rgb or ycrcb clki clock CX25870/ cx25871 composite #1 composite #2 luma chroma hsync* vsync* blank* 100381_056
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-21 1.3.7.5 slave interface without a crystal for price-sensitive applications, it is po ssible to remove the crystal found between the xtalin and xtalout ports and strict ly utilize the incoming clki signal as both the data transfer mechanism and internal ma in clock source for the encoder. to complete this architecture, the data mast er must also program the CX25870?s en_xclk bit to 1. this will trigger clki to be used for all operations requiring a clock source an d force the encoder to ignore any oscillations received via its xtalin and xtalout pins. the flicker filter and timing blocks will utilize this asynchro nous clock on the input side for data processing, and the encoder will comb ine its internal pll and clki in conjunction with the dacs to transmit video from the device. since clki will be the only incoming frequency reference, the encoder uses this signal to run its internal pll for derivation of the video color subcarrier (fsc). since pal and secam televisions are not lenient in accepting color subcarrier frequencies with more than 25 ppm error (i.e., fsc 330 hz), it is critical the data master maintain a very high level of accuracy for the incoming clock. in numerical terms, this means that the incoming clock should always remain within a window of {ideal clki} 25 ppm. as an example, for autoconfiguration mode #1, clki would have to reside in the range [29.499270 mhz < ideal clki = 29.500008 mhz < 29.500746 mhz.] tight control of the incoming digital clock ensures that the CX25870 generates an analog fsc of 4.433618 mhz 338 hz for pal-bghi or 4.250000 / 4.406250 mhz 338 hz for secam. actu al testing has found that excursions outside this range result in loss of color for pal and secam televisions and sometimes affect ntsc sets in the same manner. when the CX25870 is receiving an external clock, its serial bus is also dependent on this incoming signal. as a result, the data master should never disable the input clock. if this happens, even momentarily, the only way the encoder can recover is for the data ma ster to pin reset* the CX25870. the encoder will then be re-enabled as a timi ng master and respond again to serial commands transmitted by the data master. several other registers must be reprogra mmed to make this special type of interface work properly. consult your local conexant representative for technical assistance.
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-22 conexant 100381b 1.3.8 autoconfigurat ion and interface bits the default operation of the CX25870/871 is tied into its 44 autoconfiguration modes. autoconfiguring the device occurs when bits config[5:3] and config[2:0] in register 0xb8 are prog rammed to any state from 000000 to 101111. at the conclusion of this serial write, default values are copied from the CX25870/871?s internal rom into the most important timing registers that have the indices 0x38 and 0x76 to 0xb4, inclus ive. all other registers are not changed at the conclusion of an autoconfiguration mode. after an autoconfiguration command, the CX25870/871 device remains in the same interface it was in before the command execution. depending on which autoconfiguration mode# was initiated, th e CX25870/871 will expect to receive either a 320x200, 320x240, 640x400, 640x480, 720x400, 720x480, 720x576, 800x600, or 1024x768 active digital input frame and output a ntsc or a pal composite and/or s-video signal. see table 2-5 of this data sheet for a description of config[5:0] and appendix c for more detail on each autoconfiguration mode. using an autoconfiguration mode is th e easiest method for bringing up the most popular desktop, game/direct x, dos boot-up screen, and dvd resolutions with the encoder as both the timing and clock master. this is true even if the graphics controller cannot utilize the CX25870/871 in master mode but must use pseudo-master mode. to turn the direct ion of the syncs around so they are transmitted by the graphics controller and received by the CX25870/871 simply requires reprogramming the enco der via several serial writes. the interface bits that need to be changed are slaver, en_blanko, en_dot, and en_out. since the abilities of graphics controllers vary greatly, tables 1-7 through 1-12 have been compiled below to explain the relationship between the interface bits and the actual in terface itself. even more permutations of the following interfaces below are possible but tables 1-7 to 1-12 capture the six most popular architectures. table 1-7. master interface without a blank* signal (default immediately after any autoconfiguration command) interfaced used slaver (bit 5 of 0xba) ored with slave pin en_blanko (msb of register 0xc6) en_dot (bit 6 of register 0xc6) en_out (lsb of register 0xc4) master (default) blank* is an output from the CX25870/871 or blank* s not included as part of the interface. 0101
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-23 if the slave pin is tied to gnd, the state of the slaver bit dictates whether the CX25870/871 is the timing master or timing slave by controlling the direction of the hsync* and vsync* ports. in other words, slaver will determine whether the overall interface is master or pseudo-master. the slaver bit allows the graphics controller vendor to switch between master video timing and slave video timing through software so long as the slave pin (#51) is low. en_blanko is high (=1), signifying the CX25870/871's blank* port is an output or that no blank* sign al is used as part of the system. en_dot = 0 telling the CX25870/871 to use its internal counters to determine the active versus the blanking regions. en_out = 1 ensures there is a clock output (clko) from the CX25870/871 and also enables hsync* and vsync* outputs. if the slave pin is tied to gnd, the state of the slaver bit dictates whether the CX25870/871 is the timing master or timing slave by controlling the direction of the hsync* and vsync* ports. in other words, slaver determines whether the overall interface is master or pseudo-master. the slaver bit allows the graphics controller vendor to switch between master video timing and slave video timing through software so long as slave pin (#51) is low. en_blanko is low (= 0), signifying the CX25870/871's blank* port is an input. en_dot = 1 telling the CX25870/871 to use the blank* signal it is receiving to determine where active video starts (rising edge of blank*) and uses hactive register to determin e the start of the blanking region. en_out = 1 ensures there is a clock output (clko) from the CX25870/871 and also enables hsync* and vsync* outputs. table 1-8. master interface with a blank* input to the CX25870/871 interfaced used slaver (bit 5 of 0xba) ored with slave pin en_blanko (msb of register 0xc6) en_dot (bit 6 of register 0xc6) en_out (lsb of register 0xc4) master blank* signal transmitted to the CX25870/871 and received as an input. 0011 table 1-9. pseudo-master interface without a blank* signal interfaced used slaver (bit 5 of 0xba) ored with slave pin en_blanko (msb of register 0xc6) en_dot (bit 6 of register 0xc6) en_out (lsb of register 0xc4) pseudo master blank* is not included as part of the interface. 1101
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-24 conexant 100381b slaver bit = 1 so the CX25870/871 is the video timing slave. it expects to receive the syncs from the graphics controller. en_blanko is high(=1), signifying the CX25870/871's blank* port is an output or that no blank* sign al is used as part of the system. en_dot = 0 telling the CX25870/871 to use its internal counters to determine the active versus the blanking regions. en_out = 1 ensures there is a clock output (clko) from the CX25870/871. slaver bit = 1 so the CX25870/871 is the video timing slave. it expects to receive the syncs from the graphics controller. en_blanko is low (= 0), signifying the CX25870/871's blank* port is an input. en_dot = 1 telling the CX25870/871 to use the blank* signal it is receiving to determine where active video starts (rising edge of blank*) and where the blanking region starts (falling edge). en_out = 1 ensures there is a clock output (clko) from the CX25870/871. after an autoconfiguration command, the CX25870/871 expects active low vsync* and hsync* signals from the controller. the format of pixels at input of encoder needs to be 24-bit rgb multiplexed unless modifications are made to th e in_mode[3:0] 4-bit sequence. in addition to table 1-11 , another bit must be programmed manually with this interface. the most significant bit of CX25870/871 register 0xa0 must be set. this guarantees that en_xclk is high (=1) which will allow the CX25870/871 to accept clki as the pixel clock source. table 1-10. pseudo-master interface with a blank* input to the CX25870/871 interfaced used slaver (bit 5 of 0xba) ored with slave pin en_blanko (msb of register 0xc6) en_dot (bit 6 of register 0xc6) en_out (lsb of register 0xc4) pseudo master blank* signal transmitted to the CX25870/871 and received as an input. 1011 table 1-11. slave interface without a blank* signal interfaced used slaver (bit 5 of 0xba) ored with slave pin en_blanko (msb of register 0xc6) en_dot (bit 6 of register 0xc6) en_out (lsb of register 0xc4) en_xclk (msb of register 0xa0) slave blank* is not included as part of the interface. 11001
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-25 slaver bit = 1 the CX25870/871 is the video timing slave. it expects to receive the syncs from the graphics co ntroller. since the CX25870 is in slave mode, the hsync* and vsync* ou tputs will be three-stated and the CX25870/871 will be set up to receive these timing signals from the graphics controller. en_blanko is high (=1), signifying the CX25870/871's blank* port is an output or that no blank* sign al is used as part of the system. en_dot = 0 telling the CX25870/871 to use its internal counters to determine the active versus the blanking regions. en_out = 0: this ensures the clock ou tput port (clko) is three-stated from the encoder. after an autoconfiguration command, the CX25870/871 expects active low vsync* and hsync* signals from the controller. the format of pixels at input of encoder needs to be 24-bit rgb multiplexed unless modifications are made to th e in_mode[3:0] 4-bit sequence. in addition to table 1-11 , another bit must be programmed manually with this interface. the most significant bit of CX25870/871 register 0xa0 must be set. this guarantees that en_xclk will be high (=1) which will allow the CX25870/871 to accept clki as the pixel clock source. slaver bit = 1 so the CX25870/871 is the video timing slave. it will expect to receive the syncs from the graphics controller. since the CX25870 is in slave mode, then the hsync* and vsync* outputs will be three-stated and the CX25870/871 will be set up to receive these timing signals from the graphics controller. en_blanko is low (= 0), signifying the CX25870/871's blank* port is an input. en_dot = 1, telling the CX25870/8 71 to use the blank* signal it is receiving to determine where active video starts (rising edge of blank*) and the hactive register to denote where the blanking region starts. en_out = 0: this will ensure the clock output port (clko) is three-stated from the encoder. note: autoconfiguration mode #28 and #29 for ntsc and pal dvd playback place the encoder into slave interface where it expects a blank* input ( table 1-11 ). table 1-12. slave interface with a blank* input to the CX25870/871 interfaced used slaver (bit 5 of 0xba) ored with slave pin en_blanko (msb of register 0xc6) en_dot (bit 6 of register 0xc6) en_out (lsb of register 0xc4) en_xclk (msb of register 0xa0) slave blank* signal transmitted to the CX25870/871 and received as an input. 10101
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-26 conexant 100381b 1.3.9 adaptations for clo ck-limited master devices ideally, the graphics controller or pr oprietary asic, in combination with the CX25870/871, operates in either master or pseudo-master interface. occasionally, using either of the clock master configur ations is not possible because the master device does not have the capabilities of receiving a clock from the encoder nor can it synchronize the digital data with th is clock on its return. if either limitation exists, only slave interface can be used for the system configuration. often, within the slave interface, the data master can only generate certain discrete clock frequencies. this means the encoder ha s to make extra accommodations for normal tv out to occur. fortunately, the encoder does have the flexibility to adapt to almost any incoming clock frequency in the range from 20 mhz to 80 mhz. all that is required is to follow the procedure in table 1-13 which forces the encoder to accept a frequency through clki that does not match any CX25870/871 autoconfiguration frequency. once the CX25870/871?s 4-byte wide msc register is reprogrammed accordingly, the result is the generation of the correct color subcarrier frequency for ntsc or pal and corresponding proper s-video or composite tv output. table 1-13 and table 1-14 contain the procedures re quired for the encoder to accept a frequency through clki that is not equal but is close to the chosen CX25870/871 autoconfiguration mode cl ock frequency. completion of the steps contained in the two tables will modi fy the msc register and pll_int and pll_fract registers correctly and thus produce an accurate ntsc or pal analog output. table 1-13. adjustment to the CX25870/871 msc registers 1. what is input frequency to CX25870/871?s clki input from data master? 2. depending on answer to step 1, find an autoconfiguration mode th at has a frequency close to the incoming input frequency (within 1 mhz is preferred). 3. look up the clock frequency for the chosen autoconfiguration mode in appendix c of the CX25870/871 data sheet. 4. determine the scaling factor ?x? where x = input frequency to clki in put (usually from data master) autoconfiguration mode frequency as specified in appendix c 5. determine the autoconfiguration mode?s msc[31:0] value in hex by reading back the CX25870/871?s registers; 0xb4(=msb), 0xb2, 0x b0, 0xae(=lsb). these register values can also be found by looking them up in register c. the values de termined will have to be cascaded together. 6. convert the msc[31:0] 4-byte hexadecimal value to decimal. 7. divide the total found from step 6 by the scaling factor ?x? found from step 4. 8. convert the answer from step 7 to the hexadecimal format. this value should be comprised of a total of 4 bytes. the most significant byte will likely not change from the previous value in register msc[31:24]. other msc values may not change eith er but the least significant bytes should have definitely been modified. 9. program the bytes determined from step 8 into the CX25870/871?s msc[31:0] registers. write these bytes in order to registers 0xb4 (most significant byte = msc[31:24]), 0xb2, 0xb0, and 0xae (least significant byte = msc[7:0]).
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-27 1.3.10 input formats the device can convert a wide range of input formats to analog standard or hdtv television video formats. the input can be either noninterlaced or interlaced digital data from 320 x 200 to a maximum of 1024 x 768 pixels per frame for standard tv outputs. while generating hdtv outputs the device can accept greater than 1024 x 768 input frames. many other nonstandard input formats can be encoded as well. for deta iled information on the ccir601 mode, please refer to the dvd movie playback architectu re and solutions application note . this application note can be obtain ed from your local conexant systems sales office. for instructions on how to display nonstandard resolutions on the tv, request the ?supporting tv out with non-stan dard graphics input resolutions? application note from your local conexant systems sales office. table 1-14. adjustment to the pll_int and pll_fract registers 1. what is input frequency to CX25870/871?s clki input from data master? 2. depending on answer to step 1, find an autoconfiguration mode that has a clock frequency close to the incoming clki frequency (within 1 mhz is preferred). 3. look up the desired clock frequency for the chosen autoconfiguration mode in appendix c of the CX25870/871 data sheet. 4. determine the scaling factor ?x? where: x = input frequency to clki in put (usually from data master) autoconfiguration mode frequency as specified in appendix c 5. determine the pll_int value in hex by reading back the CX25870/871?s register 0xa0 for that autoconfiguration mode. this register valu e can also be found by looking it up in appendix c . 6. convert the pll_int regi ster value to decimal. 7. multiply the answer found in step 6 by 2 16 = 65536. 8. determine the pll_fract value in hex by reading back the CX25870/871?s register 0x9e and 0x9c. these two registers cascade to form the pll_fract[ 15:0] 2-byte value. these register values can also be found by looking them up in appendix c . 9. convert the 2-byte pll_fract register value to decimal. 10. from steps 7 and 9, add the pll_int and pll_fract decimal values. 11. multiply the total found from step 10 by the scaling factor ?x? found from step 4. 12. convert the answer from step 11 to the hexadecima l format. the value should be comprised of a total of three bytes. the most significant byte will like ly be the original pll_in t[7:0] byte from step 2. 13. program the bytes determined from step 12 into the CX25870/871?s pll_int[7:0] and pll_fract[15:0] registers. the mo st significant byte from step 12 is the new pll_int value. write this to register 0xa0. the 2 least significant bytes from step 12 is the new pll_fract value. write these bytes in order to regi sters 0xbe and 0xbc respectively.
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-28 conexant 100381b 1.3.11 input pixel timing the device can accept the input data in either rgb or ycrcb color spaces. data can be input either a full pixel at a time clocked in on the rising edge of clki only, or in various multiplexed modes, using both edges of clki. in ycrcb format, either 24-bit 4:4:4 data or 16-bit 4:2:2 data can be input. in rgb format, either 15-bit 5:5:5, 16 bit 5:6:5, or 24-bit rgb can be input. in 16-bit 4:2:2 ycrcb input format, multiplexe d y, cr, and cb data is input through the p[11:4] or p[7:0]input pins. the y data is input on the falling edge of clki. the cr/cb data is input on the rising edge of clki. the cb/y/cr/y sequence begins at the first active pixel. an addi tional 4:2:2 ycrcb input format maps y to p[19:12] and cr/cb multiplexed on p[11:4 ]. in 24-bit 4:4:4 ycrcb input format, multiplexed y, cr, and cb data is input th rough the p[11:0] inpu ts. both the rising and falling edge of clki sample the input data. in rgb input format, input data is sample d as 12 bits at a time in 24-bit rgb format or 8 bits at a time in 15/16 bit rg b format on both the rising and falling edge of clki. table 1-2 shows the data pin assi gnments for all available multiplexed input formats. in addition, all 24-bit formats, a 16-bit rgb fo rmat, and a 16-bit ycrcb format can utilize the nonmulti plexed clocking method. see table 1-3 for these pin-to-bit assignments. 1.3.12 ycrcb inputs (f or standard tv outputs) y has a nominal range of 16?235; cr and cb have a nominal range of 16?240, with 128 (80 hex) equal to zero. values of 0 and 255 are interpreted as 1 and 254, respectively. y values of 1?15 and 236?254, and crcb values of 1?15 and 241?254, are interpreted as valid linear values.
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-29 figure 1-8 illustrates the frequency response of the sub-sampling process. if 4:4:4 data is input, it is subsampled to 4:2:2 prior to overscan compensation and flicker filtering. the resulting 4:2:2 output must then be converted to yuv values and then scaled for the output range of the dacs. the my, mcr, and mcb registers must be programmed to perform this conversion . the scaling equations are as follows: my = (int) [v100/(219.0 * v fs ) * 2 6 + 0.5] mcr = (int)[(128.0/127.0) * v 100 * 0.877/(224.0 * v fs * 0.713 * sinx) * 2 6 + 0.5] mcb = (int)[(128.0/127.0) * v 100 * 0.493/(224.0 * v fs * 0.564 * sinx) * 2 6 + 0.5] where:v 100 = 100% white voltage (0.661 v for ntsc, 0.7 v for pal/secam) v fs = full scale output voltage (1.28 v) f sc = color subcarrier frequency (see table a-2 ) f clk = analog pixel rate sinx = sin ( f sc /f clk )/( f sc /f clk ) figure 1-8. decimation filter at fs=27 mhz 0 5 10 15 20 25 30 35 40 45 frequency (fs = 27 mhz) decibels (db) 0123456 chroma decimation filter 100381_005
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-30 conexant 100381b 1.3.13 rgb inputs (for standard tv outputs) with in_mode[3:0] set to a rgb mode, the encoder must receive digital gamma-corrected rgb data as an input. if this occurs, the rgb data will be converted to y/r-y/b-y as follows: y[9:0] = [int(0.299 * 2 10 ) * r[7:0]} + int(0.587 * 2 10 * g[7:0] + int(0.114 * 2 10 ) * b[7:0] + 2 7 ] * 2 -8 0 y[9:0] 1024 for 15 and 16 bit rgb input formats, individual r, g, and b values are left justified to eight bit numbers. after the initial conversion, the y/r-y/ b-y values are sub-sampled to 4:2:2 data prior to overscan compen sation and flicker filtering. the resulting 4:2:2 output must then be converted to yuv values and then scaled for the output range of the dacs. the my, mcr, and mcb registers must be programmed to perform this conversion. the scaling equations are: my = (int)[v 100 /(255 * v fs ) * 2 6 + 0.5] mcr = (int)[(128.0/127.0) * v 100 * 0.877/(127 * v fs * sinx) * 2 5 + 0.5] mcb = (int)[(128.0/127.0) * v 100 * 0.493/(127 * v fs * sinx) * 2 5 + 0.5] where:v 100 = 100% white voltage (0.661 v for ntsc, 0.7 v for pal) v fs = full scale output voltage (1.28 v) f sc = color subcarrier frequency (see table a-2 ) f clk = clki input frequency sinx = sin [(2 f sc /f clk )/(2 f sc /f clk )] for secam formulas see the secam section. 1.3.14 input pixe l horizontal sync the hsync* pin provides line synchroniza tion for the pixel inpu t data. it is an output in master interface and an input in slave and pseudo-master interface. in the master interface, it is a pulse two cl ki cycles in duration whose leading edge indicates the beginning of a new line of pixel data. the period between two consecutive hsync* pulses is h_clki clk cycles. the first active pixel should be presented to the device h_blanki minus the internal pipelined clock (5 clk cycles) after the leading edge of hsync*. the next h_active pixels are accepted as active pixels and used in the construction of the output video. in the slave interface the exact number of clocks per line (h_clki) must be provided as calculated for the desired over scan ratio. only the leading edge of hsync* is used, low times must be at least two clki cycles in duration. hsync* is clocked into the encoder by the rising edge of clki. the polarity of the hsync* signal is changed by the hsynci register bit. the default convention is active low.
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-31 1.3.15 input pixel vertical sync the vsync* pin provides field synchronization for the pixel input data. it is an output in master interface, and an in put in the slave and the pseudo-master interface. for noninterlaced input timing in mast er interface, vsync* is a pulse one horizontal line time in duration whose le ading edge indicates the beginning of a frame of input pixel data. the leading ed ge coincides with the leading edge of hsync*. the period of the pulses is v_linesi horizontal lines. the first line of active data should be presented to the device v_blanki lines after the leading edge of vsync*. the next v_activei lines are accepted as active lines and used in the construction of the output video. the CX25870/871 disregards lines after the leading edge of vsync* but before vsync* + v_blanki lines by not encoding them. in slave interface, the period must be exactly the frame rate of the desired video format. only the leading edge is used, and the high and lo w duration must be at least two clki cycles. the beginning of the frame of data is indicated by the next leading edge of hsync* coincident with or after the leading edge of vsync*. for interlaced input timing, only the slave interface is supported. the period must be exactly the frame rate of the desired video format. if the leading edge of hsync* and vsync* are coincident, that indicates the input is in odd field, the internal line counter is reset to line 1 at the leading edge of vsync*. if the leading edges of hsync* and vsync* are not coincident, and separated by a minimum of two clki cycles, this indicate s the input is an ev en field. in this case, the internal line counter is reset to line 2 at the beginning of the next line. only the leading edge of vsync* is used, and the high and low vsync* width must be at least two clki cycles. vsync* is clocked in by the rising edge of clki. the polarity of the vsyn c* input and output can be programmed by the vsynci register bit. the default conventi on is active low. the fld_mode bits allow further flexibility in hsync* and vsync* timing relationship. 1.3.16 input pixel blanking input pixel blanking can be controlled by either the blank* pin or by the internal registers. blanking can be prog rammed independently of master or slave interface using the en_blanko register bit. as an output (en_blanko = 1), pixel blanking is generated based on the active area defined by h_blanki, h_active, v_blanki, and v_activei registers. with en_blanko = 1, the blank* pin is output in the proper relationship to the syncs to indicate the location of active pixels. as an input (en_blanko = 0), when the blank* pin goes high, it indicates the start of active pi xels at the pixel input pins. in addition, the h_blanki register must be programmed properly. the duration of active data is still determined by the h_active register. blank* is clocked by the rising edge of clki. an additional function for the blank* pin is used if the en_dot register bit is set. if en_dot = 1, the blank* pin becomes an input whose rising edge defines the graphics controll er character clock boundary. this is used internally by the encoder to keep track of the exac t pixel count for cont rollers that cannot operate at pixel clock rates but instead operate at vga character clock rates. the polarity of the blank* input/output can be programmed by the blanki register bit. the default convention is active low.
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-32 conexant 100381b table 1-15 summarizes the direction of the blank* encoder in each interface. for more information refer to section 1.3.8 . 1.3.17 overscan compensation overscan compensation is the process by which the encoder converts the digital input lines to the appropriat e number of output lines for producing a full-screen image on the television receiver. this co nversion is done in accordance with the vertical scaling ratio (vsr). vsr is th e ratio of the number of input lines received to number of output lines generated by the CX25870 (i.e., 262.5 lines/field for ntsc and 312.5 lines/f ield for pal-bdghi and secam). using the correct amount of compensation in both the horizontal and vertical dimensions (at least 10 percent) will ensure that the entire digital image normally seen on the pc monitor is satisfactorily mapped to the analog television without any pixels or lines hidden in unviewable areas. increasing the horizontal overscan compensation (hoc) percentage while keeping the vertical overscan compensation (voc) percentage the same will have several effects on the vga encoder. first, the number of output clocks per line (h_clko) will increase. correspo ndingly, the clock frequencies shared between the data master and CX25870 (i.e., clko = clki) will increase. therefore, the original numb er of active pixels will be squeezed into a smaller analog video display region because the fre quency at which input data is clocked into the CX25870 has increased. since the CX25870 now processes active data at a faster rate than ccir601-only compatib le encoders, the grap hics controller will need to transmit more blank pixels per line (i.e., htotal must increase to match CX25870?s h_clki) to make up the difference. increasing the (voc) percentage whil e keeping the horizontal overscan compensation percentage the same will ha ve several different effects on the vga encoder. first, the h_clko total will stay the same as will the pixel rate (i.e., clki = clko). these parameters are dictated by the hoc value only. second, the number of total vertical input lines (v_linesi = data master?s vtotal) will increase, which will increase the internal vsr. the net result is that more active pixels and more active lines will be used to generate each output line. the only way for the graphics controll er to transmit thes e additional inpu t lines with the same clock frequency as before is to decrease the amount of blanked pixels per line. table 1-15. summary of allowable blank* signal directions by interface interface allowable direction of blank* master input or output pseudo-master input slave input
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-33 to support a custom overscan ratio, an entire set of over scan compensation calculations is required. this results in as many as 25 new register values for the CX25870. for ease of use, these equations are embedded into conexant?s programming application called super co ckpit. each computation is somewhat interdependent on the others but the ba sic overscan equations are as follows: (*) vsr = (v_linesi) / (# of total output lines per field) and (**) # blanked pixels = {[h_clko / vsr] ? h_active} for illustrative purposes, the calculations used to generate the 13.785 percent hoc percentage for autoconfiguration mode 0?640x480 rgb in, h_clko = 1792, ntsc output, are shown below: from appendix c (CX25870/871 data sheet): number of clocks necessary to latch in the v.s.r. # of input lines for every 1 analog output line = 1792 clks [i.e., h_clko] CX25870 must ensure input is 2x upsampled. therefore: # active clks per analog line = 2*(h_active) # active clks per analog line = 1280 active clks per analog line percent of input used to create active video area = {1 280 active clks / 1792 total clks} = 71.4286 percent therefore: (x) = active region percent of analog output line = 71.4286 percent (y) = active region percent of typical analog video for ntsc = 52.65556 s / 63.55556 s = (y) = 82.4945 percent of line is active ratio of [x/y] = {71.4286 percent / 82.4945 percent} = 0.862147 hoc percentage = 1?{ratio of [x/y]} hoc percent = 1?0.862147 = 13.785 percent = hoc percentage for autoconfiguration mode 0 as a result, 13.785 percent of the horizontal active region within each line of an ntsc signal will be forcibly blanked by the CX25870. for most tvs, this will resize the upsampled digital image properly so all of the pixels fit horizontally within the bezeled area of north american or japanese tvs. the 13.785 percent overscan percentage is equally distributed on either side of the horizontal active region (i.e., 13.785 percent / 2 = 6.89 percent extra blanking for the beginning and end of the line). the original 640 active pixels (i.e., h_active) will then be ?squeezed? into the remaining analog activ e region due to the faster pixel rate. the explanation of the vertical overs can percentage value is similar. for autoconfiguration mode #0, v_activeo is 212, which means there are 210 full active lines per field. the first and last lines are filtered lines that assist in smoothing the transitions into and out of the active re gion to avoid flickering and are not counted. any ntsc standard calls for 243 active lines per field, so 210/243 = 0.864198 of the vertical active region is used. this calculation yields a vertical overscan compensation percentage of 100?86.4198 = 13.5802 percent.
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-34 conexant 100381b flicker filtering and vertical and hori zontal overscan compensation are not supported in any interlaced rgb or ycrcb input format sent to the CX25870. interlaced input data is commonly used for dvd out from a mpeg2 decoder chip. because of th e data and image content ty pes, flicker filtering and overscan compensation are not necessary in this case. illustrations showing the before and after effects of overscan compensation can be found in figures 1-9 and 1-10 . figure 1-9. windows desktop image from encoder without overscan compensation 100381_072 active viewable area with no horizontal overscan compensation * a number of active pixels are hidden behind tv's bezel active viewable area with no vertical overscan compensation * a number of active lines are hidden behind tv's bezel note(s): overscan percentages taken from CX25870's autoconfiguration mode 0.
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-35 in figure 1-10 , the CX25870 overscan compensated the 640 horizontal active pixels of data to fit within the viewab le video region. with 13.78 percent hoc, the active data is cont ained within a 45.397 s. portion of time within each active line while the remaining 7.26 s (52.65556 s.?45.397 s.) part of the active region is blanked by the encoder. the net result of overscan compensation will be an interlaced ntsc, pal, or secam video image that fits within the bezel area of a tv monitor. correct choice of the hoc and vertical overscan compensation (voc) percentages is important so that no regions of the active input image will be hidden behind the plastic of the tv unit. various tvs require different hoc and voc values to fully utilize the entire viewable area of the tv. for the user?s convenience, conexant has generated appendix a in the CX25870/871 datasheet which lists many of the possible overscan ratios for the 3 major desktop resolutions (640x480, 800x600, and 1024x768) and the 2 most popular video outputs (ntsc and pal-bdghi). varying amounts of blanking would be required depending on the hoc and voc percentages an d active input resolutions. ultimately, the blanked regions would be dictated by the blank* signal itself and/or the internal pixel counter for the CX25870/871. ac tual transmission of null or blanked pixels is not necessary since the encoder ignores any data sent to it via the pixel input po rt within the blanked region s. only the active pixels need to be sent to the enco der from the controller during the digital active period. figure 1-10. windows desktop image from CX25870 with overscan compensation 100381_073 13.78 % / 2 = 6.89 % blanking on each side of tv 13.58 % / 2 = 6.79 % blanking on each side of tv note(s): overscan percentages taken from CX25870's autoconfiguration mode 0.
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-36 conexant 100381b figures a-1 through a-8 illustrate many of the allowable overscan compensation percentage pa irs for the major desktop resolutions and the most popular video outputs. these figures illustrate the minimum horizontal blanking times the data master must possess along with overscan compensation plots for pixel based data masters as well as 8-and 9-cycle character clock based graphics controllers. 1.3.18 standard flicker filtering to understand what flicker filtering is, one must understand two of the primary differences between the analog video standards used by tvs and the technology used in today?s computer monitors. first of all, computer monitors receive their video signal in a more basic, pristine form than tvs do. as discussed earlier, the video signal sent by a computer to its monitor is br oken into multiple electri cal components (red, green, blue and sync) while a tv signal has a ll necessary informatio n combined into a single composite signal or separate luma and chroma analog channels (s-video). in order to process this composit e signal, a tv must break it up into its original components, inevitably degr ading the picture qu ality and creating distortions. a second factor contributing to the decreased quality of images displayed on tv monitors is interlacing, a technique by which a complete tv picture is drawn in two passes from top to bottom on the picture tube. in interlacing, the first pass paints all the ?odd? lines and the second pass paints the ?even? lines. noticeable flicker occurs when the images in the od d lines are very different from the images in the even lines. as the odd and even lines are alternately displayed, the eye perceives the quick appearing and disappearing of visual information. this results the in the irritation called flicker. flicke r is especially noticeable when viewing thin horizontal lines that only take up a si ngle row within the odd or even field. if, for example, the line happens to be on an odd row, it totally disappears every time the even rows are displayed resulting in that item appearing and disappearing at the field rate on the tv. unlike tv monitors, computer monito rs paint an entire image in one pass from top to bottom, in a display format called noninterlaced or progressive. images displayed in a noninterlaced format do not suffer from the same flicker problems. for improved image quality and reduced flickering, the CX25870 contains a 5-tap or 5-line flicker filter for both the luma (f_sely[2:0]) channel and chroma (f_selc[2:0]) channe l. the conexant standard flicker-filter works by applying a mathematically weighted aver aging algorithm to the incoming pixels of data from different lines. this slightly alters the digital information that is processed and eventually converted to the odd and even lines of a tv picture so that the alternating lines are more simila r to each other. this way, when they appear and disappear in the interlacing pr ocess, the flicker is less noticeable. the more similar the lines are made to appear, the less flicker is visible.
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-37 however, the trade-off is that as flicke r is reduced, more and more information is being altered by the encoder and poten tially lost from the original picture. vertical resolution is therefore sacrificed and text clarity su ffers especially for small fonts below 10 points in size. for th is reason, the amount of flicker filtering is programmable and should be controllable by the end user. finding an optimal standard flicker filter setting for luma and chroma is somewhat subjective in nature and ensures that a pleasing image is seen on the television. unlike other encoders, the CX25870 integrates both a standard flicker filter and additional adaptive flicker filter . this implementati on allows for the preservation of small font text clarity and other challenging video images lost with only one filtering step. the adaptive feature eliminates more flicker with less loss of resolution because it is able to selectively apply more aggressive flicker reduction only to those portions of an im age where the effect will be beneficial. encoders lacking this adaptive filter apply the standard flicker filtering process to the entire screen. small text and icon s often become unreadable and thin, horizontal lines may completely disappear. the CX25870?s adaptive flicker filter prevents this from happening and is de scribed in its own section within this document. so long as progressive rgb or ycrcb data is received, the CX25870?s flicker filter is effective with any active resolution from 320x200 to a maximum of 1024 x 768. the flicker reduction is present on any interlaced video output such as ntsc, pal, or secam. the dis_ffilt register bit turns off the standard flicker filter. the vertical scaling can be disabled by setting the internal v_scale register to 4096 for a noninterlaced input. finally, the CX25870 supports up to 24-bit color processing, meaning that the converted image will feature the same depth of color as the original computer picture. 1.3.19 adaptive flicker filter adaptive flicker filtering is a new feature included with the CX25870/871. it allows the encoder to automatically alter the amount of flicker filtering based on the image being processed. the result is a high-quali ty optimized image because the perfect balance between vertical resolution and flicker reduction has been achieved. the adaptive flicker filter is enabled via the adpt_ff bit. there are four possible settings ranging from 2-lin e (most observable flicker, greatest vertical resolution) to 5-line (minimal observable flicker, moderate vertical resolution). the luminance and chrominanc e outputs are independent in terms of the level of adaptive flicke r filtering. when the adaptive flicker filter is on, the manual flicker filter is off and vice versa. vertical filtering in the cx25 870/871 serves three purposes: vertical polyphase interpolation filt ering to upsample the image data vertically. this increases the resolu tion and accuracy of the subsequent vertical downsampling requ ired to fit the entire image into the visible region of the television. anti-alias filtering to reduce aliasing artifacts when downsampling vertically. flicker filtering to reduce the flic ker produced when vertical high frequency content is displayed on an interlaced device.
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-38 conexant 100381b the vertical interpolation filterin g and vertical anti-alias filtering requirements are driven by the amount of vertical down scaling required, and do not vary substantially with image conten t. the flicker filt ering requirement, however, is dependent upon the image content. regions of the image with vertical high frequency content will flicker in proportion to the amplitude of that high frequency content. regions with high amplitude vertical high frequency content require substantial flicker filtering, but regions with low amplitude or no vertical high frequency content require little or no flicker filtering. for this reason, the CX25870/871 provides adaptive flicker filtering. it analyzes the image content to detect areas that require strong flicker filtering, and adjusts its vertical filtering to apply stro nger flicker filtering to those regions. this analysis and adjustment occurs on a pi xel by pixel basis, so each pixel in the output line has the optimal amount of flicker filtering applied to it. the adaptive_ff1 and adaptive_ff2 registers (0x34 and 0x36) configure the adaptive algorithm. the y_altff[1:0] and c_altff[1:0] fields allow the selection of the alternative (i.e., stronger) flicker filter to combine with the standard flicker filter selected by fiel ds f_sely[1:0] and f_selc[1:0] (register 0xc8). this creates an array of flicke r filters for the y channel and c channel respectively. the actual flicker filter applied for a given pixel output depends on the detection and location of any high amplitude verti cal high frequency content within the input samples that creates that output pixel. the amplitude of the high frequency content that triggers an adaptation of the flicker filter can be adjusted via th e y_thresh[2:0] and c_thresh[2:0] bit fields. the ffrtn bit offers two ways to combine the standard and alternate flicker filters to generate an array of flicker filters. the yselect bit allows the chroma channel flicker filter to be adapted based on the chroma channel or the y (i.e., luminance) channel content. note: neither standard nor adaptive flic ker filtering is supported by the CX25870/871 in noninterlaced vide o output formats (vga style rgb, hdtv 480p, 720p). table 1-16 summarizes recommended configurations of the adaptive flicker filter for various types of im age content and resolutions.
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-39 table 1-16. optimal adaptive and standard flicker filter settings for common pc applications and resolutions standard ff settings CX25870 adaptive ff settings register 0x34 register 0x36 desktop re solution/ video output type fsel_y fsel_c adpt_ff y_altff c_altff y_thresh c_thresh y_select ffrtn byycr chroma_bw final hex value final hex value 640x480 in, ntsc out 3-line 3-line on= checked 4-line 4-line 000 000 on on 1 0 9b c0 640x480 in, pal-bdghi out 3-line 3-line on=checked 4-line 4-line 100 100 on on 1 0 9b e4 800x600 in, ntsc out 4-line 4-line on= checked 5-line 5-line 010 010 off on 1 0 80 92 800x600 in, pal-bdghi out 4-line 4-line on=checked 5-line 5-line 010 010 on on 1 0 80 d2 1024x768 in, ntsc out 5-line 5-line o n=checked 5-line 5-line 110 110 on off 1 0 80 f6 1024x768 in, pal-bdghi out 5-line 5-line on=checked 5-line 5-line 110 110 on off 1 0 80 f6 web page resolution/ video output type fsel_y fsel_c adpt_ff y_altff c_altff y_thresh c_thresh y_select ffrtn byycr chroma_bw final hex value final hex value 640x480 in, ntsc out 4-line 3-line on=ch ecked 4-line 4-line 100 100 off off 1 0 9b 24 800x600 in, ntsc out 4-line 4-line on=ch ecked 5-line 5-line 010 010 off off 1 0 80 12 1024x768 in, ntsc out 5-line 5-line o n=checked 5-line 5-line 110 110 on off 1 0 80 f6 word processing resolution/vi deo output type fsel_y fsel_c adpt_ff y_altff c_altff y_thresh c_thresh y_select ffrtn byycr chroma_bw final hex value final hex value 640x480 in, ntsc out 3-line 3-line on= checked 4-line 4-line 010 010 off on 1 0 9b 92 800x600 in, ntsc out 4-line 4-line on= checked 5-line 5-line 100 100 on off 1 0 80 64 note(s): off means a '0' bit setting while on denotes a '1' bit setting.
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-40 conexant 100381b 1.3.20 vga registers involv ed in the tv out process timing constraints for the CX25870/871 are driven by the timing requirements of the analog video output (ntsc, pal, or secam) together with the active resolution and overscan compensation ratio (i .e., amount of blanking in the active region) of the television image. to expl ain what specific crtc or vga registers within the graphics controller need to be involved in displaying a nonstandard or desktop format on both a tv and crt, one can work backwards from those output signal timing requirements to determine the input ti ming requirements. each output field has a vertical blanki ng region and an active region. these regions are defined relative to the vertical sync pulse, horizontal sync pulse, given format (i.e., number of lines per field) , and a given pixel clock frequency (i.e., number of pixel clocks per line). within each line of the active region there is a horizontal blanking period (that includes a horizontal sync pulse) and an active period (where the image data is located). given those parameters, at least six registers within every generic graphics controller need to be changed for each active/total resolution. table 1-17 lists vga/crtc registers involved in tv out process. to achieve vga compatibility, the controller must manipulate some of its own vga register settings in order to produce a hi-quality dual display on both the computer monitor and tv. it should be noted that the encoder has no way of knowing that a different vga mode has been selected. as a result, it relies on the i 2 c ? -compatible master device to reconfig ure it via an autoconfiguration mode or complete register rewrite to make adjustments in its timing. when the two devices are programmed correctly, regardless of the interface, the required input hs ync*/vsync* to first input ac tive pixel or line spacing ?matches? the output hsync*/vsync* to first output active pixel or line spacing. when this occurs, th e graphics controller always transmits active data at the time the CX25870/871 expects to rece ive it. superior tv out quality is achieved only when this type of timing symmetry exists. table 1-17. vga/crtc registers involved in tv out process register name description start vblank/vsync* and end vblank/vsync* these vga registers work in combination with ea ch other to control the scan line at which the vertical blanking period begins a nd the point at which it ends. vactive dictates the specific number of active lines for the present digital frame. vtotal specifies the number of scan lines from one vsync* active to the next vsync* active pulse. the difference between vt otal and vactive is the amount of blanked lines. hblank/hsync* start and hblank/hsync* end this vga register set works in combination with ea ch other to control the value of the pixel or character clock counter where the hsync* signa l becomes active and the position at which hsync* becomes inactive. hactive dictates the specific numbe r of active pi xels per line. htotal specifies the number of pixel clocks or character clocks from one hsync* active to the next hsync* active pulse. in other wo rds, this is the total time re quired for both the displayed and nondisplayed portions of a single scan line. the differenc e between htotal an d hactive is the amount of blanked pixels per line.
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-41 1.3.21 output modes the encoder can generate output video as composite/y-c(s-video), yuv component, vga-style rgb, scart, component (yp r p b ) for hdtv, or rgb for hdtv. these outputs are selected by the out_mode[1:0] register bits in combination with the hdtv_en and en_scart bits. while the encoder is in vga style rgb, no color space conversion is possible from input to output. analog rgb is tr ansmitted from a digital rgb input and analog ycrcb is output from a digital ycrcb input. when outputting rgb with hdtv_en = 0, the device outputs vga/svga analog rgb with a bilevel sync. in this mode, the r, g, and b input data is fed to the dacs after the addition of the horizont al sync and, if the setup bit is one, the setup pedestal is added. the output currents are scaled so that the dacs output the proper 1 v full-scale (sync tip to peak white) levels for driving a crt monitor. the graphics controller must pr ovide all the timing control (hsync and vsync signals) for the monitor, which resu lts in the encoder operating as a slave in this case. only the p[23:0], blan k*, hsync*, and vsyn c* input pins and the rgb analog output pins are acti ve. the blank*, hsync*, and vsync* pins are automatically enabled as inputs in this mode. each of the four video signals generated by the out_mode[1:0] field can be multiplexed to any dac using the out_muxa[1:0], out_muxb[1:0], out_muxc[1:0], and out_muxd[1:0] register bits. to do this, program the 2-bit value representing the desired ty pe of output into the appropriate out_muxx[1:0] register. as an example, suppose a system requires composite video (i.e., 00) to be output from dac_a, chroma (10) on dac_b, luma (01) on dac_c, and composite video (00) on dac_d. this scheme could be accomplished by programming register 0xc6 with 0001 1000 binary or 18 hex. the lumadly[1:0] register bits control the amount of delay for the y_dly analog output. the allowable delay ranges from 0 (no delay) to 3 pixel clocks. all digital-to-analog converters are designed to drive standard video levels into a combined rload of 37.5 ? (doubly-terminated 75 ? loads). unused outputs should be disabled by setting the corresponding dacdisx bit to minimize the supply current or left as a no connect. disabling unused dac outputs reduces cross chroma distortion and improves picture quality. 1.3.22 analog horizontal sync the hsync_width[7:0] register determ ines the duration of the horizontal sync pulse. the beginning of the horizontal sync pulse corresponds to the reset of the internal horizontal pixel counter. the horizontal line rate is determined by h_clko[11:0]. the internal horizontal counter is reset to 1 at the beginning of the horizontal sync and counts up to h_clko. the sync rise and fall times are automa tically controlled. the sync amplitude is programmable over a range of values by sync_amp[7:0]. incrementing the sync amp by 1 increases the sync amp litude of the analog sync pulse by 30 millivolts.
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-42 conexant 100381b 1.3.23 analog vertical sync the analog vertical sync duration is selectab le as either 2.5 or 3 lines by register bit vsync_dur. if vsync_dur = 1, 3 lines are selected; if vsync_dur = 0, 2.5 lines are selected. the device automatically blanks the video from the start of the horizontal sync interval through the end of the burst, as well as the vertical sync to prevent erroneous video timing generation. 1.3.24 analog video blanking analog video blanking is controlled by the h_blanko, v_blanko, and v_activeo registers. together they define an active region where pixels are displayed. v_blanko defines the number of lines from the leading edge of the analog vertical sync to the first active output line per field. v_activeo defines the number of active output lines. h_blanko defines the number of output pixels from the leading edge of horizontal sync to the first active output pixel. h_active defines the number of active output pixels. the device automatically blanks video fr om the start of the horizontal sync interval through the en d of the burst, as well as the vertical sync interval to prevent erroneous video timing generation. 1.3.25 video output standards supported there are several bits (625line, setup, vsync_dur, pal_md, fm, dis_scrst), a pal pin, and various auto configuration modes, that control the generation of various video standards. (these are summarized in table 1-18 .) they allow the generation of all the different ntsc, pal, and secam video standards. the aforementioned bits co ntrol the specific encoding process parameters. it is likely other registers ma y need to be modified to meet all the video parameters of the particular vide o standard. video timing diagrams are illustrated in figures 1-11 through 1-22 . these show typical events that occur for each type of video format.
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-43 table 1-18. important bit settings for various video outputs video output bit ntsc-m ntsc- japan pal- bdghi pal-n pal-nc pal-m pal-60 secam- b, g, h (3) secam- d, k, k1 (2) secam-l (1) vsync_dur110101100 0 625line 001110011 1 setup 100101000 0 pal_md 001111100 0 dis_scrst000000011 1 fm 000000011 1 note(s): (1) secam-l used primarily in france. (2) secam-d, k, k1 used primarily in russia and eastern european nations. (3) secam-b, g, m used primarily in the middle east. (4) other CX25870 registers and bits must be reprogrammed to generate diffe rent video outputs. the bits in table 1-18 are the most important settings.
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-44 conexant 100381b figure 1-11. interlaced 525-line (ntsc) video timing note(s): smpte line numbering convention is used rather than ccir624. 22 7 6 5 4 3 burst phase 2 1 525 524 523 analog field 1 start of vsync analog field 2 272 271 270 269 268 267 263 262 261 266 265 264 285 analog field 3 burst phase analog field 4 burst begins with positive half-cycle burst phase = reference phase = 180? relative to b?y burst begins with negative half-cycle burst phase = reference phase = 180? relative to b?y 89 10 22 7 6 5 4 3 2 1 525 524 523 89 10 272 271 270 269 268 267 263 262 261 266 265 264 285 reset* 100381_006
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-45 figure 1-12. interlaced 525-line (pal-m) video timing 22 7 6 5 4 3 burst phase 2 1 525 524 523 analog field 1 start of vsync* analog field 2 272 271 270 269 268 267 263 262 261 266 265 264 analog field 3 burst phase analog field 4 89 10 7 6 5 4 3 2 1 525 524 523 89 272 271 270 269 268 267 263 262 261 266 265 264 burst phase = reference phase = 135? relative to u pal switch = 0, +v component burst phase = reference phase + 90? = 225? relative to u pal switch = 1, ?v component 11 12 22 11 12 285 274 273 285 274 273 10 reset* 100381_007
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-46 conexant 100381b figure 1-13. interlaced 625-line (pal-b, d, g, h, i, nc) video timing (fields 1?4) 24 7 6 5 4 3 ? u phase 2 1 622 621 620 analog field 1 start of vsync 625 624 623 23 analog field 2 337 320 318 317 316 315 314 309 308 312 311 336 319 337 320 317 316 315 314 308 313 312 311 336 319 310 313 309 318 310 24 7 6 5 4 3 2 1 622 621 620 625 624 623 23 field one field two field three field four burst blanking intervals burst phase = reference phase = 135? relative to u pal switch = 0, +v component burst phase = reference phase + 90? = 225? relative to u pal switch = 1, ?v component analog field 3 analog field 4 reset* 100381_008
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-47 figure 1-14. interlaced 625-line (pal-b, d, g, h, i, nc) video timing (fields 5?8) 24 7 6 5 4 3 ? u phase 2 1 622 621 620 analog field 5 start of vsync 625 624 623 23 337 320 318 317 316 315 314 309 308 312 311 336 319 337 320 317 316 315 314 308 313 312 311 336 319 310 313 309 318 310 24 7 6 5 4 3 2 1 622 621 620 625 624 623 23 field five field six field seven field eight burst blanking intervals burst phase = reference phase = 135? relative to u pal switch = 0, +v component burst phase = reference phase + 90? = 225? relative to u pal switch = 1, ?v component analog field 6 analog field 7 analog field 8 reset* 100381_009
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-48 conexant 100381b figure 1-15. interlaced 625-line (pal-n) video timing (fields 1?4) 24 7 6 5 4 3 2 1 622 621 620 625 624 623 23 337 320 318 317 316 315 314 309 308 312 311 336 337 320 317 316 315 314 308 313 312 311 336 24 7 5 4 3 2 1 621 620 625 624 623 23 ? u phase analog field 1 analog field 2 field one field two field three field four burst blanking intervals burst phase = reference phase = 135? relative to u pal switch = 0, +v component burst phase = reference phase + 90? = 225? relative to u pal switch = 1, ?v component analog field 3 analog field 4 reset* vsync* 310 309 622 310 313 319 6 318 319 1000381_010
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-49 figure 1-16. interlaced 625-line (pal-n) video timing (fields 5?8) 24 7 6 5 4 3 ? u phase 2 1 622 621 620 625 624 623 23 337 320 318 317 316 315 314 309 308 312 311 336 319 337 320 317 316 315 314 308 313 312 311 336 319 310 313 309 318 310 24 7 6 5 4 3 2 1 622 621 620 625 624 623 23 field five field six field seven field eight burst blanking intervals burst phase = reference phase = 135? relative to u pal switch = 0, +v component burst phase = reference phase + 90? = 225? relative to u pal switch = 1, ?v component analog field 6 analog field 7 analog field 8 analog field 5 vsync* 100381_011
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-50 conexant 100381b figure 1-17. noninterlaced 262-line (ntsc) video timing 10 21 9 8 7 6 5 4 3 field 1 2 1 262 261 start of vsync burst begins with positive half-cycle burst phase = reference phase = 180? relative to b-y burst begins with negative half-cycle burst phase = reference phase = 180? relative to b-y 100381_012 figure 1-18. noninterlaced 262-line (pal-m) video timing burst begins with positive half-cycle burst phase = reference phase = 180? relative to b-y burst begins with negative half-cycle burst phase = reference phase = 180? relative to b-y 10 21 9 8 7 6 5 4 3 2 1 262 261 start of vsync 11 12 field 1 100381_013 figure 1-19. noninterlaced 312-line (pal-b, d, g, h, i, n, nc) video timing 23 7 6 5 1 312 311 310 309 308 start of vsync 23 4 reset* 24 burst phase = reference phase = 135? relative to u pal switch = 0, +v component burst phase = reference phase + 90? = 225? relative to u pal switch = 1, ?v component 100381_014
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-51 figure 1-20. interlaced 625-line (secam-b, d, g, k, k1, l, m) video timing (fields 1-4) 100381_091 d r d r d r d r d r d b d r d b d r d b d b d r d b d r d b d b reset* end of the preceding 4-field sequence analog field 1 analog field 2 analog field 3 analog field 4 start of vsync 621 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 622 623 624 625 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 621 622 623 624 625 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 note(s): 1. d r and d b color subcarrier signal sequences over four consecutive fields shown above. 2. d r color subcarrier frequency is 4.406250 mhz. 3. d b color subcarrier frequency is 4.250000 mhz.
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-52 conexant 100381b 1.3.26 subcarrier generation the device uses a 32-bit-word to synt hesize the subcarrier. the value of the subcarrier increment required to generate the desired subcarrier frequency is found with the following equations: ntsc: msc[31:0] = int((455/(2*h_clko)) *2 32 + 0.5) pal: msc[31:0] = int((1135+1/625)/h_clko)*2 32 + 0.5 secam: msc_db[31:0] = int((272/(2*h_clko)*2 32 + 0.5) msc_dr[31:0] = int((272/(2*h_clko)*2 32 + 0.5) where:h_clko is the number of output clocks/line (this is register 0x76 and the low nibble of 0x86). this allows the generation of any desi red subcarrier for any desired video standard. the 32-bit subcarrier increment must be loaded by the serial interface before the subcarrier is enabled. the device is reset to disable chroma until the last byte of the 32-bit in crement loads, at which time the chroma is enabled, unless the dchroma bit is set. in order to prevent any residual errors from accumulating, the subcarrier dto (discrete time oscillator) is reset every four fields for ntsc formats and every eight fields for pal formats. for best quality in secam, the dis_scrst bit should be set preventing a subcarrier phase reset at the beginning of each color field sequence. furthermore, the secam subcarrier is generated on lines 23-310 and 336-623 automatically unless disabled by the prog_sc bit. 1.3.27 subcarrier phase reset/offset in order to maintain correct sc-h phasing, the subcarrier phase is set to 0 degrees on the leading edge of the analog vertical sync every four (ntsc) or eight (pal) fields, unless the dis_scrst (bit four of regi ster 0xa2) is set to a logical 1. this is true for both interlaced and noninterlaced outputs. the subcarrier phase can be adjusted from the nominal 0 degrees ph ase by the phase_off[7:0] register, where each lsb change corresponds to a 360/256 = 1.406 degrees change in the phase. setting dis_scrst to 1 may be useful in situations where the ratio of clk/2 to hsync* edges in a color frame is noninteger, which could produce a significant phase impulse by resetting to 0.
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-53 1.3.28 burst generation the subcarrier burst generation is a function of the video standard (e.g., ntsc, pal, or secam), the subcarrier frequenc y increment (msc[31:0]), and the burst horizontal begin and end register settings (hburst_begin[7:0] and hburst_end[7:0]). to calculate the value of hburst_end[7:0] subtract 128 from the desired location in clock cycles. the burst will automatically be blanked during the horizontal sync preventing invalid sync pulses from being generated. burst blanking is automatically controlled by the selected video format. burst rise and fall times are automatically generated by the device. the burst amplitude is programmed by the bst_amp[5:0] field. 1.3.29 video amplitude scal ing and sinx/x compensation both the luminance and chrominance video amplitudes can be scaled by the mcr, mcb, and my registers. this allo ws various colormetry standards to be achieved, and can also be used to boost the chroma to compen sate for the sin x/x loss of the dacs. appendix a show the range of values achievable and values for various video formats. the dac output response is a typica l sinx/x response. for the composite video output, this results in a slightly lower than desired burst and chroma amplitude value. this is compensated for, to some extent, by choosing an output filter that boosts the frequency response slightly. another method which can be used effectively, and is used by default in the auto configuration modes, is to boost the burst and chroma gain as programmed by the bst_amp and mcr/mcb register values by a factor of(x/sinx). the amount of sinx/x amplitude reduction is calculated by: sinx/x = sin ( * fsc/fclk) / ( * fsc/fclk) fsc = desired subcarrier burst frequency fclk = present input clock frequency 1.3.30 chrominance disable the chrominance subcarrier can be turned off by setting the dchroma bit to a logical 1. this disables the subcarrier burst as well, providing luminance-only signals on the cvbs output and a static blank level on the chrominance output.
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-54 conexant 100381b 1.3.31 field pin output like its predecessor, the bt868/869, the CX25870/871 includes a field pin output. this signal is output only and is accessed through pin #37. the frequency of the field pin is 30 hz during an ntsc video output, and 25 hz throughout a pal or secam video output. the only programming step required to obtain the field output is to serially write the en_out bit to 1. the purpose of this signal is to prov ide a digital ttl compatible output which tracks the analog interlaced field presen tly being transmitted by the CX25870/871 dacs. the peak-to-peak ampl itude of this output will be from 0 v to the level present on the vdd_co and vddl pins. if these pins are tied to 3.3 v, then the field high state is transmitted at a 3.3 v level. if these pins are tied to 1.8 v or lower voltage, then the field high state is transmitted at a 1.8 v or lower level. the logical 0 level from field will always be gnd/vss regardless of the logical 1 voltage. the field output tran sitions after the rising edge of clki, two clock cycles following the leading edge of the digital hsync* input or output. figure 1-21 shows the relationship between the field and composite (cvbs) outputs and vsync* input for ntsc. figure 1-22 illustrates this same relationship for pal. figure 1-21. field pin output timing diagram (ntsc-m, j, 4.43) *fieldi bit = 0 22 7 6 5 4 3 2 1 525 524 523 analog field 1 = odd start of vsync* analog field 2 = even 272 271 270 269 268 267 263 262 261 266 265 264 285 89 10 reset* 100381_094 composite output composite output field pin output field pin output
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-55 by default, the internal fieldi bit will be 0 which forces the CX25870 to transmit a logical 1 during transmission of an even field and logical 0 for the period of an odd field. to change the field polarity, reprogram the fieldi bit. if the CX25870/871 is the timing master and sends out hsync* and vsync*, then after a power-on, pin, or ti ming reset (setting of bit 7, register 0x6c), the encoder and the flicker filter port ions of the device start at line 1, pixel 1 of their respective timing generation. for the CX25870/871, this means the odd field is always the first field conveyed after a power-on reset, pin reset, or timing reset. when the CX25870 receives an interlaced data format, its field pin represents only the output field presen tly being generated by the on-chip dacs. when the CX25870 receives progressive (i.e., noninterlaced) frames which have no field associated with it, the CX25870?s input timing generator still keeps track of frames received. as a result, after th e entire second frame has been received, the input and encoder sections become resynchronized. this re-synchronization is done through an internal frame sync si gnal. this action, in turn, forces the CX25870 to the beginning of the odd field and changes the field pin back to its odd state. if the CX25870/871 is the timing sl ave (i.e., it accepts hsync* and vsync*) receiving a power-on reset, pin reset, or timing reset (register 0x6c, bit 7) causes the input timing generator to send the encode r the aforementioned frame sync. this sets the encoder to th e beginning of the odd field which is denoted through the field pin. the first digital hsync* and vsync* combination then corresponds to the en coder?s even output field. the second digital hsync* and vsync* combinatio n will again cause a frame sync and the encoder will start sending the odd field both from its dacs and field pin. this odd?even?odd?even ? field sequence continue s indefinitely. figure 1-22. field pin output timing diagram (pal-b, d, g, h, i, n, nc) 24 7 6 5 4 3 2 1 622 621 620 analog field 1 start of vsync* 625 624 623 23 analog field 2 337 320 318 317 316 315 314 309 308 312 311 336 319 310 313 reset* 100381_095 composite output composite output field pin output *fieldi bit = 0 field pin output
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-56 conexant 100381b 1.3.32 buffered crystal clock output the buffered crystal clock output (xtl_bfo) pin provides a buffered output (0 v to 3.3 v peak-peak) of whatever frequency is found between the CX25870?s xtalin and xtalout pins. this signal can then be used as a much more accurate input clock to the graphics cont roller because controll ers typically utilize clock sources with errors between 75?150 ppm. this implementation ultimately results in better vga picture quality becau se the clock driving the data master is within the same tolerance (i.e ., 25 ppm) as the tv out en coder. this can also lead to a considerable savings in cost, comp onent count, and pc board space because the crystal attached to the data mast er has been completely eliminated. on power-up, the encoder will transmit a 0 to 3.3 v signal at a frequency equal to the frequency of the crystal found between the xtalin and xtalout ports. the tolerance of the xtl_bf o signal will match the tolerance found within the encoder?s crystal. the CX25870 was designed to expect a 13.500 mhz 25 ppm crystal. as a result, all the pll_int and pll_fract register values found within each CX25870 autoconfiguration mo de possess this set of default values. the CX25870 does have the flexibility to support an alternate 14.31818 mhz crystal with a tolerance of 25 ppm. to switch the encoder to operate with this crystal frequency, install an appropriate crystal and crystal circuit between the xtalin and xtalout ports and set the 14 318_xtal bit to 1. enabling this bit translates the 13.500 mhz-dependent auto configuration registers to their new 14.31818 mhz settings. for CX25870 designs, a small (e.g., 33 ? ) series resistor should be added to xtl_bfo, as close as possible to the signal source device. this reduces overshoot and undershoot on this signal as it changes states. the buffered crystal clock output pin should be floated if not used. disabling the xtl_bfo pin is possible through the xtl_bfo_dis bit. 1.3.33 noninterlaced output when the CX25870/871 is programmed for noninterlaced video out via the ni_out bit, it always transmits the odd field. the field pin will continue to change state on the leading edge of the analog vertical sync. a 30 hz offset should be subtracted from the color subcarrier frequency while in ntsc mode so that the color subcarrier phase is inverted from field to field. the transition from interlaced to noninterlaced in master interf ace occurs during odd fields to prevent synchronization disturbance. note: consumer vcrs can record noninterlaced video with minor noise artifacts, but special effects (e.g., s can >2x) may not function properly.
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-57 1.3.34 closed captioning (cc) the CX25870/871 encodes ntsc/pal?m closed captioning on scan line 21, and ntsc/pal?m extended data services on scan line 284. four 8-bit registers (ccf1b1, ccf1b2, ccf2b1, and ccf2b2) provide the data while bits eccf1 and eccf2 enable display of the data. a logical 0 corresponds to the blanking level of 0 ire, while a logical 1 corresponds to 50 ire above the blanking level. closed captioning for pal?b, d, g, h, i, n, nc is similar to that for ntsc. closed-caption (cc) encoding is performed for 625-line systems according to the system proposed by the national captioni ng institute; clock and data timing is identical to that of ntsc system, except that encoding is provided on lines 22 and 335, for closed captioning and ex tended data services, respectively. the CX25870/871 generates the clock run-in and appropriate timing automatically. pixel inputs are ignored during cc encoding. see fcc code of federal regulations (cfr) 47 section 15.119 (10/91 edi tion or later) for programming information. the eia608 standard describes ancillary data applications for field 2 line 21 (line 284). when ccf1b2 is written, ccstat_o is set; when ccf2b2 is written, ccstat_e is set. after the cc bytes for the odd field are encoded, ccstat_o is cleared; after the cc bytes for th e even field are encoded, ccstat_e is cleared. if the eccgate bit is set, no fu rther encoding is performed until the appropriate registers are written again; a null is transmitted on the appropriate cc line in that case. if the eccgate bit is not set, the user must rewrite the cc registers prior to reaching the cc line; otherwise the last bytes are re-encoded. the cc data bytes are double-buffered to prevent loss of data during the encoding process. pseudo-code that can be used to create a software function for closed caption encoding is included as appendix d .
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-58 conexant 100381b 1.3.35 wide screen signaling (wss) the CX25870/871 supports the wss methods outlined in the eiaj cpr-1204 and itu-r bt.1119 standards. three serial interface registers control wss data insertion. for 525 line ntsc systems, tw o bits enable the insertion of the wss bit data on lines 20 and 283. the ewssf1 register bit controls line 20 and ewssf2 controls line 283. tw enty bits are used to insert the 14 bits of payload, plus six bits of crc data. crc data is not computed and must be inserted by the user. for 625 line pal and secam systems, ws s data insertion is only specified for line 23. in this case, the ewssf1 regi ster enables wss data insertion on line 23 and ewssf2 is ignored. only 14 bits of payload are specified for 625 line pal and secam systems. no crc is gene rated, therefore bits wssdat[20:15] are ignored in these systems. wssinc[19:0] specifies the incrementa l value of the pq ratio counter to generate the desired wss waveform. the increment value is found by: 525 line: wssinc[19:0] = 2 20 / (2.234*10 -6 *f clk ) 625 line: wssinc[19:0] = 2 20 / (200*10 -9 *f clk ) where:f clk = clki frequency = clko frequency. figure 1-23 illustrates a typical wss signal , where wssdat[14:1] = 0x00. note: wss uses biphase coding of its data bits. the amplitude of the wss pulses is 500 mv above black when high an d black when low. for further wss details, see specification ets 300294 or itu-r bt.1119 . figure 1-23. typical wss analog waveform (ntsc) 14 data bits start code run-in 5.86 s (ntsc) bit 14 bit 1 0.5 v 0.0 v 100381 040 ntsc: field 1, line 20 field 2, line 20 pal: field 1, line 23
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-59 the CX25870 does not support the cgms/a standard for analog pal or analog ntsc video systems. cgms st ands for copy generation management system whereby scan line 23 of pal field 1 or lines 20 and 283 of ntsc video outputs contains a data burst which deta ils the signal format. the burst also specifies the aspect ratio, type of enhanced services, and subtitle location for the tv to use during the broadcasted show. in addition to the details about the signal format, the cgms bits can indicate whether a recording device can make no copies, one copy, or unlimited copies. if no copies are allowed, the recording device will not make a copy. if a single copy is allowed, the recording device will make one copy and change the cgms data to indicate that no future copies can be made from the native content. the major reasons the CX25870 does not support the analog method of cgms/a are as follows: no movie studio even considers the no tion of allowing the user to make a single copy. all dvds released from the movie industry now enable the macrovision copy protection system so it is impossible to make any copies of dvds in the analog domain. there are no plans for dvd content providers to allow users to make limited copies of their intellectually copyrighted material. some aspects of the cgms/a system are not pirate-proof and can be disabled remotely. the cgms/a standard appears to be a vendor rather than a dvd consortium mandate. only a few dvd play ers have this feature now, and it is expected that they will abandon this as newer versions of the macrovision standard are released or a tamper -proof version of cgms exists. 1.3.36 chrominance an d luminance processing once the input data is converted to internal yuv format, the y and uv components are filtered and upsamp led to the system clock frequency. the luminance signal is always low-pa ss filtered using the upsampling filter response illustrated in figure 1-24 . additional peaking or reduction filters can be enabled (see figures 1-25 , 1-26 , and 1-27 ), using the pkfil_sel[1:0] register field. the peaking filters are optimized for high bandwidth frequency response, and optimal picture quality. the default chrominance filter response is illustrated in figure 1-28 , but an alternate wide bandwidth response ca n be selected using register bit chroma_bw, as illustrated in figure 1-29 . figure 1-30 illustrates the secam pre-emph asis filter response for the modulated chrominance signal.
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-60 conexant 100381b figure 1-24. luminance upsampling filter figure 1-25. text sharpness (luminance upsampling) filter with peaking options figure 1-26. close-up of text sharpness (luminance upsampling )filter with peaking and reduction options 0 2 4 6 8 10 12 0 amplitude in db frequency in mhz 100381_044 ?10 ?20 ?30 ?40 ?50 ?60 ?70 ?80 100381_045 0246 8 10 12 0 amplitude in db frequency in mhz ?10 ?20 ?30 ?40 ?50 ?60 pkfil_sel=00 pkfil_sel=11 100381_046 0 1 2 3 4 5 6 7 8 amplitude in db frequency in mhz 0 ?5 ?10 ?15 ?20
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-61 figure 1-27. zoom-in of text sharpness (luminance peaking) filter options figure 1-28. chrominance filter (chroma_bw = 0) - default figure 1-29. chrominance wide bandwidth filter (chroma_bw = 1) 0 1 2 3 4 5 6 0 0.5 1 1.5 2 2.5 3 3.5 4 amplitude in db frequency in mhz 100381_048 100381_049 0 0.5 1 1.5 2 2.5 3 3.5 4 0 amplitude in db frequency in mhz ?10 ?20 ?30 ?40 ?50 ?60 100381_050 0 1 2 3 4 5 6 frequency in mhz amplitude in db ?10 0 ?20 ?30 ?40 ?50 ?60
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-62 conexant 100381b 1.3.37 color bar and blue field generation the CX25870/871 has two internal color bar generators. preflicker filter color bars are enabled by setting the ffcbar bit to a logical 1. postflicker filter color bars are enabled by setting the ecbar bit to a logical 1. note: ffcbar color bars are optimized fo r rgb input mode and ecbar color bars are optimized for ycrcb input mode. the device uses the h_blanko register value to determine the starting point of the color bars, and the h_active regist er value to determine the width. eight bars are displayed, with th e colors and amplitudes being generated internally. the pixel inputs (p23?p0) are ignored in color bar mode. the CX25870/871 must be programmed with the appropriate my, m cr, and mcb register values for the desired input format, rgb or ycrcb. the CX25870/871 also produces a blue field by setting register bit eblue to 1. pixel inputs are ignored while any of the color generation wave forms are being produced. figure 1-30. secam high frequency pre-emphasis filter 3.5 4 4.5 5 0 2 4 6 8 1 0 1 2 1 4 1 6 frequency in mhz amplitude in db 100381_051
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-63 figure 1-31 and tables 1-19 and 1-20 illustrate the voltage amplitudes for the different color bar outputs. figure 1-31. composite and s-video format (internal colorbars) white yellow cyan green magenta red blue black blank level a wht a yel a cyn a grn a mgt a red a blu a blk a blk m blk m wht a sync m yel m cyn m grn m mgt m red m blu a wht a yel a cyn a grn a mgt a red a blu a sync m b m yel m blu m cyn m grn m mgt m red composite s video y c m b 100381_043 note(s): 1. a is the dc (luminance) amplitude referenced to black, except for a blk and a sync , which are referenced to blank. 2. m numbers are the peak-to-peak amplitudes of the subcarrier waveform. x x table 1-19. composite and luminance amplitude y and composite amplitudes a sync a wht a yel a cyn a grn a mgt a red a blu a blk ntsc-m (volts) ? 0.286 0.661 0.441 0.347 0.292 0.203 0.149 0.054 0.0536 ntsc-j (volts) ? 0.286 0.714 0.477 0.375 0.316 0.220 0.161 0.059 0 pal-b (volts) ? 0.300 0.700 0.465 0.368 0.308 0.217 0.157 0.060 0 note(s): a x is the dc (luminance) amplitude referenced to black, except for a blk and a sync , which are referenced to blank.
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-64 conexant 100381b 1.3.38 ccir656 mode operation data transmitted from mpeg -2 video decoders or vari ous multimedia processors is often done in a format called ccir656 . this format is si milar to the ccir601 in many ways but is unique in that the video sync information is embedded as codes in the data stream. as a result, no digital hsync or vsync signals are required as part of the physical interf ace between the timing master and slave devices. applications for ccir656 typicall y include consumer appliances such as video cd players, dvd players, set-to p boxes, and mpeg add-in cards where pin counts are limited. the actual digital ccir656 input data delivered to the CX25870/871 is interlaced 4:2:2 ycrcb over ei ght physical lines. in addition, there are two timing reference codes, one at the beginning of each video data block (start of active video, sav) and one at the end of each video data block (end of active video, eav). these timing reference values are digital words consisting of a unique 4-word sequence that conveys when the active video starts and ends. the ccir656 compliant master device embeds both sav and eav codes into the stream where appropriate. while in ccir656 mode, the CX25870/871 acts as the slave device (both clocking and timing). an illustration of this correct connection scheme is shown in figure 1-32 . table 1-20. composite and chrominance magnitude c and composite magnitudes m b m wht m yel m cyn m grn m mgt m red m blu m blk ntsc-m (volts) 0.286 0 0.444 0.630 0.589 0.589 0.629 0.444 0 ntsc-j (volts) 0.286 0 0.480 0.681 0.636 0.636 0.681 0.480 0 pal-b (volts) 0.300 0 0.470 0.663 0.620 0.620 0.664 0.470 0 note(s): m x numbers are the peak-to-peak amplit udes of the subcarrier waveform. figure 1-32. CX25870/871 connection to ccir656-compatible master device mpeg2 decoder clki p[7:0] 27 mhz clock 8 4:2:2 ycrcb composite #1 luma chroma composite #2 CX25870/cx871 100381_060
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-65 while in ccir656 mode, the encoder adhe res to all input guidelines specified in the itu-r bt.656-3 standard. this specification was developed for the transmission of color video signals in ycrcb format at a pixel rate of 27.000 mhz without the use of dedi cated timing reference signals. to display a dvd movie on a tv and co mputer monitor simu ltaneously with high-quality mpeg2 image format, the CX25870/871 must be integrated into the hardware design. next, actual ccir656 data must be sent from a mpeg2 decoding master device directly to the CX25870/871 encoder. finally, various software steps are necessary so the encode r switches to its slave interface and is set up to accept the interlaced ycrcb data and video timing reference codes. the first programming step is to configure the CX25870/871 to accept interlaced 4:2:2 ycrcb data with an activ e resolution of 720x480 and output a standard ntsc video output. the pertinent set of conditions for this option are: given this set of conditions, autoconfigur ation mode 28 is a perfect fit. as a result, simply use the mpeg2 decoders se rial bus mastering ability to program the CX25870/871s config[5:0] field with a binary value of 011100. this translates into writing a hexadecimal numb er of 0x34 to regi ster 0xb8. once the encoder acknowledges this write to its au toconfiguration register, it automatically loads the appropriate values for this type of dvd config uration into its register indices from 0x76 to 0xb4 , including register 0x38. the exact data transferred into these registers is contained in appendix c . after completion of the autoconfigur ation command, the encoder expects to receive interlaced 4:2:2 ycrcb data from the clock and timing master device at a rate of 27.000 mhz with blanking regions being defined by hsync* and vsync*. since these external signals, by definition, do not exist in ccir656 mode, a second and final programming step is required. after enabling autoconfigur ation mode 28, the progra mmer must make sure to set (=1) the e656 bit. this is bit 6 of register 0xd6 and enables a ccir656 input to be received via the CX25870/871s p[7:0] port. once this is done, the encoder deciphers digital blanking through the sav and eav codes and disregards the synchronization signals. only after the completion of these steps will a dvd stream be properly encoded and rendered onto the television by the vga encoder. for ccir mode operation with a pal composite or s-video output, use autoconfiguration mode 29 instead of autoconfiguration mode 28 and program the master device to send a digital fram e with an active re solution of 720x576. type of digital video i nput: interlaced 4:2:2 ycrcb active resolution (horizontalxvertical): 720 pixels x 480 lines overscan compensation: none. horizontal = 0%; vertical = 0% interface: CX25870/871 is clock and timing slave pixel rate 27.000 mhz type of analog video output: standard ntsc[ntsc-m]
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-66 conexant 100381b 1.3.39 ccir601 mode o peration for dvd playback data coming from a dvd is decoded by a mpeg2 decoder or graphics controller into a format called ccir601. ccir60 1 is the more common name for 4:2:2 ycrcb data at a 27 mhz pixel rate, as specified in the itu-r bt.601 standard. this specification was developed specifical ly for the digitalization of color video signals. to play a dvd movie on a television in addition to a crt monitor, the CX25870/871, a ccir601 compatible enco der, must be integrated into the hardware design. actual ccir601 data must be sent from a mpeg2 decoding master device directly to the cx2587 0/871 encoder. this can be either a dedicated mpeg2 decoder chip or a graphi cs controller with this functionality. various software steps are necessary so the encoder enters slave or master interface and is set up to accept the inte rlaced ycrcb data or noninterlaced rgb digital format. after all of these steps have been executed properly, a dvd movie stream is properly encoded and rendered onto the television by the vga encoder. there are different capabilities among graphics controllers, mpeg2 decoders, and proprietary asics that impact the particular dvd implementation. this section seeks to cover all the possible ha rdware/software conf igurations and the trade-offs associated with each. if th e reader has an interface idea about the routing of data from the ccir601 source to encoder that is not discussed here, please contact your local conexant field applications engineer for further technical support. 1.3.39.1 ccir601 data in/ntsc out the first option to playing a dvd movie via the CX25870/871 is to send the digital video ccir601 data directly to the encoder from the mpeg2 decoder. in this case, the graphics controller does no t have any effect on the ccir601 digital stream arriving at the input of the encoder because it bypassed the data or the data was routed around the cont roller. in either case, the CX25870/871 must be configured to accept interl aced 4:2:2 ycrcb data with an active resolution of 720x480 and output a standard ntsc video output. the pertinent set of conditions for this option are: given this set of conditions, autoconfigur ation mode 28 is a perfect fit for this architectural option. as a result, simply use the mpeg2 decoders serial bus mastering ability to program the CX25870/871s config[5:0] field with a binary value of 011100. this translates into writing a hexadecimal number of 0x34 to register 0xb8. once the encoder acknowledg es this write to it s autoconfiguration register, it automatically loads the appropriate value for this type of dvd configuration into its register indices from 0x76 to 0xb4 including 0x38. the exact data transferred into th ese registers is contained in appendix c . type of digital video i nput: interlaced 4:2:2 ycrcb active resolution (horizontalxvertical): 720 pixels x 480 lines overscan compensation: none. horizontal = 0%; vertical = 0% interface: CX25870/871 is clock and timing slave pixel rate 27.000 mhz type of analog video output: standard ntsc[ntsc-m]
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-67 after completion of the autoconfigur ation command, the encoder expects to receive interlaced ccir601 data from the clock and timing master device at a rate of 27.000 mhz. if this occurs, approximately 40 clocks later (i.e., pipeline delay), the encoder begins transmitting a ntsc-compatible s-video or composite video signal containing the dvd movie. 1.3.39.2 ccir601 data in/pal out the second option is very similar to the first. in this scenario, the interlaced ccir601 video data is transmitted directly to the encoder from the mpeg2 decoder. however, instead of generating a ntsc signal, the encoder produces a pal-bdghi compatible dvd movie output. the active resolution changes as well for this alternative by increasing to 720x576. to enable dvd playback in this scenario, the CX25870/871 must be configured to accept interl aced 4:2:2 ycrcb data with an active resolution of 720x576 and output a standard pal video output. the pertinent set of conditions for this option are: given this set of conditions, autoconfigur ation mode 29 is a perfect fit for this architectural option. as a result, simply use the mp eg2 decoder?s serial bus mastering ability to program the CX25870/871s config[5:0] field with a binary value of 011101. this translates into writing a hexadecimal number of 0x35 to register 0xb8. once the encoder acknowledg es this write to it s autoconfiguration register, it automatically loads the appropriate value for this type of dvd configuration into its register indices from 0x76 to 0xb4 including 0x38. the exact data transferred into th ese registers is contained in appendix c . after completion of the autoconfigur ation command, the encoder expects to receive interlaced ccir601 data from the clock and timing master device at a rate of 27.000 mhz. if this occurs, approximately 40 clocks later (i.e., pipeline delay), the encoder will begin transmitting a pa l-compliant s-video or composite video signal containing the dvd movie. 1.3.39.3 vga- compatible rgb data in/ntsc out the third option for dvd playback is unli ke the previous two methods. in this case, the mpeg2 decoder?s 4:2:2 ycrcb interl aced data is sent as an input to the graphics controller. in turn , the controller deinterlaces and color space converts the ccir601 data into a noninterlaced rgb format. the encoder finally ends up receiving this standard vga digital data from the graphics controllers digital output port for generation into an analog tv signal. type of digital video input: interlaced, 4:2:2 ycrcb active resolution (horizontalxvertical ): 720 pixels x 576 lines overscan compensation: none. horizontal = 0%; vertical = 0% interface: CX25870/871 is clock and timing slave pixel rate 27.000 mhz type of analog video output: standard pal[pal-bdghi]
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-68 conexant 100381b this design is illustrated in figure 1-33 . to enable dvd playback with this arch itecture, the graphics controller must be able to deinterlace and color space convert the ccir601 input data from the mpeg2 decoding source. furthermore, since the pixel clock frequency is not 27.000 mhz any longer, the graphics controller must have the ability to synchronize the pixel data to the clock rate dictated by the CX25870/871s clko signal. finally, the controller must be able to function as the clocking master and timing slave as described in section 1.3.7 of this data sheet. the recommended interface for the cx25 870/871 for this option is master and the encoder must be programmed to accept noninterlaced rgb data and output a standard ntsc video output. the pertinent factors for this option are: given this set of conditions, autoconfigur ation mode 44 is a perfect fit for this architectural option. as a re sult, simply use the graphics accelerator?s serial bus mastering ability to program the CX25870/871s config[5:0] field with a binary value of 101100. this translates into writing a hexadecimal number of 0x54 to register 0xb8. once the encoder acknowledg es this write to it s autoconfiguration register, it automatically loads the appropriate values for this type of dvd configuration into its register indices from 0x76 to 0xb4 including 0x38. the exact data transferred into th ese registers is contained in appendix c . figure 1-33. dvd playback utilizing graphics controller for color-space and progressive scan conversion crt monitor 100381_061 dvd-rom drive 10 mbit/s 15 mbit/s 100 kbit/s 450 kbit/s speakers ntsc or pal television 20 mbit/s host adapter stream parsing graphics accelerator sound card CX25870/ cx25871 subpicture decoder mpeg-2 decoder ac-3 decoder type of digital video input: progr essive scan/noninterlaced; 24-bit rgb per pixel multiplexed input format active resolution (h orizontalxvertical): 720x480 overscan compensation ratio: minimal; horizontal = 1.24%; vertical = 1.23% interface: CX25870/871 is clock and timing master pixel rate 27.6923 mhz type of analog video output: standard ntsc[ntsc-m]
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-69 after completion of the autoconfig uration command, the encoder enters master interface. in addition, the cx25 870/871 will expect to receive digital frames with an active resolution of 720x480 comprised of noninterlaced rgb data at a pixel rate of 27.6923 mhz. if these events occur, approximately 40 clocks later (i.e., pipeline delay), the encoder will begin transmitting a ntsc-compliant s-video or composite vi deo signal containing the dvd movie. 1.3.40 secam output unlike its predecessor, the bt868/869, the CX25870/871 now includes an encoder block for conversion of digital video data into a secam composite (cvbs) and/or a secam s-video signal. like other video outputs, any active resolution from 320x200 to 1024x768 can be supported with the secam encoder bl ock. the circuit accepts rgb or ycrcb data in a variety of multiplexed or n onmultiplexed input form ats, reformats the digital data, and finally routes th e stream through the four on-chip digital-to-analog converters (dacs). the encoder supports all variations of the secam analog video standard includ ing those commonly used in france (secam-l), eastern europe/russia (d, k, k1), and greece/middle east (b, g, h). the secam specific processing is achieved in this block by a pre-emphasis of the color difference signals. once data is received, it is converted to an internal yuv format. next, the y component is filt ered and then upsampled to the system clock frequency while the uv components are used to frequency modulate the two subcarrier frequencies appropriately. the luminance signal is always low-pa ss filtered using the upsampling filter response illustrated in figure 1-24 . additional peaking or reduction filters can be enabled (see figures 1-25 through 1-27 ), using the pkfil_sel[1:0] bit field. the peaking filters are optimized for a high bandwidth frequency response and optimal picture quality. the default chrominance filter response is illustrated in figure 1-28 , but an alternate wide bandwidth response can be selected by setting register bit chroma_bw, as illustrated in figure 1-29 . the color subcarrier frequencies, 4.25000 mhz for db and 4.40625 mhz for dr, are controlled by a number of registers, chiefly ms c_db[31:0] for db an d msc[31:0] for dr. figure 1-30 illustrates the secam pre-emphasis fi lter response at higher (>3 mhz) frequencies within th e standard definition television passband. table 1-21 lists three complete register sets for the most common desktop input resolutions w ith the secam output. this ou tput adheres to the secam target video parameters included in table a-1 . this occurs only if the conexant encoder is programmed correctly w ith the register values listed in table 1-21 , the master device provides the rgb data at the listed clock frequency (clki/clko), and the interface bits are modified to match the desired connection type.
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-70 conexant 100381b table 1-21. register values for 640x480 / 800x600 / 1024x768 rgb in, secam-l out (1 of 4) 640x480 rgb in, secam-l out hoc = 16.55%, voc = 16.66% 800x600 rgb in, secam-l out hoc = 14.52% voc=13.19% 1024x768 rgb in, secam-l out hoc = 12.72% voc = 12.15% clki/clko frequency 29.500007 mhz 36.000000 mhz 67.687489 mhz state of pll_32clk bit 0 0 1 internal pixel clock frequenc y 29.500007 mhz 36.000000 mhz 45.124993 mhz register address CX25870 register values CX25870 register values CX25870 register values 0x00 00 00 00 0x02 00 00 00 0x04 00 00 00 0x06 00 00 00 0x2e 00 00 00 0x30 00 00 00 0x32 00 00 00 0x34 00 00 00 0x36 00 00 00 0x38 00 00 20 0x3a 00 00 00 0x3c 80 80 80 0x3e 80 80 80 0x40 80 80 80 0x42 (5) 8b 8e 9b 0x44 (5) a0 e3 5d 0x46 (5) e1 38 1c 0x48 (5) 24 1e 18 0x4a (5) 28 3a 5f 0x4c (5) 3b 77 c4 0x4e (5) 25 1c 13 0x50 (5) 28 3a 5f 0x52 (5) 3b 77 c4 0x54 (5) 25 1c 13
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-71 register address CX25870 register values CX25870 register values CX25870 register values 0x56 (5) ac 18 7a 0x58 (5) 20 27 31 0x5a 00 00 00 0x5c 00 00 00 0x5e 00 00 00 0x60 00 00 00 0x62 00 00 00 0x64 00 00 00 0x66 3c e3 d9 0x68 00 00 00 0x6a 00 00 00 0x6c (1) 46 46 46 0x6e 00 00 00 0x70 0f 0f 0f 0x72 00 00 00 0x74 01 01 01 0x76 60 00 48 0x78 80 20 00 0x7a 8a aa d4 0x7c a6 ca fc 0x7e 68 9a e2 0x80 c1 0d 79 0x82 2e 29 28 0x84 f2 fc fe 0x86 27 39 4b 0x88 00 00 00 0x8a b0 c0 91 0x8c 0a 8c 5e 0x8e 0b 03 0d 0x90 71 ee b6 table 1-21. register values for 640x480 / 800x600 / 1024x768 rgb in, secam-l out (2 of 4) 640x480 rgb in, secam-l out hoc = 16.55%, voc = 16.66% 800x600 rgb in, secam-l out hoc = 14.52% voc=13.19% 1024x768 rgb in, secam-l out hoc = 12.72% voc = 12.15%
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-72 conexant 100381b register address CX25870 register values CX25870 register values CX25870 register values 0x92 5a 5f 76 0x94 e0 58 00 0x96 06 0a 3f 0x98 00 66 a4 0x9a 50 96 a0 0x9c 72 0 55 0x9e 1c 0 15 0xa0 0d 10 1e 0xa2 8c 8c 24 0xa4 f0 f0 f0 0xa6 58 57 56 0xa8 (5) 76 5f 4b 0xaa (5) 4d 3e 31 0xac 8c 8c 8c 0xae (5) ea 55 76 0xb0 (5) be 55 4a 0xb2 (5) 3c 55 ff 0xb4 (5) 26 1f 18 0xb6 00 0 0 0xb8 01 3 33 0xba 00 0 0 0xbc 00 0 0 0xbe 00 0 0 0xc0 00 0 0 0xc2 00 0 0 0xc4 (2) 01 1 1 0xc6 (3) 03 3 3 0xc8 1b 1b 1b table 1-21. register values for 640x480 / 800x600 / 1024x768 rgb in, secam-l out (3 of 4) 640x480 rgb in, secam-l out hoc = 16.55%, voc = 16.66% 800x600 rgb in, secam-l out hoc = 14.52% voc=13.19% 1024x768 rgb in, secam-l out hoc = 12.72% voc = 12.15%
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-73 the procedure required to obtain a secam output with an overscan compensation percentage that di ffers from those solutions in table 1-21 is fairly simple. first, configure the encoder so it generates a standard pal-b output with the desired overscan compensation percenta ge. this can be done through the use of an autoconfiguration mode, a hand-generated, or a predefined register set. second, perform a full register read-bac k from the CX25870. carefully note the value for register 0xa2. third, program only the bits found in table 1-22 to their new state within the CX25870. register address CX25870 register values CX25870 register values CX25870 register values 0xca c0 c0 c0 0xcc c0 c0 c0 0xce (4) 24 24 24 0xd0 00 0 0 0xd2 00 0 0 0xd4 00 0 0 0xd6 00 0 0 0xd8 40 40 40 note(s): 1. register 0x6c contains the timing_reset bit. set this bit as your la st programming step and the CX25870 will clear it automatically later. 2. register 0xc4 contains the en_out bit. adjust according to your design's interface as necessary. 3. register 0xc6 contains the en_blanko, en_dot, and in_m ode[2:0] bits. adjust according to your design's interface as necessary. 4. register 0xce contains th e out_muxd[1:0], outmuxc[1:0], outmuxb[1:0], and outmuxa[1: 0] bit fields for output routing. adjust according to your design's interface as necessary. 5. this is a secam specific register. table 1-21. register values for 640x480 / 800x600 / 1024x768 rgb in, secam-l out (4 of 4) 640x480 rgb in, secam-l out hoc = 16.55%, voc = 16.66% 800x600 rgb in, secam-l out hoc = 14.52% voc=13.19% 1024x768 rgb in, secam-l out hoc = 12.72% voc = 12.15% table 1-22. vital secam bit settings?register 0xa2 bit name location state for pal-bdghi state for secam fm bit 7 of register 0xa2 0 1 pal_md bit 5 of register 0xa2 1 0 vsync_dur bit 3 of register 0xa2 0 0
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-74 conexant 100381b finally, calculate the values for th e msc_db[31:0], mcr[7:0], mcb[7:0], filfsconv[5:0], fil4286incr[7:0], and msc[31:0] registers for the particular secam overscan solution. to accomplish th is task, read back both values that comprise the hclko[11:0] register, convert it to decimal (base 10), and use it in the equations below. after solving each secam register equation, perform a conversion back to a hexadecimal number and program the appropriate registers with their new secam specific values. the equations for generation of a secam output based on a rgb input only are: msc_db[31:0] = int ((272 / h_clko[11:0]) * 2 32 + 0.5) dr_limitp[10:0] = ((4.756 mhz/ inte rnal pixel clock frequency)*2^13) dr_limitn[10:0] = ((3.9 mhz/ internal pixel clock frequency)*2^13) db_limitp[10:0] = ((4.756 mhz/ inte rnal pixel clock frequency)*2^13) db_limitn[10:0] = ((3.9 mhz/ internal pixel clock frequency)*2^13) if pll_clk32 is 0, then internal pixel clock frequency = clki = clko. if pll_clk32 is 1(for some overscan ratios in 800x600 and all 1024x768 resolutions), then internal pixel clock frequency = (2/3) * clki fil4286incr[7:0]: six equations required to find hex value scincr_off = int(8192 * 4.286 * 1728 / (27 * h_clko[11:0]) + 0.5) scincr_offh = dec2hex(scincr_off) scincr_offb = hex2bin(scincr_offh) scincr_intb = scincr_offb &( bitwise and operator) with 111111111(binary) scincr_intnot = not[scincr_intb] fil4286incr[7:0] = [bin2dec {scincr_intnot}] 2 filfsconv[5:0] = int((27 * h_clko[11:0] * 1.087) / 1728 + 0.5) for rgb input only: mcr[7:0] = int ((920.26) / (288036.0 * h_clko[11:0] * sinx) * 2 26 + 0.5) where sinx = [sin (p * fsc / clki)] / (p * fsc / clki) mcb[7:0] = int ((598.15) / (288036.0 * h_clko[11:0] * sinx) * 2 26 + 0.5) where sinx = [sin (p * fsc / clki)] / (p * fsc / clki) msc[31:0] = int ((282 / h_clko[11:0]) * 2 32 + 0.5) my = same as pal, no change required for secam for ycrcb input only: mcr[7:0] = int (1.902/(224*0.713)*(0.28/fclk)/(84*sinx)*2 27 +0.5) mcb[7:0] = int (1.505/(224*0.564)*(0.28/fclk)/(84*sinx)*2 27 +0.5) my = same as pal, no change required for secam
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-75 1.3.41 macrovisi on copy protection the cx25871 device supports version 7.1.l1 of the macrovision specification for copy protection for all ntsc, pal, and secam video outputs. the CX25870 does not support the macrov ision feature whatsoever. note: the cx25871 will power-up with macrovision copy protection enabled as required by macrovision version 7.1.l1. for detailed instructions and lists of de fault register values for the cx25871 obtain a macrovision license and then ask for the macrovision process supplement application note from your local conexant salesperson or field application engineer. table 1-23. secam specific registers register address description value for pal-bdghi value for secam 0x42 msc_db[7:0] not used for pal- bdghi use msc_db [31:0] equation 0x44 msc_db[15:8] not used for pal- bdghi use msc_db [31:0] equation 0x46 msc_db[23:16] not used for pal- bdghi use msc_db [31:0] equation 0x48 msc_db[31:24] not used for pal- bdghi use msc_db [31:0] equation 0x4a dr_limitp[7:0] not used for pal- bdghi use dr_limitp [10:0] equation 0x4c dr_limitn[7:0] not used fo r pal-bdghi use dr_limitn[10:0] equation 0x4e dr_limitn[10:8] & dr_limitp[10:8] not used for pal-bdghi use dr_limitn[10:0] equation use dr_limitp[ 10:0] equation 0x50 db_limitp[7:0] not used for pal-bdghi use db_limitp[10:0] equation 0x52 db_limitn[7:0] not used for pal-bdghi use db_limitn[10:0] equation 0x54 db_limitn[10:8] & db_limitp[10:8] not used for pal-bdghi use db_limitn[10:0] equation use db_limitp[10:0] equation 0x56 fil4286incr[7:0] not used for pal- bdghi use fil4286inc r[7:0] equation 0x58 bits 5-0 are filfsconv[5:0] not used for pal-bdghi use filfsconv[5:0] equation 0xa8 mcr[7:0] overscan ratio dependent use mcr[7:0] equation 0xaa mcb[7:0] overscan ratio de pendent use mcb[7:0] equation 0xae msc[7:0] overscan ratio de pendent use msc[31:0] equation 0xb0 msc[15:8] overscan ratio de pendent use msc[31:0] equation 0xb2 msc[23:16] overscan ratio de pendent use msc[31:0] equation 0xb4 msc[31:24] overscan ratio de pendent use msc[31:0] equation
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-76 conexant 100381b 1.3.42 hdtv output mode the CX25870/871 includes an hdtv outp ut mode that generates the analog rgb or analog yp b p r component video outputs necessary for driving an hdtv?s hd input port. while generating hdtv outputs, the device accepts rgb or yp r p b digital data in a 480p, 720p, or 1080i atsc reso lution. after a pipeline delay, it outputs either analog rgb or analog yp b p r signals and automatically inserts trilevel synchronization pulses (when necessary) and vertical synchronizing ?broad pulses?. the output waveforms, input data requirements and all configuration details are explained in appendix e . the device complies with all major smpte and eia standards governing the hdtv resolutions. 1.3.43 scart output in this mode of operation, the CX25870/871 can be used successfully to provide one full red/green/blue/composite (or optionally, a 2-signal luminance and chrominance) scart/peritel output to drive scart-compatible televisions or vcrs. many pal/european tvs being manufactured now have scart compatible sockets, that allows the televi sion and the set top box, graphics card, or game console driving it to work in rgb color instead of the standard composite. the picture quality for full sc art is significantly better due to the individual rgb composite signals being sent directly to the tv color guns. this is opposed to the tv having to modulate and decode the rgb signals from another color format. this ultima tely yields a crisper picture. on power-up, the CX25870/871 will output ntsc or pal standard-definition television outputs depending on the state of the pal pin. to switch the device into scart output mode with three sync-les s red/green/blue (r gb) analog outputs and a single composite (cvbs) pal video output from the fourth dac, program the encoder into a satisfactory pal outp ut mode and then perform the sequence of serial writes found in table 1-24 .
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-77 note: no change to the incoming or outgoing hsync* and vsync* signal frequencies are necessary for scart generation. the sync rates should continue to match those found with pal-bdghi transmission. while the CX25870/871 is in scart outmode, the composite video output (video[3]) contains a standard bilevel analog sync along with all other components that comprise a standard pal-bdghi video signal. the sync pulse has an amplitude of 0 mv to 300 mv peak-to-peak and a duration of 4.70 s by default. the amplitude can only be adjusted through the use of external passives, but its width can be adjusted through serial writing of the CX25870 hsync_width register. the CX25870?s composite should be us ed by the subsystem to provide the positive-going video output/sync output expected by scart-compliant display devices. in other words, the pal composit e output should be fed into the video input (contact #20-cei iec 933-1) on the scart connector. cvbs will possess the same bandwidth and time delays as the CX25870 rgb primary color signals. the inclusion of a full composite video signal as the 4 th output exceeds the scart capabilities of some non-conexant flicker filter encoders which choose to output only composite sync as the 4 th output. this implementation benefits the customer because some european set-top boxes connect to tvs solely through the scart connector. if the tv only receives composite video via the scart connector, and the set top box is set to rgb output with sync for blanking (not cvbs) on pin 20, a picture will not be present at all on the tv. however, with the CX25870, if the tv only receives cvbs (not rgb) and the set top box is set to rgb output with cvbs on pin 20 the customer will get a colorful picture on his tv. table 1-24. serial writes required to sw itch CX25870/871 into scart output operation bit name location value comment en_scart bit 3?register 0x6c 1 enabl es scart output mode . dacs will transmit video[0-3] as scart compatible rgb/cvbs outputs. by default, in scart output mode, the CX25870 will transmit: dac_a = video[0] = red dac_b = video[1] = green dac_c = video[2] = blue dac_d = video[3] = pal composite (cvbs) out_muxd[1:0] out_muxc[1:0] out_muxb[1:0] out_muxa[1:0] bits 7:0?register ce e4 by configuring th e dac routing register , the CX25870 will now transmit: dac_a = video[0] = 00 = red dac_b = video[1] = 01 = green dac_c = video[2] = 10 = blue dac_d = video[3] = 11 = pal composite (cvbs) out_mode[1:0] bits 3: 2?register d6 11 forces CX25870 to generate scart output mode.
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-78 conexant 100381b the rgb primary color signals generated in scart mode will not contain any embedded syncs. for each output, the difference between the peak value (pure white) and blanking level is 0.7 v ( 3 db). therefore, the blanking level will reside at gnd (0 mv) and the ma ximum level is 700 mv for rgb. the hsync* and vsync* digital inputs received by the CX25870/871 continue to act as a trigger to start a new line and new frame respectively as is the case with composite and svhs outputs. the rgb si gnals are blanked in accordance with the values contained in the h_blank o and v_blanko registers, with h_clko and h_active playing a lesser role. the primary color signals expect a 75 ? load from the display device. correct rgb amplitudes are generated when the CX25870?s scart outputs each ?see? an equivalent impedance of 37.5 ? between the source and destination. by default, the rgb positive-going signals are transmitted from the CX25870 in the following manner: note: video[0-3] can be routed out of any of the 4 on-chip dacs by adjusting the appropriate out_m uxa/b/c/d[1:0] bits. other major characteristics of the CX25870/871 scart output mode are: acceptable digital rgb inputs include 24/16/or 15 bits per pixel multiplexed or nonmultiplexed, noninterlaced rgb. acceptable digital ycrcb inputs include 24/16 bits per pixel multiplexed or nonmultiplexed, noninterlaced ycrcb. CX25870 can operate in master, ps eudo-master, or slave interface. pixel sampling rate in this mode is determined based on the incoming and outgoing clock frequencies (clki and clko). dac resolution for all dacs = 10-bits. red/green/blue/composite scart output from CX25870/871 limited to a max active resolution of 800 x 600. y/c scart output ok to a maximum active resolution of 1024 x 768. compliance with the eu ropean en50-049 scar t connector standard. blue should be received as pin #7, green as pin #11, red as pin #15, and cvbs out from the CX25870 as composite out at pin #19 (display side of connector). compliance with the cei iec publication 933-1 standard. blue should be received as pin #7, green as pin #11, red as pin #15, and cvbs out from the CX25870 as composite out at pin #19 (display side of connector). the CX25870 is compliant with the ma jor standards and technical reports governing the scart interface. table 1-26 summarizes the pins to be used for transmission of scart rgb/cvbs video with this conexant device. table 1-25. default scart outgoing signal assignments pin # on CX25870/871 scart output 68 = daca video[0] = red primary color 70 = dacb video[1] = green primary color 72 = dacc video[2] = blue primary color 66 = dacd video[3] = pal-bdghi composite
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-79 a specialized cable and connector are required to connect the CX25870?s rgb/cvbs or y/c outputs to the tv?s sc art input. this cable can be procured from various european electronic stores and comes in at least two different arrangements. consult the cei iec 933-1 specification ( audio, video, and audiovisual systems-interconnections and matching values ) for a precise illustration of their 21-contact scart co nnector, video signal peak-peak values, and cordset types. the most common types of scart connec tors are the so-called type i and ty p e i i va r i e t y. figures 1-34 and 1-35 illustrate the recommended type i and type ii scart connector pinout arrangements. table 1-26. CX25870 scart outputs for different scart standards rgb standard red green blue composite/blanking european en50-049 scart (1) connector pin 15 pin 11 pin 7 pin 19 -composite out (to display) cei iec 933-1 : (1) bbc scart arrangement #1 pin 15 pin 11 pin 7 pin 19 - composite out (to display) y- c standard chroma x luma x luminance - chrominance (2) scart: bbc scart arrangement #2 pin 15 c pin 20 ? note(s): (1) red/green/blue signals levels are fr om 0 v + 0.7 v peak-to-peak with 75 ? load impedance. (2) the luminance ? chrominance outputs for scart are equivalent to pal-bdghi s-vi deo. therefore, outmode[1:0] should be programmed to 00, the en_scart bit s hould be reset to 0, and the outmuxa/b/ c/d[1:0] bits adjusted according to which dacs must transmit luminance( video[1]) and chrominance(video[2]). figure 1-34. CX25870 driving a type i scart connector (en 50-049 and iec 933-1 compliant) 100381_092 cvbs as sync y/r c/g 3.3 v 3.3 v 3.3 v +3.3 v 3.3 v 21 19 17 15 13 11 9 7 5 3 1 20 18 16 14 12 10 8 6 4 2 cvbs/b CX25870/871 std def lpf scart connector std def lpf std def lpf std def lpf 75 ? 1% 75 ? 1% 75 ? 1% 75 ? 1%
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-80 conexant 100381b conexant recommends that any designer utilizing the CX25870 with either type of scart output utilize the same dac low-pass filters used for standard definition tv outputs listed in chapter 3.0 of this data sheet. 1.3.44 interlaced standard definition analog component video tv outputs in this mode of operation, the CX25870/25871 provides a set of component video y, pb (b?y), pr (r?y) outputs based on a 480 line interlaced rgb or ycrcb digital input format. some dvd play ers, such as those made by toshiba and panasonic, call the component video output format by their branded name, ?colorstream.? others re fer to the two eia standards governing this video format?eia-770.1 and eia-770.2-a, and state this video type as interlaced component video, 480i component video, or component yuv. regardless of the different names, the video format remains the same. for instructions on how to configure the CX25870/871 to generate progressive 480p component video (or colorstream pro), refer to that particular section in this data sheet. the designer can enable colorstream by using three of the CX25870?s dacs to generate two color difference signals (p r and p b sometimes referred to as c r and c b ) and a single luminance signal (y). these three channels allow the video generating device to bypass the tv?s in ternal y/c separator and color decoder circuits. the analog information therefor e gets routed directly into the tv?s matrix decoder. by sending the pure component video signal directly to a component video or colorstream input-equi pped display media, the input signal forgoes the extra processing that normally would degrade the analog image. figure 1-35. CX25870 driving a type ii scart connector (y/c and bbc scart compliant) 100381_093 y/r c/g 3.3 v +3.3 v 3.3 v 21 19 17 15 13 11 9 7 5 3 1 20 18 16 14 12 10 8 6 4 2 cvbs/b CX25870/871 scart connector std def lpf std def lpf 75 ? 1% 75 ? 1%
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-81 the advantage of this type of video is increased image qual ity combined with more lifelike colors and crisper detail. because the video information is transferred over three separate connecting cables instead of two (for s-video) or one (for coaxial or rca/composite), 480i component video yields the best standard definition tv quality available. however, because we are still dealing with standard 480 line interlaced resoluti ons, this format remains inferior to high-definition tv. output devices used for generating this format include, but are not limited to, digital tv set top boxes, satellite db s receiver decoders, and dvd players. input media capable of decoding colorstr eam include television receivers and/or monitors. while in the component video mode, all 10-bits of the CX25870?s d/a converters are available for encoding. th is results in a d/a conversion more accurate than conventional 8-bit, 13.500 mhz systems. the end result is a more artifact-free and clear image. some major characteristics governing the interlaced standard definition television analog component video interface are as follows: the digital input stream can be received in a progressive (i.e., noninterlaced) format or interlaced format. interlaced data must be transmitted as odd?even?odd ? fields. the fields carry every other scan line in succession with succeed ing fields carrying the lines not scanned by the previous field. each field will be divided into an active picture area and a vertical blanking interval (vbi). similarly, each line will be divided into an active pixel area and a horizont al blanking interval. the 480i video output will be capable of either a 4:3 or 16:9 aspect ratio through embedding of wide screen signaling (wss) bits into the appropriate lines in the vbi. review the section 1.3.35 in the data sheet for more details. if configured properly, the CX25870?s eia 770.2-a compliant component video luminance signal has a peak amplitude of 700 mv from the blanking level, with zero setup. a negative-going bilevel sync pulse of 300 mv, conforming to the timing requirements in figure 1.3-a, is added to the luma signal as the only timing reference fo r the complete y p r p b set of signals. neither p r nor p b will contain an embedded sy nc pulse. both will have a maximum peak amplitude of 350 mv. the dc level of p r and p b during the horizontal line shown in figure 1-36 below will be at reference black with a voltage of 0 v. it will be generated in conformance with the eia 770.2-a and eia770.1 standards. the only differences between these standards are the presence of the 7.5 ire setup pedestal and slightly different luminance levels. check tables 1-27 and 1-28 for complete programming instructions for either standard. pixels per active line active lines per frame frame rate (hz) output scanning format total samples per line total liens per frame 720 480 30 / 1.001 interlaced 858 525
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-82 conexant 100381b the three component video signals y, p b , and p r will be coincident with respect to each other within 5.0 ns. any filtering that introduces group delay exceeding 5.0 ns should be redesigned. to switch the device into 480i comp onent video output mode with bilevel syncs embedded into each of the three yp r p b analog outputs, first, program up the CX25870/871 into a fully functional ntsc over-scan solution where composite and/or s-video is being generate d out of at least three of the encoder?s outputs. next, change the registers found in table 1-27 to the indicated values. figure 1-36. yp r p b component video signals using 100/0/100/0 color bars as the digital input signal (courtesy? eia-770.2-a standard, page 8 and eia-770.1 standard) 100381_098 clamp period y pb pr sync period wht yel cyn grn mgt red blu blk eia770.1 eia770.2-a eia770.1 eia770.2-a eia770.1 eia770.2-a +714 +700 +350 +350 +350 +350 00 00 00 ?286 ?300 ?350 ?350 ?350 ?350
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-83 for eia-770.1 compliant component video out, no other programming steps are required for the CX25870/871 beyond table 1-27 . for the more common eia-770.2-a compliant component video out, a few additional programming steps are required. these are listed in table 1-28 below: table 1-27. common registers required to switch CX25870/25871 into eia-770.2-a- or eia-770.1-compliant component video outputs register/bit name location value comment mcompy[7:0] bits 7:0 ? register 3c 80 (hex) gai n multiplication factor for y analog output. mcompu[7:0] bits 7:0 ? register 3e 90 (h ex) gain multiplica tion factor for p b analog output. mcompv[7:0] bits 7:0 ? register 40 66 (h ex) gain multiplica tion factor for p r analog output. setup bit 1 - register a2 1 (binary) require d for eia770.1 complian ce. enables 7.5 ire pedestal normally present wi thin ntsc-m active video lines. out_mode[1:0] bits 3:2 - register d6 10 (binary) enables component video output mode. CX25870 dacs will transmit video[0-3] as eia-770.2-a or 770.1 compliant p r / y / p b / y_delay outputs. out_muxa[1:0] out_muxb[1:0] out_muxc[1:0] out_muxd[1:0] bits 1:0 - register ce bits 3:2 - register ce bits 5:4 - register ce bits 7:6 - register ce 00 (binary) 01 (binary) 10 (binary) 11 (binary) by default, in component video output mode, the CX25870 will transmit: dac_a = video[0] = p r = v dac_b = video[1] = y dac_c = video[2] = p b = u dac_d = video[3] = y_delay table 1-28. unique registers required to switch CX25870/ 25871 into eia-770.2-a- compliant component video outputs register/bit name location value comment setup bit 1?register a2 0 (binary) required fo r eia770.2-a compliance. removes 7.5 ire pedestal normally present within ntsc-m active video lines. sync_amp[7:0] bits 7:0?register a4 f0 (hex) multip lication factor for adjusting the analog sync amplitude tip to ?300 mv for eia-770.2-a. my[7:0] bits 7:0?register ac 85 (h ex) additional gain multiplication factor for y eia-770.2-a analog output. this register needs to be increased by 6 percent of its nominal value. for a ntsc output based on a rgb digital input, this register would be increased 6 percent to 8c (hex) from a nominal value of 85 (hex).
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-84 conexant 100381b the analog y, pb, and pr - video[0-3] outputs can be routed out of any of the four on-chip dacs by adjusting the appropriate out_muxa /b/c/d[1:0] bits. all of the out_mux bits are contained in register 0xce. because the CX25870 device has four dacs and only three are needed for component video, the designer can choose to use the 4 th output, usually from dac_d, for any purpose deemed necessary. this output can be configured to either the p r , y, p b, or y_delay output via out_muxd. if the output is not going to be used whatsoever, conexant recommends dac_d be disabled by setting dacdisd (bit 3, register ba). this will save on power dissipation. the component video output signals expect a 75 ? load to ground from the display medium. correct y, p r , p b amplitudes will be generated only when each CX25870 output sees an equivalent impedance of 37.5 ? between the source and destination. the CX25870 is compliant with the ma jor standards and technical reports governing the standard definition tv analog component video interface. the name of these standards are as follows: eia 770.2-a?standard definition tv analog component video interface eia 770.1?standard definition tv analog component video interface ansi/smpte standard 170m (1994) (m/ntsc) for television?composite analog video signal?ntsc for studio applications to obtain any of these specifications, visit global engineering documents at: http://global.ihs.com/ conexant recommends that any designer utilizing the CX25870 with a component video output utilize the same dac low-pass filters used for standard definition tv outputs listed in figure 3-2 of this data sheet.
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-85 1.3.45 vga(rgb)?d ac output operation in this mode of operation, the CX25870/871 acts as a general-purpose triple high-speed d/a converter used to drive vi deo receivers, such as pc monitors. the encoder accomplishes this by bypassing most of the encoder blocks utilized for television outputs, such as the flicker filter and fifo and routing the rgb or ycrcb digital data straight through to the on-chip 10-bit dacs. once the data arrives at the dacs, it is quickly converted to a set of 700 mv peak-to-peak analog outputs, streamed through the re spective dac_x output pins, and routed onto the rest of the graphics sy stem according to the pcb layout. optimal performance is achieved when the CX25870/871?s current controlled dacs are terminated into appropriate resi stive loads to produce voltage outputs. the chip?s dac outputs are specifically designed to produce video output levels with a total peak-peak active-region amplitude of 700 mv when directly connected to a single-ended, do ubly terminated (req = 37.5 ? ) load. with the recommended loading of two 75 ? 1 percent resistor s (one each for the transmitting and receiving side), the fu ll-scale video amplitude is from 286 mv (blanking) to 986 mv (maximum luminance) and synchronization pulses from 0 mv (negative sync tip) to 286 mv (blanking) respectively. the analog synchronization pulse is ge nerated by the CX25870/871 every time it receives a falling edge on either the hsync* or the vsync* input by default. these sync pulses can be disabled for the rgb outputs by following the steps found in table 1-30 . on power-up, the CX25870/871 will output ntsc or pal standard-definition television outputs depending on the state of the pal pin. to switch the device into vga-dac output mode with bilevel syncs embedded on every red/green/blue (rgb) analog output, perform the sequ ence of serial writes found in table 1-29 only. table 1-29. serial writes required to switc h CX25870/871 into vga/dac output operation bit name location value comment slaver bit 5?register 0xba 1 ensures cx25871 in slave or pseudo-master interface en_xclk bit 7?r egister 0xa0 1 clki used as pixel clock source. setup bit 1?r egister 0xa2 0 setup off. the +56 mv pedestal setup is disabled for active video lines. out_mode[1:0] bits 3:2?register d6 11 video [0-3] = 11 = vga output mode: dac_a = video[0] = red dac_b = video[1] = green dac_c = video[2] = blue dac_disd bit 3?register 0xba 1 disables dacd output . current is set to 0 ma. output voltage goes to 0 v.
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-86 conexant 100381b of course, the master device?s timi ng signals (hsync*, vsync*, clki) and the digital data sent to the CX25870/87 1 must also be adju sted to ensure the proper operation of this mode. some applications, such as vesa comp liant pc monitors, dictate that the embedded bilevel syncs be completely absent from the rgb analog outputs. fortunately, the CX25870/871 can provide vesa?s ?syncless? outputs so long as the additional set of bits found in table 1-30 are programmed as shown: complete all steps in tables 1-29 plus 1-30 . the outputs generated from the combined steps listed in table 1-29 and table 1-30 will not contain any embedded syncs, but will contain a positive 286 mv dc offset because the encoder cann ot generate negative voltage levels. therefore, the blanking level will resi de at 286 mv and the maximum luminance level is 986 mv for the 3 different outputs. the hsync* and vsync* digital inputs received by the CX25870/871 will co ntinue to cause blanking, but this is irrelevant since the data itself is blanked at these times. to reiterate, the vesa video signal st andard specification requires that the dac analog output stay between 0.0 vdc and 0.700 vdc +.07 v (or -.03 v) with no excursions at all times. clearly, th e blank and maximum luminance levels for the CX25870/871 are in violation of this specification. to compensate for the dc offset, the CX25870/871 is reliant on th e vga monitor?s decode capabilities to remove this dc deviation. through testing, conexant has determined that most, if not all, present-day monitors have this function to filter out minor dc offsets. other major characteristics of the CX25870/871 vga?dac output mode are: acceptable digital rgb inputs include 24/16/or 15 bits per pixel multiplexed or nonmultiplexed rgb acceptable digital ycrcb inputs include 24/16 bits per pixel multiplexed or nonmultiplexed ycrcb CX25870 can only be a slave to the da ta master in this type of operation sampling rate in this mode is dete rmined based on the incoming clock frequency (clki) dac resolution for all dacs = 10-bits table 1-30. serial writes required to remove bilevel syncs from all vga/dac outputs bit name location value comment hdtv_en bit 7?register 0x28 1 dacs output hdtv compatible rgb raster_sel[1:0] bits[1:0]?register 0x28 00 default state. no need to reprogram. rgb2prpb bit 6?r egister 0x28 0 default state. no need to reprogram. bpb_sync_dis bit 3?register 0x28 1 disables sync on blue output gy_sync_dis bit 4?register 0x28 1 disables sync on green output rpr_sync_dis bit 5?register 0x28 1 disables sync on red output note(s): when all bits in tables 1-29 and 1-30 are programmed correctly, th e active video level range will be from +286 mv to +986 mv.
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-87 finally, conexant recommends that any designer utilizing the CX25870 in this mode circumvent the three capacitors and one inductor found in the dac low-pass filters used for standard definition tv outputs. figure 1-37 illustrates one method of bypassing the capacitors an d inductor. note that an additional rca (or other type) of connector is recomme nded in this case for the red. green, and blue vga outputs. figure 1-37. filterless dac outputs for vga (rgb)?dac output operation 100381_083 68 CX25870/871 in vga output mode daca dacb dacc dac a cvbs = composite dac b dac c 70 72 vaa 3.3 v 1 1 2 2 3 3 1 2 3 d6 bat54s sot-23 5443r10-0041 r1 75.0 ? 0805 5% c9 270 pf 0805 5% c8 22 pf 0805 5% aout vga r output c10 330 pf 0805 5% l1 1.8 h 1210 5% dac b y = luma c = chroma vaa 3.3 v 1 1 2 2 3 3 1 2 3 d6 bat54s sot-23 5443r10-0041 r2 75.0 ? 0805 5% c13 270 pf 0805 5% c12 22 pf 0805 5% bout vga g output c14 330 pf 0805 5% l3 1.8 h 1210 5% dac b vaa 3.3 v 1 1 2 2 3 3 1 2 3 d6 bat54s sot-23 5443r10-0041 r7 75.0 ? 0805 5% c16 270 pf 0805 5% c15 22 pf 0805 5% cout vga b output c17 330 pf 0805 5% l2 1.8 h 1210 5% note(s): make sure to have only one of the paired outputs plugged in simultaneously.
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-88 conexant 100381b 1.3.46 tv auto-d etection procedures the device can determine whether or no t the dac output is connected to a monitor by verifying that the output is doubly-terminated. the monstatx bit for the corresponding dac is set to a 1 if the device senses a doubly-terminated load on a reset condition or if the check_stat register bit is set. while check_stat is set, the output is forced to 2/3 of vref when terminated and 4/3 of vref if unterminated. the monsta tx bit reflects the condition when the dac output is less than or equal to vref. the check_stat bit is automatically cleared after two clock cycles. the CX25870/871 can be read from using 2 different methods. the first method is called standard serial read-back. to perf orm a read, simply have the master device issue the CX25870/871?s serial device address (0x89 or 0x8b depending on the state of the encoders altaddr pin), transmit the particular subaddress (encoder register index) to read from, and then wait for the CX25870/871 to transmit the appropriate 8-bits of data. of course, start and stop conditions and acks must exist at the pertinent times as well, but this summarizes the basic procedure. the second method that can be used to read back fr om the encoder is called the legacy method. this is because the pro cedure that follows was the only manner in which conexant?s first genera tion encoder (i.e., bt868/869) could be read from. for compatibility purposes, this method was carried forward and exists in this second generation encoder. the legacy procedure to follow for serial re ad-back and tv detection purposes is: 1. write 01 to the estatus[1:0]{bits d7=msb and d6 of register 0xc4}bit field. this sets up the encoder to r ead the monstat data and check if the dacs have a tv connected. 2. write the check_stat register bit to a one (bit d6 of register ba). this will latch the monstat data inte rnally and then clear itself. 3. wait 600 s to allow the analog no des to reach their operating point. 4. read the monstat data by issuing 0x89 or 0x8b for the CX25870/871?s device address. this ensures the leas t significant bit of the device write portion of the transaction is 1, which indicates to the encoder that it must send a byte of data on the next serial transaction. do no t write a subaddress to the encoder (this is not necessary si nce the first generation encoder only had one read register) and then read th e next byte after the ack. the 8-bit read in step 1 contains either the CX25870?s id&version (if estatus was written to 00) or the CX25870?s monitor detection for dacs c, b, and a + closed caption status info and the field # (if estatus = 01). if estatus was written to 10 in step 1, the read byte will contain the pll_lock, fifo status bits , pal bit, and busy bit.
CX25870/871 1.0 functional description flicker-free video encoder with ultrascale technology 1.3 device description 100381b conexant 1-89 table 1-31 summarizes the meaning of the read-back bits wh en the agency procedure is used and estatus[1:0] = 10, 01, or 00. 5. if estatus = 01, the serial master shou ld receive one byte of information telling it the following in formation in this order: a. monitor connection status for daca output (monstat_a = most significant bit). b. monitor connection status for dacb output (monstat_b). c. monitor connection status for dacc output (monstat_c). d. ccstat_e, ccstat_o. e. field2, field1, field0 (least sign ificant bit). the field[2:0] bits indicate the field number that was last encoded. 000 indicates the 1st field. 6. the serial master must issue a st op condition to finish the read transaction. an ack is not necessa ry before closing the transaction because the CX25870 just ignores the ack anyway. in reality, the CX25870/871 does not really care abou t ending a transaction properly as long as a proper start condition is us ed to start the next transaction. in the read mode when the CX25870 is driving the sda port, ending the transaction cannot take pl ace until the encoder releases control of the sid line. this happens during the transi tion from when the last bit of the register is output to the receiving of the ack. 7. the graphics controller, acting as the serial master, should clear the check_stat register bit back to 0 (b it d6 of register ba) by writing zero to the check_stat register bit (bit d6 of register ba) to display standard video again from the CX25870/871 vga encoder. to reiterate, a start condition needs to be issued by the serial master to start the next transaction. in the read mode, when the CX25870/871 is driving the sid port, an end to the transact ion cannot take place until the encoder releases control of the sid line. this event happens during the transition from when the last bit of the register is output to the receiving of the ack. table 1-31. estatus[1:0] read-back bit map estatus [1:0] 7 6 5 4 3 2 1 0 00 id[2:0] version[4:0] 01 monstat_a monstat_b monstat_c ccstat_e ccstat_o field[2:0] 10 reserved secam pll_reset_o ut pll_lock fifo_over fifo_ under pal reserved note(s): descriptions of these bits are found in table 2-4 .
1.0 functional description CX25870/871 1.3 device description flicker-free video encoder with ultrascale technology 1-90 conexant 100381b 1.3.47 sleep/ power management there are a number of sleep/power down options for the CX25870/871. these options can be grouped into three differen t categories. the first category pertains to power management during normal operation. dis_pll bit: in nonsleep mode, when an external cl ock is being used, and the pll is not needed, this bit will disable the pll function. xtal_pad_dis bit: setting this bit forces the crystal oscill ator circuit to completely shut down. this requires the CX25870/871 to switch over to an external clock or the reset* pin needs to be pulsed low to recover. xtl_bfo_dis bit: this disables the crystal buf fer when it is not needed. dis_clko bit: this will disable the clko output pin when not needed, i.e., an external clock is used in slave interfa ce or to reduce sleep current. dacdisx/dacoff bits: each individual dac can be powered down by setting its corresponding dacdisx bit. this is useful only if some of the dacs are not being utilized by the graphics system. the entire analog subsection of the device can be powered-down with the dacoff bit, allowing digital operations to continue while reducing the power in th e analog circuitry. this will achieve a significant reduction in power while maintaining all digital functionality. the second category pertains to software enabled sleep operation. sleep_en bit: shuts down all internal clocks except the serial port interface clock. disables all digital i/o pins ex cept these: sleep, altaddr, clki, clko, and xtal_out. disables the pll. turns off all dacs and vref; sleep and reset* are never disabled. pll_keep_alive bit: when the pll is used to provide a system clock, this bit keeps it functioning if the rest of the chip is slept throug h either the sleep pin or sleep bit. this bit has no affect if dis_pll is set. dis_clki bit: the disable for the clki is separate from the sleep bit and sleep pin to accommodate using an external clock as the clock source for the CX25870/871 or as the pll input. the third category relates to the pin driven sleep operation. sleep pin: in addition to what the sleep_en bi t does, the sleep pin shuts down the serial port interface and disables th e altaddr pin. if the sleep pin = 1, the only way the encoder can return to normal operation is by resetting the sleep pin in 0. to achieve additional power savings, all the power management options available in normal operatio n are also available in software or pin driven sleep operation. for the lowest possible power consumption, set the xtl_bfo_dis, dis_clko, dis_clki, and xtal_pad_dis b its in order, then pull the sleep pin (#52) high.
100381b conexant 2-1 2 2.0 internal registers a complete register bit map CX25870/871 is displayed in table 2-1 . all registers are read/write unless denoted otherwise. for bit descriptions and detailed programming information, follow the register bit map below. all registers are set to their default stat e following a software reset. a soft ware reset is always performed at power-up. after power-up, a reset can be trig gered by to writing the sreset register bit. table 2-1. register bit map (* indicates read-only register) (1 of 4) 8-bit address d7 d6 d5 d4 d3 d2 d1 d0 *00 id[2:0] version[4:0] *02 monstat_a monstat_b monstat_c c cstat_e ccstat_0 field_cnt[2:0] *04 reserved secam pll_reset_ out pll_lock fifo_over fifo_under pal reserved *06 monstat_a monstat_b monsta t_c monstat_d field_cnt[3:0] 28 serialtest[7:0] 2e hdtv_en rgb2prpb rpr_sync_d is gy_sync_dis bpb_sync_d is hd_sync_ edge raster_sel[1:0] 30 sleep_en xtal_pad_ dis xtl_bfo_ dis pll_keep_ alive dis_clki dis_pll dis_clko reserved 32 auto_chk drvs[1:0] setup_hold_a dj in_mode[3] datdly_re offset_ rgb csc_sel 34 adpt_ff reserved reserved c_altff[1:0] reserved y_altff[1:0] 36 ffrtn yselect c_thre sh[2:0] y_thresh[2:0] 38 (1) reserved pix_double pll_32clk div2 hburst_ end[8] hburst_ begins[8] v_linesi [10] h_blanki [9] 3a reserved reserv ed reserved 14318_xtal half_clko pll_div10 pll_input div2_ latch 3c mcompy[7:0] 3e mcompu[7:0] 40 mcompv[7:0] 42 msc_db[7:0] 44 msc_db[15:8] 46 msc_db[23:16] 48 msc_db[31:24]
2.0 internal registers CX25870/871 flicker-free video encoder with ultrascale technology 2-2 conexant 100381b 4a dr_limitp[7:0] 4c dr_limitn[7:0] 4e reserved reserved dr_limi tn[10:8] dr_limitp[10:8] 50 db_limitp[7:0] 52 db_limitn[7:0] 54 reserved reserved db_limi tn[10:8] db_limitp[10:8] 56 fil4286incr[7:0] 58 reserved reserved filfsconv[5:0] 5a y_off[7:0] 5c hue_adj[7:0] 5e xdssel[3:0] ccsel[3:0] 60 ewssf2 ewssf1 reserved reserved wsdat[4:1] 62 wsdat[12:5] 64 wsdat[20:13] 66 wssinc[7:0] 68 wssinc[15:8] 6a reserved reserved reserved reserved wssinc[19:16] 6c timing_ rst en_reg_rd ffcbar blnk_ignore e n_scart eactive fld_mode[1:0] 6e hsynoffset[7:0] 70 hsynoffset[9:8] hsynwidth[5:0] 72 reserved 74 datdly datswp rese rved vsynwidth[2:0] 76 (1) h_clko[7:0] 78 (1) h_active[7:0] 7a (1) hsync_width[7:0] 7c (1) hburst_begin[7:0] 7e (1) hburst_end[7:0] 80 (1) h_blanko[7:0] 82 (1) v_blanko[7:0] 84 (1) v_activeo[7:0] 86 (1) v_activeo[ 8] h_active[10:8] h_clko[11:8] table 2-1. register bit map (* indicates read-only register) (2 of 4) 8-bit address d7 d6 d5 d4 d3 d2 d1 d0
CX25870/871 2.0 internal registers flicker-free video encoder with ultrascale technology 100381b conexant 2-3 88 (1) h_fract[7:0] 8a (1) h_clki[7:0] 8c (1) h_blanki[7:0] 8e (1) reserved reserved reserved vblankdly h_blanki[8] h_clki[10:8] 90 (1) v_linesi[7:0] 92 (1) v_blanki[7:0] 94 (1) v_activei[7:0] 96 (1) clpf[1:0] ylpf[1:0] v_activei[9:8] v_linesi[9:8] 98 (1) v_scale[7:0] 9a (1) h_blanko[9:8] v_scale[13:8] 9c (1) pll_fract[7:0] 9e (1) pll_fract[15:8] a0 (1) en_xclk by_pll pll_int[5:0] a2 (1) fm eclip pal_md dis_scrst v sync_dur 625line setup ni_out a4 (1) sync_amp[7:0] a6 (1) bst_amp[7:0] a8 (1) mcr[7:0] aa (1) mcb[7:0] ac (1) my[7:0] ae (1) msc[7:0] b0 (1) msc[15:8] b2 (1) msc[23:16] b4 (1) msc[31:24] b6 phase_off[7:0] b8 (2) reserved config[5:3] reserved config[2:0] ba sreset check_stat slaver dacoff dacdisd dacdisc dacdisb dacdisa bc ccf2b1[7:0] be ccf2b2[7:0] c0 ccf1b1[7:0] c2 ccf1b2[7:0] table 2-1. register bit map (* indicates read-only register) (3 of 4) 8-bit address d7 d6 d5 d4 d3 d2 d1 d0
2.0 internal registers CX25870/871 flicker-free video encoder with ultrascale technology 2-4 conexant 100381b c4 estatus[1:0] eccf2(exds) eccf1 (ecc) eccgate ecbar dchroma en_out c6 en_blanko en_dot fieldi v synci hsynci in_mode[2:0] c8 dis_ylpf dis_ffilt f_selc[2:0] f_sely[2:0] ca dis_g mushy dis_gmshy ycoring[2:0] yattenuate[2:0] cc dis_ gmushc dis_gmshc ccoring[2:0] cattenuate[2:0] ce out_muxd[1:0] out_muxc[1:0] out_muxb[1:0] out_muxa[1:0] d0 ccr_start[7:0] d2 cc_add[7:0] d4 mode2x div2 en_async ccr_start[8] cc_add[11:8] d6 ccr_ start[9] e656 blanki eblue out_mod e[1:0] lumadly[1:0] d8 chroma_ bw by_yccr pkfil_sel[1:0] field_id cvbsd_inv sc_ pattern prog_sc note(s): (1) denotes a register that is reprogrammed by the autoconfiguration process. (2) when sequentially writing a new register set to t he CX25870/871, make sure to skip register 0xb8 . this is the autoconfiguration register and writing to it will overwrite registers 0x76 through 0xb4 and 0x38 with autoconfiguration values. table 2-1. register bit map (* indicates read-only register) (4 of 4) 8-bit address d7 d6 d5 d4 d3 d2 d1 d0
CX25870/871 2.0 internal registers flicker-free video encoder with ultrascale technology 2.1 essential registers 100381b conexant 2-5 2.1 essential registers the power-up state will be either autoconfiguration mode 0 (640 x 480 rgb in ntsc out) or autoconfiguration mode 1 (640 x 480 rgb in, pal_bdghi out) depending on the state of the pal pin. by default, the CX25870/871 will be in master interface. to enable active video, the eactive register bit must be set. 2.2 device address the serial device address for the CX25870/871 is config urable by the state of the altaddr pin at reset. table 2-2 lists how the altaddr pin switches the devices serial address. the altaddr pins state should only be changed during power-up. 2.3 writing registers following a start condition, writing 0x88 as the device id initiates write access to the CX25870/871 registers when the altaddr pin is low. alternative device id 0x8a initiates write access when the altaddr pin is high. if the data is written sequentially in subaddress or der, only the first subaddress needs to be written; the internal address counter will automatically increment after each write to the next register. when writing an entirely new register set to the CX25870/871, make sure to skip register 0xb8. this is the autoconfiguration register, and writing any value to it af ter having loaded values into other registers will replace desired data with unwanted data. table 2-2. serial address configuration altaddr state device address for writing device address for reading 00x88 0x89 1 0x8a 0x8b
2.0 internal registers CX25870/871 2.4 reading registers flicker-free video encoder with ultrascale technology 2-6 conexant 100381b 2.4 reading registers following a start condition, writing 0x89 and then the desired subaddress initiates the read-back sequence. the next eight bits of information, returned by the CX25870/ 871, can be read from the sid pin, most significant bit first. alternative address 0x8b is required if the alt addr pin is high. registers 0x00 through 0x06 are read only. all other registers can be read from or written to. the id[2:0] bits of register 0x00 indicate the part type (CX25870/871 or bt868/869). the lower five bits (version[4:0]) indicate the version nu mber of that particular encoder. for software detection of a connected tv monitor on each dac output, the m onstat_x bits (found in 0x06 and 0x02 for legacy purposes) should be read accordingly after writing to check_stat. for a description of this process follow the guidelines contained in the section 1.3.46 . to check the status of the monitor connections at the dac output automatically once per frame during the vertical blanking interval, set the auto_chk bit. the following pseudocode sample should be used fo r properly reading registers within the CX25870/871. first, there are some basic action assignments: next, load 46 hex into register 6c. this will write the en_reg_rd bit to 1. this enables the serial master to read back all encoder registers. perform the following transaction with the serial master: ? start/d_addr/s_ack/6c /s_ack/46/s_ack/stop next, use the serial master to write the regi ster address from whic h read-back will occur: ? start/d_addr/s_ack//s_ack/stop finally, read the data starting at the read_address pr eviously issued: ? start/d_addr+1/s_ack//m_ack//m_ ack/ /m_ack/.../...//m_ack// nack/stop where: readdata(0) is the data from CX25870/871 register readdata(1) is the data from cx258 70/871 register +1 readdata(2) is the data from cx258 70/871 register +2 as long as the CX25870/871 detects an acknowledge from the serial master (m_ack) after providing the readdata, it will expect the read transactio n to continue. when no acknowledge is received, the encoder will end the read operation. using this approach , consecutive register reads can be provided with less software overhead. to read just one register location, every programming st ep remains the same up to the point where the read data transaction occurs. s_ack the slave device generates the acknowledge (i.e., the CX25870/871) m_ack the serial master generates the acknowledge. nack no acknowledge is generated by either device. start serial start condition; falling ed ge of sid occurs when sic is high. stop serial stop condition; rising edge of sid occurs when sic is high. d_addr the device address is 88 hex with altaddr = 0, 8a when it is a 1.
CX25870/871 2.0 internal registers flicker-free video encoder with ultrascale technology 2.4 reading registers 100381b conexant 2-7 in this case, the master sh ould simply substitute a stop in plac e of the m_ack. the final step of the transaction will therefore be: start/8b/s_ack//nack/stop . table 2-3 contains the bitmap for the encoder?s read-only registers. table 2-4 contains the data details for these registers. as mentioned previously , to enable full register read back, the en_reg_rd bit must be set to 1. table 2-3. bit map for read-only registers register address 7 6 5 4 3 2 1 0 00 id[2:0] version[4:0] 02 monstat_a monstat_b monstat_ c ccstat_e ccstat_o field_cnt[2:0] 04 reserved secam pll_reset_ out pll_lock fifo_over fifo_ under pal reserved 06 monstat_a monstat_b monstat_c monstat_d field_cnt[3:0]
2.0 internal registers CX25870/871 2.4 reading registers flicker-free video encoder with ultrascale technology 2-8 conexant 100381b table 2-4. data details defined for read-only registers bit names data definition id[2:0] indicates the part number of th e conexant vga encoder: 000 is returned from the bt868, 001 is returned from the bt869, 010 is returned from the CX25870, and 011 is returned from the cx25871. version[4:0] version number; for revision a of the CX25870/871, these bits are all 00000. revision c (25870/871-13) is denoted by 00001 of the CX25870/871. revision d (25870/871-14) is de noted by 00010 of the CX25870/871. revision e (25870/871-15) is deno ted by 00011 of the CX25870/871. monstat_a monitor connect ion status for daca output, 1 denot es monitor connected to daca. monstat_b monitor connect ion status for dacb output, 1 denot es monitor connected to dacb. monstat_c monitor connect ion status for dacc output, 1 denot es monitor connected to dacc. monstat_d monitor connecti on status for dacd output, 1 deno tes monitor connected to dacd. ccstat_e high if closed-caption data has been written for the even field; it is low immediately after the clock run-in on the extended service line for the even field. ccstat_o high if closed-caption data has be en written for the odd field; it is lo w immediately after the clock run-in on the closed caption line for the odd field. field_cnt[3:0] field number, where 0000 indi cates the first field, 1111 indicates the 15th field. an extra bit was added to accommodate the secam standard. secam indicates status of secam mode. if the encoder is outputti ng secam, this bit will be set to 1. pll_reset_out pll reset state. pll_lock high when pll is locked. will be low if pll loses lock. fifo_over set to one if fifo overflows. reset on read. fifo_under set to one if fi fo underflows. reset on read. pal indicates status of pal m ode. if the encoder is outputting pal, this bi t will be set to 1. if the encoder is transmitting ntsc, this bit is set to 0.
CX25870/871 2.0 internal registers flicker-free video encoder with ultrascale technology 2.4 reading registers 100381b conexant 2-9 table 2-5 contains the data details for the CX25870/871 read/write registers. table 2-5. programming detail for all read/write registers (1 of 16) bit/register names bit location bit/register definition 14318_xtal bit 4?3a 0 = 13.500 crystal operation. (default) 1 = 14.318 mhz crystal operation. adjusts au toconfiguration register values for the alternative crystal frequency. 625line bit 2?a2 the default state of this bit will be 1 if the pal pin is 1. 0 = 525-line format (nts c-m, ntsc-j, pal-m). 1 = 625-line format (pal-bdghi , pal-n, pal-nc, secam). adpt_ff bit 7?34 0 = disable adapti ve flicker filt er. (default) 1 = enable adaptive flicker filter. auto_chk bit 7?32 0 = normal operation. (default) 1 = the status of the monitor connections w ill be automatically checked once per frame during the vbi (vertical blanking interval). blanki bit 5?d6 0 = active low blank* pin. (default) 1 = active high blank* pin. blnk_ignore bit 4?6c 0 = use bl ank* pin to indicate the active pixe l region in ccir 656 mode. (default) 1 = use registers h_blanki & v_blanki to determine the ac tive pixel region in ccir 656 mode. bpb_sync_dis bit 3?2e this bit is only effective when ou t_mode[1:0] = 11, hdtv_en = 1, and raster_sel is nonzero. 0 = enables trilevel sync on hdtv blue or p b output. (default) 1 = disables trilevel sy nc on hdtv blue or p b output. this bit will have to be set manually for eia-770.3 compliance. bst_amp[7:0] bits[7:0]?a6 color burst amplitude factor. each bit adjustment represents 1.25 mv of burst amplitude. by_pll bit 6?a0 0 = use on chip pll (default) 1 = bypass pll (encoder cloc k is crystal frequency). by_yccr bit 6?d8 0 = norm al operation (default) 1 = bypass luma cross color reduction filter. optimal sta ndard definition quality most often realized with this setting. c_altff[1:0] bits [4:3]?34 chroma alternate flicker filter select ion. this bit will only have an effect when adpt_ff is set. c_altff should always be programmed to a value greater than or equal to f_selc. 00 = 5 line (default) 01 = 2 line 10 = 3 line 11 = 4 line c_thresh[2:0] bits [5:3]?36 controls the se nsitivity or limit of turn ing on the alternate flicker filter for chroma in adaptive mode. (default = 000)
2.0 internal registers CX25870/871 2.4 reading registers flicker-free video encoder with ultrascale technology 2-10 conexant 100381b cattenuate[2:0] bits [2:0]?cc chroma atte nuation. used for saturation control. 000 = 1.0 gain no attenuation (default) 001 = 15/16 gain 010 = 7/8 gain 011 = 3/4 gain 100 = 1/2 gain 101 = 1/4 gain 110 = 1/8 gain 111 = 0 gain (force chroma to 0) cc_add[11:0] bits [3:0]?d4 and bits [7:0]?d2 closed-captioning dto increment. ccf1b1[7:0] bits [7:0]?c0 this is the fi rst byte of closed-capti on information for the odd field, line 21 for ntsc or line 22 for pal. data is encoded lsb first. ccf1b2[7:0] bits [7:0]?c2 this is the se cond byte of closed-caption information for the odd field, line 21 for ntsc or line 22 for pal. data is encoded lsb first. ccf2b1[7:0] bits [7:0]?bc this is the first byte of closed-c aption information for the even field, line 284 for ntsc or line 335 for pal. data is encoded lsb first. ccf2b2[7:0] bits [7:0]?be this is the second byte of cl osed-caption information for the even field, line 284 for ntsc or line 335 for pal. data is encoded lsb first. ccoring[2:0] bits [5:3]?cc chroma cori ng. values below the ccoring[2:0] lim it are automatically clamped to a saturation value of 0. 000 = bypass (default) 001 = 1/128 of range ( 1/256 of range) 010 = 1/64 of range ( 1/128 of range) 011 = 1/32 of range ( 1/64 of range) 100 = 1/16 of range ( 1/32 of range) 101 = 1/8 of range ( 1/16 of range) 110 = 1/4 of range ( 1/8 of range) 111 = reserved ccr_start[9] ccr_start[8] ccr_start[7:0] bit 7 of d6, bit 4 of d4, and bits [7:0] of d0 closed-captioning clock run-in start in cl ock cycles from lead ing edge of hsync*. ccsel[3:0] bits [3:0]?5e li ne position of closed captioning (cc) content. controls which line closed captioning (cc) data is enc oded. each lin e enable is independent. 0001 = closed captioning (cc) on line 19 (525-line) and line 21 (625-line) 0010 = closed captioning (cc) on line 20 (525-line) and line 22 (625-line) 0100 = closed captioning (cc) on line 21 (525-line) and line 23 (625-line) (default) 1000 = closed captioning (cc) on line 22 (525-line) and line 24 (625-line) check_stat bit 6?ba writing a 1 to this bit checks the status of the mo nitor connections at the dac output. this is also automatically performed on any reset condition, including a software reset. this bit must be cleared by the serial interface master. chroma_bw bit7?d8 0 = normal chroma bandwidth. see figure 1-28 (default). 1 = wide chroma bandwidth. see figure 1-29 . table 2-5. programming detail for all read/write registers (2 of 16) bit/register names bit location bit/register definition
CX25870/871 2.0 internal registers flicker-free video encoder with ultrascale technology 2.4 reading registers 100381b conexant 2-11 clpf[1:0] bits [7:6]?96 chroma post-flicker f ilter/scaler horizontal low pass filter: 00 = bypass (default) 01 = reserved 10 = chroma horizontal lpf2 setting 11 = chroma horizontal lpf3 setting table 2-5. programming detail for all read/write registers (3 of 16) bit/register names bit location bit/register definition
2.0 internal registers CX25870/871 2.4 reading registers flicker-free video encoder with ultrascale technology 2-12 conexant 100381b config[5:0] bits [6:4] and bits [2:0]?b8 the combination of config[5:3] and config [2:0] determines the autoconfiguration mode entered by the CX25870/871 immediately after register 0xb8 is written. check appendix c for a list of all register valu es by autoconfiguration mode. table 2-5. programming detail for all read/write registers (4 of 16) bit/register names bit location bit/register definition config [5:0] input format active resolution output output ratio mode 000000 = rgb 640x480 ntsc overscan = lower mode 0 000001 = rgb 640x480 pal-bdghi ove rscan = standard mode 1 000010 = rgb 800x600 ntsc overscan = alternate mode 2 000011 = rgb 800x600 pal-bdghi overscan = lower mode 3 000100 = ycrcb 640x480 ntsc overscan = lower mode 4 000101 = ycrcb 640x480 pal-bdghi ove rscan = standard mode 5 000110 = ycrcb 800x600 ntsc overscan = alternate mode 6 000111 = ycrcb 800x600 pal-bdghi overscan = lower mode 7 001000 = rgb 640x400 ntsc overscan = standard mode 8 001001 = rgb 640x400 pal-bdghi ove rscan = standard mode 9 001010 = rgb 1024x768 ntsc overscan = standard mode 10 001011 = rgb 1024x768 pal-bdghi ove rscan = standard mode 11 001100 = rgb 320x240 ntsc pix doubl e set = standard mode 12 001101 = rgb 320x240 pal-bdghi pix d ouble set = standard mode 13 001110 = ycrcb 1024x768 ntsc overscan = higher mode 14 001111 = ycrcb 1024x768 pal-bdghi o verscan = higher mode 15 010000 = reserved mode 16 010001 = rgb 640x480 pal-bdghi overscan = lower mode 17 010010 = rgb 800x600 ntsc overscan = lower mode 18 010011 = rgb 800x600 pal-bdghi ove rscan = standard mode 19 010100 = reserved mode 20 010101 = ycrcb 640x480 pal-bdghi overscan = lower mode 21 010110 = ycrcb 800x600 ntsc overscan = lower mode 22 010111 = ycrcb 800x600 pal-bdghi ove rscan = standard mode 23 011000 = rgb 720x400 ntsc 9-dot font for dos overscan =standard mode 24 011001 = rgb 720x400 pal-bdghi 9-dot font for dos overscan =standard mode 25 011010 = rgb 1024x768 ntsc overscan = lower mode 26 011011 = reserved mode 27 011100 = ycrcb 720x480 ntsc interlaced input, slave interface overscan = 0% div2 set mode 28
CX25870/871 2.0 internal registers flicker-free video encoder with ultrascale technology 2.4 reading registers 100381b conexant 2-13 csc_sel bit 0?32 this bit is only e ffective when out_mode[ 1:0] = 11, hdtv_en = 1, and raster_sel is nonzero. 0 = standard color space conversion for rgb to y (r-y) (b-y) based on y =0 .299r +0 .587g +0 .114 b (default) 1 = hdtv color space conversion fo r rgb to y (r-y) (b-y) based on y = 0.2126r + 0.7152g + 0.0722b cvbsd_inv bit 2?d8 0 = norm al operation. (default) 1 = invert cvbs_dly output. dacdisa bit 0?ba no more than 1 dac should be disabled at any time. 0 = normal operation. (default) 1 = disables daca output. current is set to 0 ma; output will go to 0 v. dacdisb bit 1?ba no more than 1 dac should be disabled at any time. 0 = normal operation. (default) 1 = disables dacb output. current is set to 0 ma; output will go to 0 v. table 2-5. programming detail for all read/write registers (5 of 16) bit/register names bit location bit/register definition 011101 =ycrcb 720x576 pal-bdghi interlaced input, slave interface overscan = 0% div2 set mode 29 01111 0 = ycrcb 1024x768 ntsc overscan = lower mode 30 011111 = reserved mode 31 100000 = rgb 640x480 ntsc overscan = higher mode 32 100001 = rgb 640x480 pal-bdghi o verscan = higher mode 33 100010 = rgb 800x600 ntsc overscan = higher mode 34 100011 = rgb 800x600 pal-bdghi o verscan = higher mode 35 100100 = ycrcb 640x480 ntsc overscan = higher mode 36 100101 = ycrcb 640x480 pal-bdghi overscan = higher mode 37 100110 = ycrcb 800x600 ntsc overscan = higher mode 38 100111 = ycrcb 800x600 pal-bdghi overscan = higher mode 39 101000 = rgb 800x600 ntsc overscan = standard mode 40 101001 = rgb 320x200 pal-bdghi pix double set overscan = standard mode 41 101010 = rgb 1024x768 ntsc overscan = higher mode 42 101011 = rgb 1024x768 pal-bdghi o verscan = higher mode 43 101100 = rgb 720x480 ntsc noninterlaced input for dvd overscan = very low mode 44 101101 = rgb 320x200 ntsc pix double set overscan = standard mode 45 101110 = rgb 640x480 pal-m (brazil) overscan = standard mode 46 101111 = rgb 640x480 pal-nc (argentina) overscan = standard mode 47
2.0 internal registers CX25870/871 2.4 reading registers flicker-free video encoder with ultrascale technology 2-14 conexant 100381b dacdisc bit 2?ba no more than 1 dac should be disabled at any time. 0 = normal operation. (default) 1 = disables dacc output. current is set to 0 ma; output will go to 0 v. dacdisd bit 3?ba no more than 1 dac should be disabled at any time. 0 = normal operation. (default) 1 = disables dacd output. current is set to 0 ma; output will go to 0 v. dacoff bit 4?ba 0 = normal operation. (default) 1 = disables dac output current and internal voltage reference for all dacs. this will limit power consumption to just the internal digital circuitry. datdly bit 7?74 0 = no delay in fall ing edge pixel data. (default) 1 = delays the falling e dge pixel data by 1 full clock period. this bi t is used to correct a multiplexed input data sequence that delivers a pixel on a falling edge a nd the following rising edge (rather than a rising edge and the following falling edge, as expected). datdly_re bit 2?32 0 = no delay in rising edge pixel data. (default) 1 = delays the rising edge pixel data by 1 full clock period. thi s bit is used together with datswp to correct a multiple xed input data seque nce that delivers a pixel on a falling edge and the following rising e dge with the falling edge and rising edge data swapped. datswp bit 6?74 0 = vga encoder expect s an order of rising e dge data/falling edge data coming from the graphics contro ller (default). 1 = swaps the falling edge pixe l data with the rising edge pi xel data at the input of the pixel port. db_limitn[10:8} db_limitn[7:0] bits [5:3]?54 and bits [7:0]?52 lower bound limit for db frequency deviati on in secam. review secam output section. db_limitp[10:8} db_limitp[7:0] bits [2:0]?54 and bits [7:0]?50 upper bound limit for db fre quency deviation in secam. re view secam output section. dchroma bit 1?c4 0 = norm al operation. (default) 1 = disable the chrominance portion of vi deo output. composite and s-video outputs appear as gray scale. dis_clki bit 3?30 0 = normal operation. (default) 1 = disable clki input. disabling the clki input is se parate from the sleep bit an d sleep pin. this forces the CX25870/871 to use an external clock as the clock source for the CX25870/871 or as the pll input. dis_clko bit 1?30 0 = enable clko output. (default) 1 = three-state clko output. this will disable the clko output when not needed, i.e., an external clock is used (slave interface). disabling clko is also effective in reducing the current draw in sleep mode. dis_ffilt bit 6?c8 0 = enables stan dard flicker f ilter. (default) 1 = disables standard flicker filter. dis_gmshc bit 6?cc 0 = enables chroma pseudo gamma removal. 1 = disables chroma pseudo gamma removal. (default) dis_gmshy bit 6?ca 0 = enables luma pseudo gamma removal. 1 = disables luma pseudo gamma removal. (default) dis_gmushc bit 7?cc 0 = enables ch roma anti-pseudo gamma removal. 1 = disables chroma anti-pse udo gamma removal. (default) table 2-5. programming detail for all read/write registers (6 of 16) bit/register names bit location bit/register definition
CX25870/871 2.0 internal registers flicker-free video encoder with ultrascale technology 2.4 reading registers 100381b conexant 2-15 dis_gmushy bit 7?ca 0 = enables luma anti-pseudo gamma removal. 1 = disables luma anti-pse udo gamma removal. (default) dis_pll bit 2?30 0 = pll enable. (default) 1 = pll disable. in nonsleep mode, if an external clock is be ing used and the pll is not needed, this bit will disable the pll function. note(s): some of the special modes are not av ailable when the pll is disabled. dis_scrst bit 4?a2 0 = normal operation. the subcarrier phase is reset to 0 at the beginning of each color field sequence. (default) 1 = disables subcarrier reset ev ent at beginning of field sequence. dis_ylpf bit 7?c8 0 = enable luma initial horizontal low pass filter. (default) 1 = disable luma initial horizontal low pass filter. div2 bit 6?d4 and bit 4?38 0 = normal operation. (default) 1 = divides input pixel rate by two (for cc ir601 interlaced timing input). useful for dvd playback resolutions. the div2 bit in regist er d4 was kept for bt868/869 compatibility purposes. the div2 bit in register 38 is auto configurable. these bit values always mirror each other. changing the state of one div2 register field automati cally updates the other div2 register field. div2_latch bit 0?3a this bit only has an effect when div2 = 1. 0 = data is clocked at rising edge of clki while encoder is in div2 mode. (default) 1 = data is clocked at risi ng and falling edges of clki. dr_limitn[10:8} dr_limitn[7:0] bits [5:3]?4e and bits [7:0]?4c lower bound limit for dr frequency deviat ion in secam. review secam output section. dr_limitp[10:8} dr_limitp[7:0] bits [2:0]?4e and bits [7:0]?4a upper bound limit for dr frequency deviation in secam. review secam output section. drvs[1:0] bits [6:5]?32 controls the low voltage pad dr ive strength. review low voltage graphics interface section. 00 = 3.3 v peak-to-peak signal levels (default) 01 = 1.8 v peak-to-peak signal levels 10 = 1.5 v and 1.3 v peak-to-peak signal levels 11 = 1.1 v peak-to-peak signal levels e656 bit 6?d6 0 = input pixel format define d by in_mode[3:0] register. (default) 1 = ccir 656 input on p[7:0] port. eactive bit 2?6c 0 = black burst. 1 = enable normal video. (default) eblue bit 4?d6 0 = normal operation. (default) 1 = generate blue field. ecbar bit 2?c4 0 = normal operation. (default) 1 = enable standard color bars. eccf1(ecc) bit 4?c4 0 = disa bles closed-caption encoding on field 1. (default) 1 = enables closed-caption encoding on field 1. eccf2(exds) bit 5?c4 0 = di sables closed-caption enc oding on field 2. (default) 1 = enables closed-caption encoding on field 2. table 2-5. programming detail for all read/write registers (7 of 16) bit/register names bit location bit/register definition
2.0 internal registers CX25870/871 2.4 reading registers flicker-free video encoder with ultrascale technology 2-16 conexant 100381b eccgate bit 3?c4 0 = normal clos ed-caption encoding. (default) 1 = enables closed-caption encoding constrai nts. after encoding, future encoding is disabled until a complete pair of new data bytes is recei ved. this prevents encoding of redundant or incomplete data. eclip bit 6?a2 0 = normal operation. (default) 1 = enable clipping; dac va lues less than 31 hex are made 31 by the encoder. en_async bit 5?d4 0 = norm al operation. (default) 1 = enable asynchronous flicke r filer and encoder block ti ming operation. use clki for flicker filter and input blocks and pll for encoder block. allows for additional clock ratios between flicker filter and encoder bl ocks to provide more overscan solutions similar to the 3:2 clocking mode. en_blanko bit 7?c6 interface bit: works in conjunc tion with en_dot, en_out, and slaver. controls direction of blank* signal. 0 = enables blank* as an input. 1 = enables blank* pin as an output, or no blank* signal is utilized in the system interface. (default) en_dot bit 6?c6 interface bi t: works in conjunction with en_bla nko, en_out, and slaver. controls blanking method. 0 = encoder uses its internal counters to de termine the active-versu s-blanked regions of input data. (default) 1 = encoder uses the blank* signal being re ceived to determine where active video starts (rising edge by default) and where blanking region starts (falling edge by default). en_out bit 0?c4 interface bit: works in conjunction with en_b lanko, en_dot, a nd slaver. turns timing outputs on or off. 0 = three-state (clko, hsync*, vsync* , blank* and field) timing outputs. (default) 1 = allows clko and other out puts to be enabled (depending upon en_blanko register bit and the or combination of the slave pin and the slaver bit). en_reg_rd bit 6?6c 0 = use estatus[1:0] register to se lect read back status registers. enable bt869-like legacy read-back method. (default) 1 = enable standard serial register read back of all registers. en_scart bit 3?6c enables scart video output for europe . out_mode[1:0] field mu st be set to 11 (vga mode) and hdtv_en bit must be set to 0. 0 = enables vga mode. dacs will output an alog rgb with standard bilevel (-40 ire) analog syncs (default). 1 = enables scart output mode. dac will tr ansmit scart compatible rgb outputs and a composite video output whic h includes an analog sync. en_xclk bit 7?a0 0 = encoder gene rates pixel clock. (default) 1 = use clki pin as pixel clock source. this bit must be set for slave interface. estatus[1:0] bits [7:6]?c4 bt868/869 lega cy serial read back st atus bit selection. us ed in conjunction with en_reg_rd, check_stat, and auto_chk. review table 1-30 . ewssf1 bit 6?60 0 = disable field 1 wss data. (default) 1 = enable field 1 wss data. ewssf2 bit 7?60 0 = disable field 2 wss data. (default) 1 = enable field 2 wss data (525 line only). table 2-5. programming detail for all read/write registers (8 of 16) bit/register names bit location bit/register definition
CX25870/871 2.0 internal registers flicker-free video encoder with ultrascale technology 2.4 reading registers 100381b conexant 2-17 f_selc[2:0] bits [5:3]?c8 chroma standard flicker filter: 000 = 5 line (default) 001 = 2 line 010 = 3 line 011 = 4 line 100 = alternate 5 line 101 = alternate 5 line 110 = alternate 5 line 111 = alternate 5 line f_sely[2:0] bits [2:0]?c8 luma standard flicker filter: 000 = 5 line (default) 001 = 2 line 010 = 3 line 011 = 4 line 100 = alternate 5 line 101 = alternate 5 line 110 = alternate 5 line 111 = alternate 5 line ffcbar bit 5?6c 0 = normal operation. (default) 1 = enable flicker filtered color bars. ffrtn bit 7?36 alternate flicker filter detect and select. this bit is effective only when adpt_ff = 1. 0 = once the adaptive algorithm selects the altern ate filter, use that filter?s coefficients for the rest of the samples for that line. for example, the sequence could be std/std/alt/alt/alt; (default) 1 = once the adaptive algorithm selects the alte rnate filter, use the filter?s coefficients for that sample only. for example, th e sequence with ffrtn=1 could be std/std/alt/std/std. field_id bit 3?d8 0 = suppress the secam fi eld synchronization signal. (default) 1 = enable the secam field synchroni zation signal (bottle-neck pulses). fieldi bit 5?c6 0 = logical 1 fr om the field pin indicates an even field. (default) 1 = logical 1 from the field pin indicates an odd field. filfsconv[5:0] bits [5:0]?58 adjust secam high frequency preemphasis filter accordi ng to the clock frequency. review the secam output sect ion for the correct equations. fil4286incr[7:0] bits [7:0]?56 adds a phas e offset to the uv digital components. review the secam output sect ion for the correct equations. fld_mode[1:0] bits [1:0]?6c CX25870/871 uses this bit to inte rpret hsync* and vsync* ed ges and field detection in slave mode. 00 = a leading edge of vsy nc* that occurs within 1/4 of hclki from the leading edge of hsync* indicates the begi nning of odd field. a leading edge of vsync* that occurs within 1/4 of hclki from the center of the lin e indicates the beginning of even field. 01 = a leading edge of vsync* occurs duri ng hsync* active indicates the beginning of odd field. a leading edge of vsync* occurs during hsyn c* inactive indicates the beginning of even field. 10 = a leading edge of vsync* coincides with the leading e dge of hsync* indicates the beginning of odd field. a leading edge of vsync* does not coincide with the leading edge of hsync* indica ted the beginning of even field. (default) 11 = reserved. table 2-5. programming detail for all read/write registers (9 of 16) bit/register names bit location bit/register definition
2.0 internal registers CX25870/871 2.4 reading registers flicker-free video encoder with ultrascale technology 2-18 conexant 100381b fm bit 7?a2 this bit must be enabled for a valid secam video output. 0 = qam color encoding (ntsc/pal). (default) 1 = fm color encoding (secam). gy_sync_dis bit 4?2e this bit is only effective when ou t_mode[1:0] = 11, hdtv_en = 1, and raster_sel is nonzero. 0 = enables trilevel sync on hdtv green or y output. (default) 1 = disables trilevel sync on hdtv green or y output. h_active[10:8] h_active[7:0] bits [6:4]?86 and bits [7:0]?78 number of active i nput and output pixels. h_blanki[9] h_blanki[8] h_blanki[7:0] bit 0?38, bit 3?8e, and bits[7:0]?8c number of clki clock cycles between the di gital hsync* leading edge and first active pixel. h_blanko[9:8] h_blanko[7:0] bits [7:6]?9a and bits [7:0]?80 number of clko clock cycles between leadi ng edge of analog horiz ontal sync and active video. h_clki[10:8] h_clki[7:0] bits [2:0]?8e and bits [7:0]?8a number of clki clock cycles between consec utive leading edges of the digital hsync* signal. h_clko[11:8] h_clko[7:0] bits [3:0]?86 and bits [7:0]?76 number of clko clock cycles per analog line. h_fract[7:0] bits [7:0]?88 fractional number of input clocks per li ne. no effect if 00. half_clko bit 3?3a 0 = norm al operation. (default) 1 = clko (clock output) frequency divided by 2 while being transmitted. hburst_begin[8] hburst_begin [7:0] bit2?38 and bits [7:0]?7c this register contains the number of clko clock cycles between the analog horizontal sync falling edge and the 50% point of the first colorburst cycle. hburst_end[8] hburst_end[7:0] bit 3?38 and bits [7:0]?7e this register contains the number of clko clock cycles minus 128 between the analog horizontal sync falling edge and the 50% point of the last colo rburst cycle. make sure to subtract 128 clko clock cycles from the ca lculated 50% point of the last colorburst cycle value and load into this register. hd_sync_edge bit 2?2e this bit is only effective when out_mode[1:0] = 11, hdtv _en = 1 and raster_sel is nonzero. 0 = trilevel sync edges transition time is equal to 4 input clocks. (default) 1 = trilevel sync edges transition ti me is equal to 2 input clocks. hdtv_en bit 7?28 enable hdtv output m ode, out_mode[1:0] register bits must be set to 11 (vga mode) and en_scart must = 0. 0 = enables vga mode. dacs will output an alog rgb with standard bilevel (-40 ire) analog syncs. (default) see section 1.3.45 for details. 1 = enables hdtv output mode . dacs will output hdtv compatible rgb or component video (y/ p r / p b ) outputs. trilevel syncs and vertical synchronizing/broad pulses will be inserted automatically if raster_sel[1:0] = nonzero. note(s): the en_scart bit must be 0 for hd tv output mode to be functional. hsync_width [7:0] bits [7:0]?7a analog horiz ontal sync width in numbe r of clko clock cycles. table 2-5. programming detail for all read/write registers (10 of 16) bit/register names bit location bit/register definition
CX25870/871 2.0 internal registers flicker-free video encoder with ultrascale technology 2.4 reading registers 100381b conexant 2-19 hsynci bit 3?c6 0 = configures the encoder to se nd/receive an active lo w hsync* digital signal (default) 1 = configures the encoder to send/receiv e an active high hs ync* digi tal signal. hsynoffset[9:8] hsynoffset[7:0] bits [7:6]?70 and bits [7:0]?6e a 2s-complement number. the values range from ?512 pixels to +511 pixels. this register manipulates the falli ng edge position of the digita l hsync* output from the CX25870/871. the defaul t value is 0 and denotes the st andard position of the hsync* leading edge. this register is onl y effective in master interface. hsynwidth[5:0] bits [5:0]?70 c ontrols the duration/width of the digital h sync output pulse. value will be hexadecimal and its units are in terms of pixels. a value of 0 is a disallowed co ndition. the acceptable range is 0x02 pixels to 0x3f pi xels (=63 decimal). the defaul t value is 0x02. never set to 0. this register is only effective in master interface. hue_adj[7:0] bits [7:0]?5c adjust the color subcarrier phase during the video active region. increasing this value by 1 unit has the effect of increasing the phase by (360/256) = 1.406 degrees. in_mode[3] and in_mode[2:0] bit 3?32 and bits [2:0]?c6 this bit is used in conjunction with in_mod e[2:0] to configure the encoder to receive a desired input pixel format. form at of input pixels when in_mode[3] = 0 (msb of this 4-bit sequence): 0000 = 24-bit rgb multiplexed 0001 = 16-bit rgb multiplexed 0010 = 15-bit rgb multiplexed 0011 = 24-bit rgb nonmultiplexed 0100 = 24-bit ycrcb multiplexed 0101 = 16-bit ycrcb multiplexed 0110 = alternate 16-bit ycrcb multiplexed 0111 = 24-bit ycrcb nonmultiplexed format of input pixels when in_mode[ 3] = 1(msb of this 4-bit sequence): 1000 = alternate 24-b it rgb multiplexed 1001 = reserved 1010 = alternate 16-b it rgb nonmultiplexed 1011 = alternate 24-b it rgb nonmultiplexed 1100 = alternate 24-bit ycrcb multiplexed 1101 = reserved 1110 = alternate 16-bit ycrcb nonmultiplexed 1111 = alternate 24-bit ycrcb nonmultiplexed lumadly[1:0] bits [1:0]?d6 used to program the lumina nce delay in pixe ls for the cvbs_dly and y_dly output modes. 00 = no delay (default) 01 = 1 pixel 10 = 2 pixels 11 = 3 pixels mcb[7:0] bits [7:0]?aa multiplication factor for cb (or b-y) component prior to subcarrier modulation. mcompu[7:0] bits [7:0]?3e multiplication factor for component video u output. value 0x80 (default) represents 1.0 scale factor. mcompv[7:0] bits [7:0]?40 multiplication factor for component video v output. value 0x80 (default) represents 1.0 scale factor. mcompy[7:0] bits [7:0]?3c multiplication factor for component video y output. value 0x80 (default) repres ents 1.0. scale factor. mcr[7:0] bits [7:0]?a8 multiplication factor for cr (or r-y) component prior to subcarrier modulation. table 2-5. programming detail for all read/write registers (11 of 16) bit/register names bit location bit/register definition
2.0 internal registers CX25870/871 2.4 reading registers flicker-free video encoder with ultrascale technology 2-20 conexant 100381b mode2x bit 7?d4 0 = norm al operation (default). 1 = divides selected input cloc k by two (allows for single edge rather than double-edge clock input for pixel latching). msc[31:0] bits [7:0]?b4, b2, b0, ae subcarrier increment. msc_db[31:0] bi ts [7:0]?48, -46, -44, -42 subcarrier increment for db component of secam. msc_db = int ((272/h_clko) * 2 32 + 0.5) my[7:0] bits [7:0]?ac multiplicati on factor for luma component. cont rols adjustment of contrast. ni_out bit 0?a2 0 = interlaced analog video output. (default) 1 = noninterlaced analog video output. offset_rgb bit 1?32 this bit is only e ffective when out_mode[ 1:0] = 11, hdtv_en = 1, and raster_sel is nonzero. 0 = standard rgb digita l input. range is 0 ? 255 decimal. (default) 1 = hdtv offset rgb digital input. range is 16 ? 235 decimal. out_mode[1:0] bits [3:2]?d6 00 = video[0] = composite (cv bs), video[1] = luminance (y ), video[2] = chrominance (c), video[3] = luma_delay (y_dly) (default) 01 = video[0-3] is cvbs_dly/ y/ c/ y_dly 10 = video[0-3] is v/ y/ u/ y_dly 11 = video[0-3] is vga (rgb/x), scart , or hdtv output mode. see en_scart and hdtv_en bit descriptions fo r more programming detail. out_muxa[1:0] bits [1:0]?ce 00 = output vide o[0] on daca (default = composite (cvbs)) 01 = output video[1] on daca 10 = output video[2] on daca 11 = output video[3] on daca out_muxb[1:0] bits [3:2]?ce 00 = output video[0] on dacb 01 = output video[1] on dacb (default = luminance (y) 10 = output video[2] on dacb 11 = output video[3] on dacb out_muxc[1:0] bits [5:4]?ce 00 = output video[0] on dacc 01 = output video[1] on dacc 10 = output video[2] on d acc (default = chrominance) 11 = output video[3] on dacc out_muxd[1:0] bits [7:6]?ce 00 = output video[0] on dacd 01 = output video[1] on dacd 10 = output video[2] on dacd 11 = output video[3] on dacd (default = luma delay (y_dly)) pal_md bit 5?a2 video output switch bit after power-up. 0 = disable phase alternation (ntsc and secam). (default) 1 = enable phase alternation (pal). note(s): the pal pin (#50) determines the powe r-up standard definition video output. this bit overrides the pal pin after power-up. phase_off[7:0] bits [7:0]?b6 subcarrier phase offset. de fault value is 00. sch phase increased by 1.406 degrees per bit increment. table 2-5. programming detail for all read/write registers (12 of 16) bit/register names bit location bit/register definition
CX25870/871 2.0 internal registers flicker-free video encoder with ultrascale technology 2.4 reading registers 100381b conexant 2-21 pix_double bit 6?38 low resolution pixel doubling bit. 0 = encoder accepts each pixel input i ndividually and proc esses it. (default) 1 = encoder replicates/copies ea ch input pixel received. this bit is automatically set for autoconfiguration modes #12, #13, and #41. pkfil_sel[1:0] bits [5:4]?d8 text sharpening filter. also refe rred to as the luma peaking filter selection (refer to section 1.3.36 and figure 1-27 for details). 00 = bypass (default) 01 = filter 1 (1 db gain) 10 = filter 2 (2 db gain) 11 = filter 3 (3.5 db gain) pll_32clk bit 5?38 use this bit primarily to support the 1024 x 768 resolution and additional 800 x 600 overscan options. for more details, re view the 3:2 clocking mode section. 0 = use pll 3x pixel clock output. (default) 1 = use pll generated 2x pixel clock to r un the encoder and output timing section. use pll generated 3x pixel clock to run the flicker filter. note(s): the 3x pixel clock will be output from the clko pin during either state of this bit. pll_div10 bit 2?3a scales the clko frequency. (see section 1.3.6 for details) 0 = pll equation divided by 6. (default) 1 = pll equation divided by 10. pll_fract[15:0] bits [7:0 ]?9e, -9c fractional portion of pll multiplier. pll_input bit 1?3a 0 = pll uses the crystal between xtalin and xtalou t pins to generate the clko programmed frequency. (default) 1 = pll uses clki/2 as the reference for the pll. pll_int[5:0] bits [5:0]?a0 inte ger portion of pll multiplier. pll_keep_alive bit 4?30 0 = no rmal operation. (default) 1 = keeps pll enabled during the sleep m ode. this bit is overwritten by dis_pll. if the pll is used to provide a system clock, this bit keeps it functi oning if the rest of the chip is slept through either the sleep pin or sl eep bit. this bit has no affect if dis_pll is set. prog_sc bit 0?d8 secam subcarrier control bit. prog_sc only has an effect when fm bit is set. 0 = secam subcarrier is generate d on lines 23?310 and 336?623. (default) 1 = secam subcarrier is generated on the ac tive lines defined by v_blanko[7:0] and v_activeo[8:0]. raster_sel[1:0] bits [1:0]? 28 this bit is only effective when hdtv_en = 1, and out_mode[1:0] = 11 00 = device does not generate trilevel sync automatically in hdtv output mode. trilevel sync periods dictated by ac tive hsync* input signal (as highsync) and ac tive vsync* input signal (as lo wsync). (default) 01 = trilevel sync generation for 480p format. 10 = trilevel sync generation for 720p format. 11 = trilevel sync genera tion for 1080i format. regfsconv[5:0] bits [5:0]?58 works in conjunction with fil_4286incr[7:0] to set gain on uv digital component. review the secam output section for the correct equations. reserved various reserved for future software compatibility; should be set to 0 for normal operation. table 2-5. programming detail for all read/write registers (13 of 16) bit/register names bit location bit/register definition
2.0 internal registers CX25870/871 2.4 reading registers flicker-free video encoder with ultrascale technology 2-22 conexant 100381b rgb2yp r p b bit 6?28 hdtv output switching bit. this bi t is only effective when hdtv_en = 1, out_mode[1:0] = 11, raster_sel[1:0] = no nzero, and in_mode[3:0] = a rgb input format. 0 = digital rgb input to hdtv rgb output. (default) 1 = digital rgb input to hdtv yp r p b output. rpr_sync_dis bit 5?28 this bit is only effective when ou t_mode[1:0] = 11, hdtv_en = 1, and raster_sel is nonzero. 0 = enables trilevel sync on hdtv red or p r output. (default) 1 = disables trilevel sync on hdtv red or p r output. this bit will ha ve to be set manually for eia-770.3 compliance. sc_pattern bit 1?d8 secam phase sequence. sc_patter n only has an effect when fm bit is set. 0 = 0 0 180 0 0 180 secam subcarrier phase sequence. (default) 1 = 0 0 0 180 180 180 secam subcarrier phase sequence. serialtest[7:0] bits [7:0]?28 use this register for testing the write and read ability of the serial master. a consecutive write and read sequence will return the original value. the default value is 0x00. setup bit 1?a2 0 = setup off. the 7.5 ire pedestal setup is disabled for active video lines (ntsc-j, pal, and secam). 1 = setup on. the 7.5 ire pede stal setup is enabled for active video lines (ntsc-m). (default) setup_hold_adj bit 4?32 0 = graphic port inputs must have minimum setup = 3 ns, hold = 0 ns (default). this setting is compatible with bt868/869. 1 = graphics port inputs must have minimu m setup = 1.25 ns, hold = 1.5 ns. this is a new option for interfacing the CX25870/ 871 to other data master devices. slaver bit 5?ba interface bit: work s in conjunction with en_blanko, en_dot, and en_out controls whether the interface will be timing master or timing slave. 0 = configures encoder as the timing master . hsync* and vsync* will be transmitted as outputs when this bit or a combination of this bit and slave pin is 0. (default) 1 = configures encoder as th e timing slave (pseudo-master or slave interface). hsync* and vsync* will be received as inputs when this bit or a combination of this bit and slave pin is 1. sleep_en bit 7?30 0 = normal operation. (default) 1 = enables sleep state. shuts down all internal clocks except the serial port interface clock. disables all digital i/o pins except: sleep, altaddr, clki, cl ko, and xtalout. disables the pll. turns off all dacs and vref . sleep and reset* pins are never disabled. sreset bit 7?ba 0 = normal operation. (default) 1 = setting this bit performs a so ftware reset. all registers are reset to their default state. this bit is automatically cleared. sync_amp[7:0] bits [7:0]?a4 multip lication factor for controlling the analog sync amplitude. sync_amp + 1 lsb (least significant bit) = +1.25 mv increase in the analog sync amplitude. timing_rst bit 7?6c 0 = normal operation. (default) 1 = enable timing reset. resets timing and pi xel counters to 1 this bit is auto matically cleared. the designer should wait a minimum of 1 ms, after the last re gister write before enabling timing_rst. v_activei[9:8] v_activei[7:0] bits [3:2]?96 and bits [7:0]?94 number of active input lines. table 2-5. programming detail for all read/write registers (14 of 16) bit/register names bit location bit/register definition
CX25870/871 2.0 internal registers flicker-free video encoder with ultrascale technology 2.4 reading registers 100381b conexant 2-23 v_activeo[8] v_activeo[7:0] bit 7?86 and bits [7:0]?84 number of active output lines/field. v_blanki[7:0] bits [7:0 ]?92 number of input lines between vsync* leading edge and first active line. v_blanko[7:0] bits [7:0]?82 line number of first active output line (number of blank lines + 1). v_linesi[10] v_linesi[9:8] v_linesi[7:0] bit 1?38, bits [1:0]?96, bits [7:0]?90 number of vertical input lines. this register value must match the graphic controller?s vtotal register for a new overscan ratio. v_scale[13:8] v_scale[7:0] bits [5:0]?9a and bits {7:0]?98 vertical scaling coefficient. vsr = v_activei / (alo * (1 ? voc)) v_scale[13:0] = (int) ((vsr ? 1) * 2 12 ) vblankdly bit 4?8e 0 = norm al operation. (default) 1 = the effective vertical blanking value in the se cond field is v_blanki+1. commonly used in ccir601 input. no effect if 0. vsync_dur bit 3?a2 0 = generates 2.5 line vsync analog output (found in equaliza tion and serration pulse region). common for most pal and secam formats. 1 = generates 3 line vsync analog output (found in equaliz ation and serration pulse region). common for all ntsc, pal-n, pa l-m, and pal-60 formats. (default) vsynci bit 4?c6 0 = CX25870/871 transmits or rece ives active digital low vsync*. (default) 1 = CX25870/871 transmits or receiv es active digi tal high vsync*. vsynwidth[2:0] bits [2:0]?74 controls the width of the vsync* output puls e. denotes the number of lines the vsync* digital signal remains low on field transitions. value will be hexadecimal and its units are in terms of lines. a value of 0 is a disallowed condi tion. the acceptable range is 1 line to (2 3 ?1) lines. the default value is 1. never set to 0. this register is only effective in master interface. wssdat[20:1] bits [7:0]?64, - 62, and bits [3:0]?60 wide screen signaling (wss) data bits. review wss section for more details. wssinc[19:0] bits [3:0]?6a and bits [7:0]?68, - 66 wss dto increment bits. review wss section for more details. xdssel[3:0] bits [7:4]?5e line position of extended data services (xds) content. controls which line contai ns extended data se rvices data. each line enable is independent of the other. 0001 = extended data serv ices on line 282 (525-line ) and line 333 (625-line). 0010 = extended data serv ices on line 283 (525-line ) and line 334 (625-line). 0100 = extended data servic es on line 284 (525-line) and line 335 (625-line). (default) 1000 = extended data serv ices on line 285 (525-line ) and line 336 (625-line). xtl_bfo_dis bit 5?30 on power-up, a 50% duty cycle buffered output will be transmit ted at the frequency found between the xtalin and xtalou t ports from the xtl_bfo pin #3. 0 = enable buffer crystal clock output. [default] 1 = disable buffer cr ystal clock output. xtal_pad_dis bit 6?30 0 = norm al operation. (default) 1 = disable xtalin and xtalout crystal pin. encoder must receive main clock through clki pin. table 2-5. programming detail for all read/write registers (15 of 16) bit/register names bit location bit/register definition
2.0 internal registers CX25870/871 2.4 reading registers flicker-free video encoder with ultrascale technology 2-24 conexant 100381b y_altff[1:0] bits [1:0]?34 luma alternate flicker filter selection. this bit will only have an effect when adpt_ff is set. y_altff should always be programmed to a value greater than or equal to f_sely. 00 = 5 line (default) 01 = 2 line 10 = 3 line 11 = 4 line y_off[7:0] bits [7:0]?5a brightness c ontrol. this is the luminance level of fset. expressed as a 2?s complement number. (default = 0x00) the luminance level offset is referenced from black, and can be adjusted from -22.31 ire (below black) to +22.14 ire (above black). active video will be added to the offset level. y_off is a two?s comple ment number, such that 0x00 = 0 ire offset 0x7 is +22.14 ire offset and 0x8 is -22.31 ire offset. 1 lsb =1.25 mv or .175 ire of adjustment. y_thresh[2:0] bits [2:0]?36 controls the sensitivity or limit of turning on the alternate flicker filter for luma in adaptive flicker filter mode. (default = 000) yattenuate[2:0] bits {2:0]?ca works in c onjunction with register my for contrast control. thi s bit field is for luma attenuation in discrete steps. 000 = 1.0 gain (no attenuation) (default) 001 = 15/16 gain 010 = 7/8 gain 011 = 3/4 gain 100 = 1/2 gain 101 = 1/4 gain 110 = 1/8 gain 111 = 0 gain (force luma to 0) ycoring[2:0] bits [5:3]?ca lu ma coring. values below the ycoring[2:0] limits that follow are automatically clamped to pure black by the encoder. 000 = bypass (default) 001 = 1/128 of range 010 = 1/64 of range 011 = 1/32 of range 100 = 1/16 of range 101 = 1/8 of range 110 = 1/4 of range 111 = reserved ylpf[1:0] bits [5:4]?96 luma post-flicker filter/scaler horizontal low pass filter: 00 = bypass (default) 01 = luma horizontal lpf1 setting 10 = luma horizontal lpf2 setting 11 = luma horizontal lpf3 setting yselect bit 6?36 this bit will only have an effect when adpt_ff is set. 0 = use the c_thresh value to determine the threshold for turning on the alternate flicker filter setting for chrominance. (default) 1 = use the y_thresh value to determine the threshold for turning on the alternate flicker filter setting for chrominance. both chroma and luma digital data is automatically processed with their alternate flicker filter settings when the y_thresh limit is exceeded. table 2-5. programming detail for all read/write registers (16 of 16) bit/register names bit location bit/register definition
100381b conexant 3-1 3 3.0 pc board considerations for optimum performance of the CX25870/ 871, proper cmos layout techniques should be studied before pc board layout is begun. the layout should be optimized for lowest noise on the power and ground planes by providing good decoupling. the trace length between groups of vaa (or vdd) and gnd (or vss) pins should be as short as possible to minimize inductive ringing. a well-designed power distribution networ k is critical to eliminating digital switching noise. the ground plane must pr ovide a low-impedance return path for the digital circuits. a pc board with a minimum of four laye rs is recommended, with layers 1 (top) and 4 (bottom) for signals, and layers 2 and 3 for ground and power, respectively. 3.1 component placement components should be placed as close as possible to the associated pin in order for traces to be connected point to point. the optimum layout places the CX25870/871 as close as possible to the power supply connector and the video output connector, as illustrated in figure 3-1 . some other pc board layout tips to follow are: include a silk screen layer of labels in your layout artwork showing each component and its referenc e designation. label numbered test nodes and the correct polarity of diodes and electrolytic capacitors. leave adequate space around compon ents so esd transients only have minimally adverse effects on ics. make sure signals that need access fo r troubleshooting or analysis are easy to find and probe.
3.0 pc board considerations CX25870/871 3.2 power and ground planes flicker-free video encoder with ultrascale technology 3-2 conexant 100381b 3.2 power and ground planes for optimum performance, a common digital and analog ground plane and a common digital and analog power plan e are recommended. the power plane should provide power to all CX25870/871 power pins, reference voltage (vref) circuitry, and comp decoupling. the CX25870/871 power plane should be connected to the graphics system power plane (vcc) at a single point through a ferrite bead, as illustrated in figures 3-1 and 3-2 . this bead should be located within 3 inches of the CX25870/871. the bead provides resistance to switching currents by acting as a resistor at high frequencies. a low-resi stance bead should be used, such as ferroxcube 5659065-3b, fair-rite 2723021447, or tdk bf45-4001. see table 3-1 for a typical parts list for key passive components. figure 3-1. power plane illustration CX25870 conexant (bt835) video decoder analog oscillator 3.3 vaa-cx870 o vcc3.3 ferrite bead clocks 5v 3.3 v o vcc3.3 data pci or agp connector bracket composite #1 luma chrome composite #2 s-video 4 layer board plane order: signals gnd pwr signals bottom top 100381_017
CX25870/871 3.0 pc board considerations flicker-free video encoder with ultrascale technology 3.2 power and ground planes 100381b conexant 3-3 figure 3-2. connection diagram for output filters and other key passive components/standard definition tv out only 100381_018a note(s): (1) vddl vdd_co, vdd_vref must be tied to 3.3 v CX25870/871 power plane unless interface to low power graphics controller is required. (2) depending on the parasitic capacitance of your pcb and loading expectations of your crystals, these capacitor values may change slightly. generally, the 27 pf and 33 pf combination matches a 20 pf internal xtal load. (3) no rf modulator has been included on any of the dac outputs. baseband video is always generated by the CX25870. vaa xtalin 13.500 mhz xtal xtalout comp vbias vddl (1) vdd_co (1) vdd_vref (1) vref gnd c7 c8 c2?c6 fsadjust +1.1 v to +1.8 v rset = 75 ? , 1% daca dacb CX25870/871 power plane to video connector ground (power supply connector) +3.3 v (vcc) vaa schottky diodes schottky diodes sd lpf CX25870/871 c10 + c1 fb sd lpf sd lpf sd lpf 22 pf, 5% 1.8 h, 5% 270 pf, 5% 330 pf, 5% gnd to filter dac output 27 pf (2) , 5% 33 pf (2) , 5% 75 ?, 1% 75 ?, 1% 75 ?, 1% 75 ?, 1% 10 k ? 1% 10 k ? 1% c9 p p dacc dacd p p p : sd lpf
3.0 pc board considerations CX25870/871 3.2 power and ground planes flicker-free video encoder with ultrascale technology 3-4 conexant 100381b figure 3-3. connection diagram for output filters and other key passive components/standard and hdtv out 100381_084 CX25870/871 dac d cvbs = composite #2 vaa 3.3 v 1 2 3 1 2 3 d9 bat54s sot-23 5443r10-004 r11 75.0 ? 0805 1% sd filter hd filter hd filter hd filter c21 270 pf 0805 5% 22 pf 0805 5% c22 330 pf 0805 5% l1 1.8 h 1210 5% dac b y = luma or hd y vaa 3.3 v 1 2 3 1 2 3 d7 bat54s sot-23 5443r10-004 r2 75.0 ? 0805 1% c9 62 pf 0805 5% c8 33 pf 0805 5% c10 75 pf 0805 5% bout l1 0.27 h 1210 5% dac c c = chroma or hd pr vaa 3.3 v 1 2 3 1 2 3 d8 bat54s sot-23 5443r10-004 r7 75.0 ? 0805 1% c9 62 pf 0805 5% c8 33 pf 0805 5% c10 75 pf 0805 5% cout l1 0.27 h 1210 5% dac a cvbs = composite #1 or hd pb vaa 3.3 v 1 2 3 1 2 3 d9 bat54s sot-23 5443r10-004 r11 75.0 ? 0805 1% c9 62 pf 0805 5% c8 33 pf 0805 5% c10 75 pf 0805 5% dout l1 0.27 h 1210 5% note(s): 1. hd filter imparts a passband of dc to 30 mhz. 2. sd filter imparts a passband of dc to 8 mhz.
CX25870/871 3.0 pc board considerations flicker-free video encoder with ultrascale technology 3.2 power and ground planes 100381b conexant 3-5 table 3-1. typical parts list for key passive components location description vendor part number c1?c7, c9 0.1 f ceramic capaci tor erie rpe112z5u104m50v , or equivalent c8 1.0 f ceramic capacitor erie rpe11224u104m5v, or equivalent c10 47 f capacitor mallory csr13f476km, or equivalent fb ferrite bea d?surface mount fair-rite 2743021447 rset 75 ? , 1% metal film resistor dale cmf-55c, many others trap ceramic resonator murata tpsx .xmj or mb2 (where x.x = sound carrier frequency in mhz) ? schottky diodes bat85 (bat54f dual) hp 5082-2305 (1n6263) siemens bat 64-04 (dual) xtal 13.5000 mhz fundamental , parallel resonant, 20 pf load, crystal oscillator with 25 ppm total tole rance over 0 c ? 70 c range. see appendix b note(s): vendor numbers are listed only as a guide . substitution of devices with simi lar characteristics will not affect CX25870/871 performance.
3.0 pc board considerations CX25870/871 3.2 power and ground planes flicker-free video encoder with ultrascale technology 3-6 conexant 100381b l1 1.8uh 1210 5% j4 rca jack2 2 1 3 c20 1.0 uf 0805 d2 da204k sot-23 2 3 1 10k ohm 0805 r9 l4 1.8uh 1210 5% c19 22 pf 0805 5% j1 rca jack2 2 1 3 c21 270 pf 0805 5% r11 75.0 ohm 0805 1% c22 330 pf 0805 5% c8 22 pf 0805 5% c9 270 pf 0805 5% d3 da204k sot-23 2 3 1 10k 0805 r3 10k 0805 r4 10k 0805 r5 j2 rca jack2 2 1 3 10k ohm 0805 r6 d4 da204k sot-23 2 3 1 j3 rca jack2 2 1 3 75 ohm, 1% 0805 1% r8 y1 13.500 mhz hc49u d1 da204k sot-23 2 3 1 c23 27 pf 0805 c24 33 pf 0805 r1 75.0 ohm 0805 1% r12 33 ohm 0805 c10 330 pf 0805 5% l2 1.8uh 1210 5% c12 22 pf 0805 5% l3 1.8uh 1210 5% r14 33 ohm 0805 c13 270 pf 0805 5% c15 22 pf 0805 5% c16 270 pf 0805 5% c1 10 uf 7343 + r2 75.0 ohm 0805 1% c14 330 pf 0805 5% r7 75.0 ohm 0805 1% fb1 ferrite bead fair-rite c17 330 pf 0805 5% c11 0.1 uf 0805 vaa_daca 69 field 37 vaa_dacc 73 xtalin 63 xtalout 62 vss3 22 vss2 21 vdd 1 vaa_dacb 71 vss5 41 vss1 4 reset* 53 blank* 38 vsync* 36 hsync* 35 pal 50 slave 51 sleep 52 altaddr 48 vss4 31 sic (scl) 45 sid (sda) 44 clki 54 clko 56 vref 76 vbias 77 fsadjust 78 dacc 72 dacb 70 daca 68 comp 75 vaa_pll 59 vaa_dacd 67 dacd 66 xtl_bfo 3 vss_si 42 p[15] 24 p[14] 23 p[13] 18 p[12] 17 p[11] 16 p[10] 15 p[9] 14 p[8] 13 p[7] 12 p[6] 11 p[5] 10 p[4] 9 p[3] 8 p[2] 7 p[1] 6 p[0] 5 p[16] 25 p[17] 26 p[18] 27 p[19] 28 p[20] 29 p[21] 32 p[22] 33 p[23] 34 vss_so 43 vdd_so 46 vdd_si 47 vdd_vref 49 vss_co 55 vdd_co 57 agnd_pll 58 vdd5 60 vdd_x 61 vss_x 64 agnd_dac 65 agnd_dac 74 agnd 79 vaa_vref 80 vddl 40 vdd3 20 vdd2 19 vdd1 2 vdd4 30 vss/test 39 CX25870/871 final pinout 1/02/01 80 pqfp 10k ohm 0805 r10 c3 0.1 uf 0805 c4 0.1 uf 0805 c5 0.1 uf 0805 c6 0.1 uf 0805 c7 1.0 uf 0805 c2 0.01 uf 0805 p1 connector 1 2 3 4 5 6 7 1 4 2 3 c18 0.1 uf 0805 rn3a 33 ohm 1632 1 8 rn3c 3 6 rn3d 4 5 rn3b 2 7 rn2c 3 6 rn2d 4 5 rn2b 2 7 r15 33 ohm 0805 rn1c 3 6 rn1d 4 5 rn1b 2 7 rn2a 33 ohm 1632 1 8 rn1a 33 ohm 1632 1 8 sw dip-4 1 2 3 4 8 7 6 5 cblank vsync hsync clkin 3v_scl reset aout clkout 3v_sda dac_d bout cout cout bout dout crystal_output dac_c dac_b i2c_addr pal_ctl slave_ctl sleep dac_a field rset resistor p2 p4 p9 p10 p6 p1 p3 p11 p5 p0 p7 p8 CX25870_3.3v vaa_3.3v vcc_3.3v vaa_3.3v vaa_3.3v vaa_3.3v CX25870_3.3v CX25870_3.3v CX25870_3.3v CX25870_3.3v CX25870_3.3v hsync_bi vsync_bi cblank_bi 870_clkin 3v_sda 3v_scl reset 870field_out 870clk_out p_in7 p_in3 p_in0 p_in2 p_in1 p_in4 p_in6 p_in5 p_in11 p_in8 p_in10 p_in9 xtal_clk_output **24bit rgb multiplexed interface shown in diagram 3.3v analog supply and decoupling 2743021447 if vdd_vref = 3.3v, then the following CX25870/871 inputs must be received at 3.3v levels: clki, hsync*, vsync*, blank*, and the pixel inputs- p[0] - p[11] pal master addr x88 sleep pal normal addr x8a slave altaddr state if pin#=0 sleep state if pin#=1 CX25870 pin#: slave ntsc see chart 5% 5% **float xtl_bfo if not used c = chroma (scart = b) cvbs = composite (scart = r) y = luma (scart = g) **the type and location of each video output is selectable **resistor packs must be placed as close as possible to graphics controller=source 10% **series termination must be placed as close as possible to source=encoder **r14 must be placed as close as possible to source=encoder s-video y/c output if vdd_co & vddl = 3.3v, then the following CX25870/871 outputs will be transmitted at 3.3v levels as well: clko, hsync*, vsync*, blank*, and field. all other signals will also be at 3.3v cmos levels unless denoted otherwise. key crystal(y1) specs: - operating temperature: 0-70 degrees c - mode of operation: fundamental - load capacitance: 20pf(for the xtal shown), parallel resonant - frequency tolerance: 50 ppm total maximum for ntsc; 25 ppm total maximum for pal/secam. this includes both the frequency tolerance at 25deg.c and frequency stability over temperature(0 -70deg.c) **float field if not used **r12 must be placed as close as possible to source=data master y_delay (scart=cvbs) *if blank* pin not used, tie to 3.3v thru 10kohm resistor 100381_096 figure 3-4. CX25870/871 3.3 v recommended layout for connection with 3.3 v master device standard definition tv out only
CX25870/871 3.0 pc board considerations flicker-free video encoder with ultrascale technology 3.2 power and ground planes 100381b conexant 3-7 c10 0.1 uf 0805 c9 0.01 uf 0805 rn1a 33 ohm 1632 1 8 l1 1.8uh 1210 5% j4 rca jack2 2 1 3 c23 1.0 uf 0805 10k ohm 0805 r9 l4 1.8uh 1210 5% c22 22 pf 0805 5% j1 rca jack2 2 1 3 c24 270 pf 0805 5% r12 75.0 ohm 0805 1% c25 330 pf 0805 5% c11 22 pf 0805 5% c12 270 pf 0805 5% 10k 0805 r3 10k 0805 r4 10k 0805 r5 j2 rca jack2 2 1 3 10k ohm 0805 r6 j3 rca jack2 2 1 3 y1 13.500 mhz hc49u d1 da204k sot-23 2 3 1 c26 27 pf 0805 c27 33 pf 0805 r1 75.0 ohm 0805 1% 10k ohm 0805 r11 r13 33 ohm 0805 10k ohm 0805 r14 c13 330 pf 0805 5% l2 1.8uh 1210 5% c15 22 pf 0805 5% l3 1.8uh 1210 5% r16 33 ohm 0805 c16 270 pf 0805 5% c18 22 pf 0805 5% c19 270 pf 0805 5% c1 10 uf 7343 + r2 75.0 ohm 0805 1% c17 330 pf 0805 5% r7 75.0 ohm 0805 1% fb1 ferrite bead fair-rite c20 330 pf 0805 5% c14 0.1 uf 0805 vaa_daca 69 field 37 vaa_dacc 73 xtalin 63 xtalout 62 vss3 22 vss2 21 vdd 1 vaa_dacb 71 vss5 41 vss1 4 reset* 53 blank* 38 vsync* 36 hsync* 35 pal 50 slave 51 sleep 52 altaddr 48 vss4 31 sic (scl) 45 sid (sda) 44 clki 54 clko 56 vref 76 vbias 77 fsadjust 78 dacc 72 dacb 70 daca 68 comp 75 vaa_pll 59 vaa_dacd 67 dacd 66 xtl_bfo 3 vss_si 42 p[15] 24 p[14] 23 p[13] 18 p[12] 17 p[11] 16 p[10] 15 p[9] 14 p[8] 13 p[7] 12 p[6] 11 p[5] 10 p[4] 9 p[3] 8 p[2] 7 p[1] 6 p[0] 5 p[16] 25 p[17] 26 p[18] 27 p[19] 28 p[20] 29 p[21] 32 p[22] 33 p[23] 34 vss_so 43 vdd_so 46 vdd_si 47 vdd_vref 49 vss_co 55 vdd_co 57 agnd_pll 58 vdd5 60 vdd_x 61 vss_x 64 agnd_dac 65 agnd_dac 74 agnd 79 vaa_vref 80 vddl 40 vdd3 20 vdd2 19 vdd1 2 vdd4 30 vss/test 39 CX25870/871 final pinout 1/02/01 80 pqfp 10k ohm 0805 r10 c3 0.1 uf 0805 c4 0.1 uf 0805 c5 0.1 uf 0805 c6 0.1 uf 0805 c7 1.0 uf 0805 rn3a 33 ohm 1632 1 8 75 ohm, 1% 0805 r8 rn3b 2 7 rn3c 3 6 rn3d 4 5 c2 0.01 uf 0805 rn2c 3 6 p1 connector 1 2 3 4 5 6 7 1 4 2 3 c21 0.1 uf 0805 rn2b 2 7 rn2d 4 5 d2 da204k sot-23 2 3 1 d3 da204k sot-23 2 3 1 rn1c 3 6 rn1d 4 5 d4 da204k sot-23 2 3 1 rn1b 2 7 r17 33 ohm 0805 sw dip-4 1 2 3 4 8 7 6 5 c8 10 uf 7343 + fb2 ferrite bead fair-rite rn2a 33 ohm 1632 1 8 aout bout cout cout bout dout field p8 p10 sleep p11 clkout pal_ctl p3 clkin p4 p7 p9 crystal_output p5 rset resistor 3v_scl p2 dac_d hsync reset p0 i2c_addr vsync dac_c dac_b 3v_sda slave_ctl cblank p1 p6 dac_a CX25870_3.3v vaa_3.3v vcc_3.3v vcc_1.8v vaa_3.3v vaa_3.3v vaa_3.3v CX25870_3.3v CX25870_3.3v cx870_1.8v CX25870_1.8v CX25870_3.3v hsync_bi vsync_bi cblank_bi 870_clkin 3v_sda 3v_scl reset 870field_out 870clk_out p_in7 p_in3 p_in0 p_in2 p_in1 p_in4 p_in6 p_in5 p_in11 p_in8 p_in10 p_in9 xtal_clk_output c = chroma (scart = b) cvbs = composite (scart = r) y = luma (scart = g) **24bit rgb multiplexed interface shown in diagram 3.3v analog supply and decoupling 2743021447 s-video y/c output if vdd_vref = 1.8v / 2, then the following CX25870/871 inputs must be received at 1.8v levels: clki, hsync*, vsync*, blank*, and the pixel inputs- p[0] - p[11] 1.8v analog supply and decoupling 2743021447 y_delay (scart=cvbs) pal master addr x88 sleep pal normal addr x8a slave altaddr state if pin#=0 sleep state if pin#=1 CX25870 pin#: slave ntsc see chart 5% 5% key crystal(y1) specs: - operating temperature: 0-70 degrees c - mode of operation: fundamental - load capacitance: 20pf(for the xtal shown), parallel resonant - frequency tolerance: 50 ppm total maximum for ntsc; 25 ppm total maximum for pal/secam. this includes both the frequency tolerance at 25deg.c and frequency stability over temperature(0 -70deg.c) **float xtl_bfo if not used **the type and location of each video output is selectable 1% 1% **resistor packs should be placed as close as possible to graphics controller 10% **series termination must be placed as close as possible to source=encoder if vdd_co & vddl = 1.8v, then the following CX25870/871 outputs will be transmitted at 1.8v levels: clko, hsync*, vsync*, blank*, and field. all other signals will be at 3.3v cmos levels unless denoted otherwise. **float field pin if not used **r13 must be placed as close as possible to source=data master **r16 must be placed as close as possible to source=encoder *if blank* pin not used, tie to vddl thru 10kohm resistor 100381_097 CX25870/871 3.3v/1.8v recommended layout b 11 monday, august 13, 2001 title size document number rev date: sheet of please contact your local conexant fae with questions. if that fails, call 1-949-483-6996 for more information. figure 3-5. CX25870/871 3.3 v/1.8 v recommended layout for connection with 1.8 v master device standard definition tv out only c10 0.1 uf 0805 c9 0.01 uf 0805 rn1a 33 ohm 1632 1 8 l1 1.8uh 1210 5% j4 rca jack2 2 1 3 c23 1.0 uf 0805 10k ohm 0805 r9 l4 1.8uh 1210 5% c22 22 pf 0805 5% j1 rca jack2 2 1 3 c24 270 pf 0805 5% r12 75.0 ohm 0805 1% c25 330 pf 0805 5% c11 22 pf 0805 5% c12 270 pf 0805 5% 10k 0805 r3 10k 0805 r4 10k 0805 r5 j2 rca jack2 2 1 3 10k ohm 0805 r6 j3 rca jack2 2 1 3 y1 13.500 mhz hc49u d1 da204k sot-23 2 3 1 c26 27 pf 0805 c27 33 pf 0805 r1 75.0 ohm 0805 1% 10k ohm 0805 r11 r13 33 ohm 0805 10k ohm 0805 r14 c13 330 pf 0805 5% l2 1.8uh 1210 5% c15 22 pf 0805 5% l3 1.8uh 1210 5% r16 33 ohm 0805 c16 270 pf 0805 5% c18 22 pf 0805 5% c19 270 pf 0805 5% c1 10 uf 7343 + r2 75.0 ohm 0805 1% c17 330 pf 0805 5% r7 75.0 ohm 0805 1% fb1 ferrite bead fair-rite c20 330 pf 0805 5% c14 0.1 uf 0805 vaa_daca 69 field 37 vaa_dacc 73 xtalin 63 xtalout 62 vss3 22 vss2 21 vdd 1 vaa_dacb 71 vss5 41 vss1 4 reset* 53 blank* 38 vsync* 36 hsync* 35 pal 50 slave 51 sleep 52 altaddr 48 vss4 31 sic (scl) 45 sid (sda) 44 clki 54 clko 56 vref 76 vbias 77 fsadjust 78 dacc 72 dacb 70 daca 68 comp 75 vaa_pll 59 vaa_dacd 67 dacd 66 xtl_bfo 3 vss_si 42 p[15] 24 p[14] 23 p[13] 18 p[12] 17 p[11] 16 p[10] 15 p[9] 14 p[8] 13 p[7] 12 p[6] 11 p[5] 10 p[4] 9 p[3] 8 p[2] 7 p[1] 6 p[0] 5 p[16] 25 p[17] 26 p[18] 27 p[19] 28 p[20] 29 p[21] 32 p[22] 33 p[23] 34 vss_so 43 vdd_so 46 vdd_si 47 vdd_vref 49 vss_co 55 vdd_co 57 agnd_pll 58 vdd5 60 vdd_x 61 vss_x 64 agnd_dac 65 agnd_dac 74 agnd 79 vaa_vref 80 vddl 40 vdd3 20 vdd2 19 vdd1 2 vdd4 30 vss/test 39 CX25870/871 final pinout 1/02/01 80 pqfp 10k ohm 0805 r10 c3 0.1 uf 0805 c4 0.1 uf 0805 c5 0.1 uf 0805 c6 0.1 uf 0805 c7 1.0 uf 0805 rn3a 33 ohm 1632 1 8 75 ohm, 1% 0805 r8 rn3b 2 7 rn3c 3 6 rn3d 4 5 c2 0.01 uf 0805 rn2c 3 6 p1 connector 1 2 3 4 5 6 7 1 4 2 3 c21 0.1 uf 0805 rn2b 2 7 rn2d 4 5 d2 da204k sot-23 2 3 1 d3 da204k sot-23 2 3 1 rn1c 3 6 rn1d 4 5 d4 da204k sot-23 2 3 1 rn1b 2 7 r17 33 ohm 0805 sw dip-4 1 2 3 4 8 7 6 5 c8 10 uf 7343 + fb2 ferrite bead fair-rite rn2a 33 ohm 1632 1 8 aout bout cout cout bout dout field p8 p10 sleep p11 clkout pal_ctl p3 clkin p4 p7 p9 crystal_output p5 rset resistor 3v_scl p2 dac_d hsync reset p0 i2c_addr vsync dac_c dac_b 3v_sda slave_ctl cblank p1 p6 dac_a CX25870_3.3v vaa_3.3v vcc_3.3v vcc_1.8v vaa_3.3v vaa_3.3v vaa_3.3v CX25870_3.3v CX25870_3.3v cx870_1.8v CX25870_1.8v CX25870_3.3v hsync_bi vsync_bi cblank_bi 870_clkin 3v_sda 3v_scl reset 870field_out 870clk_out p_in7 p_in3 p_in0 p_in2 p_in1 p_in4 p_in6 p_in5 p_in11 p_in8 p_in10 p_in9 xtal_clk_output c = chroma (scart = b) cvbs = composite (scart = r) y = luma (scart = g) **24bit rgb multiplexed interface shown in diagram 3.3v analog supply and decoupling 2743021447 s-video y/c output if vdd_vref = 1.8v / 2, then the following CX25870/871 inputs must be received at 1.8v levels: clki, hsync*, vsync*, blank*, and the pixel inputs- p[0] - p[11] 1.8v analog supply and decoupling 2743021447 y_delay (scart=cvbs) pal master addr x88 sleep pal normal addr x8a slave altaddr state if pin#=0 sleep state if pin#=1 CX25870 pin#: slave ntsc see chart 5% 5% key crystal(y1) specs: - operating temperature: 0-70 degrees c - mode of operation: fundamental - load capacitance: 20pf(for the xtal shown), parallel resonant - frequency tolerance: 50 ppm total maximum for ntsc; 25 ppm total maximum for pal/secam. this includes both the frequency tolerance at 25deg.c and frequency stability over temperature(0 -70deg.c) **float xtl_bfo if not used **the type and location of each video output is selectable 1% 1% **resistor packs should be placed as close as possible to graphics controller 10% **series termination must be placed as close as possible to source=encoder if vdd_co & vddl = 1.8v, then the following CX25870/871 outputs will be transmitted at 1.8v levels: clko, hsync*, vsync*, blank*, and field. all other signals will be at 3.3v cmos levels unless denoted otherwise. **float field pin if not used **r13 must be placed as close as possible to source=data master **r16 must be placed as close as possible to source=encoder *if blank* pin not used, tie to vddl thru 10kohm resistor 100381_097 CX25870/871 3.3v/1.8v recommended layout b 11 monday, august 13, 2001 title size document number rev date: sheet of please contact your local conexant fae with questions. if that fails, call 1-949-483-6996 for more information.
3.0 pc board considerations CX25870/871 3.3 recommended schematics and layout for CX25870/871 flicker-free video encoder with ultrascale technology 3-8 conexant 100381b 3.3 recommended schema tics and layout for CX25870/871 for the CX25870/871 to operate at an optimal technical level, it is imperative to adopt the passive components, values, tole rances, and guidelines contained in the following figures. conexant has done extensive lab test ing with these components, and found that they yield the best combin ation of performance and price. the complete schematic diagram for a 3.3 v only design is illustrated in figure 3-4 . the complete schematic diagram fo r a mixed 3.3 v and 1.8 v design environment is illustrated in figure 3-5 . for a complete schematic diagram for a mixed 3.3v and lower voltage (1.5 v or 1.1 v) design environment, request assistance from your local fae. the finished schematic for the 3.3 v/1.5 v or 3.3 v/1.1 v case will look similar to figure 3-5 . substitution of resistors, capacito rs, inductors, and crystals with nonrecommended values or greater than recommended tolerances may degrade the video output quality of the CX25870/871 encoder.
CX25870/871 3.0 pc board considerations flicker-free video encoder with ultrascale technology 3.4 decoupling 100381b conexant 3-9 3.4 decoupling 3.4.1 device decoupling for optimum performance, all capacitors should be located as close as possible to the device, and the shortest possible lead s (consistent with re liable operation) should be used to reduce the lead indu ctance. chip capacitors are recommended for minimum lead inductance. radial lead ceramic capacitors can be substituted for chip capacitors and are better than axial lead capacitors for self-resonance. values are chosen to have self-resonance above the pixel clock. 3.4.2 power supply decoupling the best power supply performance is obtained with a 0.1 f ceramic capacitor decoupling each group of vaa pins and each group of vdd pins to gnd. the capacitors should be placed as close as possible to the device vaa/vdd pins and gnd pins and connected with short, wide traces. the 47 f capacitor shown in figure 3-2 is for low-frequency power supply ripple; the 0.1 f capacitors are for high-frequency power supply noise rejection. inclusion of a 0.01 f and a 1.0 f capacitor between the group of vaa/vdd pins and gnd/vss pins will improve power supply decoupling at intermediate frequencies as well. when a linear regulator is used, the proper power-up sequence must be verified to prevent latchup. a linear regulator is recommended to filter the analog power supply if the power supply noise is greater than or equal to 200 mv. this is especially important when a switching power supply is used, or low voltage interface is implemented, and the switching frequency is close to the raster scan frequency. about 5 percent of the power supply hum and ripple noise less than 1 mhz will couple onto the analog outputs. 3.4.3 comp decoupling the comp pin must be decoupled to the closest vaa pin, typically with a 0.1 f ceramic capacitor. low-frequency supply noise will require a larger value. the comp capacitor must be as close as possible to the comp and vaa pins. a surface-mount ceramic chip capacitor is preferred for minimal lead inductance. lead inductance degrades the noise rejectio n of the circuit. short, wide traces will also reduce lead inductance. 3.4.4 vref decoupling a 1.0 f ceramic capacitor should be used to decouple this input to gnd. 3.4.5 vbias decoupling a 0.1 f ceramic capacitor should be used to decouple this output to gnd.
3.0 pc board considerations CX25870/871 3.5 signal interconnect flicker-free video encoder with ultrascale technology 3-10 conexant 100381b 3.5 signal interconnect 3.5.1 digital si gnal interconnect the digital inputs to the CX25870/871 should be isolated as much as possible from the analog outputs and other analog circuitry. also, these input signals should not overlay the analog powe r plane or analog output signals. most of the noise on the analog outputs will be caused by fast transitioning clock edges, data edges (less than 3 ns), and overshoot, undershoot, and ringing on the digital inputs. the digital edge rates should not be fa ster than necessary because feedthrough noise is proportional to the digital edge rates. lower-speed applications will benefit from using lower-speed logic (3?5 ns edge rates) to reduce data-related noise on the analog outputs. transmission lines will mismatch if the lines do not match the source and destination impedance. this will degrad e signal fidelity if the line length reflection time is greater than one-fourth the signal edge time. line termination or line-length reduction is the solution. for example, logic edge rates of 2 ns require line lengths of less than 4 inches without use of te rmination. ringing can be reduced by damping the line with a series resi stor (30?50 ? ). radiation of digital signals can also be picked up by the analog circuitry. this is prevented by reducing the digital edge rates (rise/fall time), minimizing ringing with damping resistors, an d minimizing coupling thro ugh pc board capacitance by routing the digital signals at a 90 -degree angle to any analog signals. the clock driver and all other digital devices must be adequately decoupled to prevent noise generated by the digital devices from coupling into the analog circuitry. 3.5.2 analog signal interconnect the CX25870/871 analog output traces shou ld be located as close as possible to the output connectors and be of equal length to minimize noise pickup and reflections caused by impedance mismatch. the analog outputs are susceptible to crosstalk from digi tal lines; therefore digital traces must not be routed under or adjacent to the analog output traces. to maximize the high-frequency power supply rejection, the video output signals should overlay the ground plane. for maximum performance, the analog video output impedance, cable impedance, and load impedance should be the same. the load resistor connection between the video outputs and gnd should be as close as possible to the CX25870/871 to minimize reflections. unus ed dac analog outputs should be left floating.
CX25870/871 3.0 pc board considerations flicker-free video encoder with ultrascale technology 3.6 applications information 100381b conexant 3-11 3.6 applications information 3.6.1 changes required to accommo date CX25870/871 in bt868/869-designs 3.6.1.1 software the CX25870/871 is software backward compatible with conexant?s first generation vga encoder, the bt868/869. th is means that all register indices for the bt868/869 were carried forward to the exact same indices for the CX25870/871. for conexant?s second ge neration encoder, new registers were added, but the actual addr esses used were outside of the 0x6c to 0xd6 range reserved for the bt868/869 legacy functio nality. some reserved bits within the bt868/869 did take on significance with the CX25870/871 where necessary. the most significant difference in software between the two encoders is the fact that the CX25870/871 can be read fr om using the standard serial method as well as the legacy serial method. to use the standard pro cedure, the master issues CX25870?s device id and subaddress in consecutive bytes, and the slave acknowledges with a pulse after each tr ansaction. upon completion of these 2 steps, the slave transmits the final byte which contains the 8 bits of data. the bt868/869 cannot be read from in this manner and instead relies solely on the legacy method. this process is explaine d step-by-step in th e ?tv auto-detection procedures? section of this specification. another difference in terms of software between the two encoders is the power-up video output routing. the CX25870 after power-up or a signal-driven reset transmits video0 = composite on dac_a, video1 = luma (y) on dac_b, video2 = chroma (c) on dac_c, and video3 = luma delay on dac_d. the bt868 was different in this respect. on power-up, it sent out video0 = composite from dac_a, dac_b, and dac_c. reprogramming register 0xce correctly ensures proper video output routing. table 3-2. relative register map for CX25870/871 shared CX25870/871 & bt868/869 registers register addresses 0x 00 to 0x04 (read only) (must be accessed through ?leg acy? read procedure with es tatus[1:0] bits in bt868/869) (?standard? or ?legacy? read-b ack procedure ok for CX25870/871) CX25870/871 specific registers register address 0x06(read only) and register addresses 0x2 8e to 0x6a (read/write) shared CX25870/871 & bt868/869 registers register address 0x6c(read/write) to register address 0xd6(read/write) CX25870/871 specific register register address 0xd8(read/write)
3.0 pc board considerations CX25870/871 3.6 applications information flicker-free video encoder with ultrascale technology 3-12 conexant 100381b another difference between the two enco ders is the default video output routing through the on-chip dacs. on power-up, the bt868 transmitted video[0] = composite from all three of its dacs. du e to the popularity of s-video out, the cx25871, on power-up, broadcasts video[0] = composite from dac_a, video[1] = luminance from dac_b, video[2] = chrominance from dac_c, and video[3] = delayed luminance from dac_d. for bt868 drivers that did not program register 0xce, this step may be necessary to re-route the video outputs with the CX25870. as a result of software register compa tibility, no modificatio ns to a customer?s source code are required to enable the same features that exist within both conexant vga encoders. of course, to exploit the new features within the CX25870/871, such as display of 1024x768 resolution on a tv, hdtv output, secam output, and others, some software changes and new register sets will be necessary. this usually equates to the re lease of a new driver and/or graphics bios for support of the CX25870. 3.6.1.2 hardware similarly, the bt868/869 is pin-for-pin backward compatible with the newest conexant encoder. both devices are hous ed in exactly the same compact 80-pin, [14 mm x 14 mm x 2.4 mm] plastic pqfp package. furthermore, aside from pins 2, 3, 65, 66, and 67, which were no connects within the bt868/869, the CX25870/871 is identical in its pinout to the previous generation. consequently, if the customer?s bt868-designed pcb actually has no connects for the pins listed as n/c on the bt868/ 869, then no pc board changes are needed except for some passive co mponent stuffing changes when upgrading to the CX25870/871. however, if the bt868/869 n/c pins were actually grounded or utilization of the new extern al features within the CX25870/871 is desired, then a few changes to a customer?s bt868/869-based pc board are definitely required to accommodate the new CX25870/871. table 3-3 summarizes all the likely alterations that need to be performed to existing designs. table 3-3. hardware modifications to bt868/869-bas ed pcb required to accommodate the CX25870/871 (1 of 3) pin # bt868/9 pin name CX25870/1 pin name comment 1 agnd vdd this pin should be tied to vdd (3.3v) for both the CX25870/1 and bt868/9, so the encoder?s output video levels match the ire levels that it was designed to transmit. conexant has seen 2-3 ire ex cursions away from the corre ct color bar and other test pattern ire levels and ha ve verified that either encoder' s pin #1 being tied to gnd to be the root cause. an output video difference of 2-3 ire is a very small amplitude and would only be noticeable if you used a vm700t from tektroni x or some other advanced piece of video measuring equipment. vi sually, it is quite difficult to even detect a 2-3 ire excursion. in conclusion, tie pin #1 which was the bt 868/9?s ?agnd? to vdd/vaa = 3.3v for both the CX25870/1 and bt868/9 for best operati on. rename this pin (#1) on any schematics so it says 'vdd.? 2 n/c vdd the digital power pin needs to be tied to 3.3v. this was a no connect for the bt868/9. 3 n/c xtl_bfo the buffered crystal clock output pin should be floa ted if not used. this was a no connect for the bt868/9. for CX25870/1-designs, a small (e.g. 33 ohm) seri es resistor should be added in series to xtl_bfo as close as possible to the si gnal source device. this reduces overshoot and undershoot on this signa l as it cha nges states.
CX25870/871 3.0 pc board considerations flicker-free video encoder with ultrascale technology 3.6 applications information 100381b conexant 3-13 49 vddmax vdd_vref pin 49 has been re named for the CX25870/1. for 3.3v swings on the interface signals for CX25870/1-designs, this pin should be tied directly to 3.3v as was the case with bt868/9-designs. for lower voltage swings for the digital interface signals, using a voltage divider circuit or some other method, tie the CX25870/871?s vdd_vref input (pin 49) to (vddl / 2). see figure 3-5 for an illustration of this concept. 50 pal pal if the desired video output at power-up is pal, then a 10 k ? pull-up resistor is recommended for this pin for CX25870/1-de signs. no pull-up resistor was advocated for bt868/9-designs. if the desired video out put at power-up is ntsc, then this pin should be tied directly to gnd. 51 slave slave if desired interface at power-up is slav e or pseudo-master (i.e. slave video timing), then a 10 k ? pull-up resistor is recommended for this pin for CX25870/1-designs. no pull-up resistor was advocated for bt868/9-des igns. if desired interface at power-up is master (i.e. mast er video timing), then this pin should be tied directly to gnd. 52 sleep sleep if desired power manage ment state at power-up is norm al operation, then this pin should be tied directly to gnd. if desired power mana gement state at power-up is sleep, then a 10 k ? pull-up resistor is recommended for this pin for CX25870/1-designs. no pull-up resistor was advocated fo r bt868/9-designs. 62 63 xtalout xtalin xtalout xtalin the recommended capacitor value from xtalin to gnd has been altered from 33 pf to 27 pf for a 20 pf load crystal. this ensure s an output-to-input voltage gain sufficient to make up signal losses through the crystal since the ratio of c xtalout / c xtalin = 1.1 to 1.5. the buffered clock crystal output frequenc y, which can be measured from the CX25870/1's xtl_bfo output port, should be wi thin 25 ppm = +/- 337 hz. of 13.5000 mhz. at all times. the hi gh amount of tolerance is ne cessary so the encoder can generate sufficient accuracy for the subcarrier fre quencies for secam, pal, and ntsc. if this type of accuracy does not exist when using c xtalin = 27 pf then c xtalin should be increased to 30 pf or 33 pf and the frequency re-measu red. different pcbs exhibit different amounts of parasitic capacitance so one value for c xtalin does not necessarily fit for all designs. for bt868/9-designs, c xtalin and c xtalout were recommended to be equal (33 pf). the 1 m ? resistor, a requirement of bt868/9-designs as an external passive between these 2 pins, is no longer necessary with CX25870/ 1-designs. if it is present, then this has no adverse effects on the cx 25870/1?s overall video performance. 65 n/c agnd_dac whether or not dacd is actually used as a video output within the CX25870/1 design, this pin must be tied to gnd. for bt868/9-based desi gns, this pin was a no connect and for best performance should be tied to gnd or left open. 66 n/c dacd pin 66 for the CX25870/1 is the fourth dac = dacd. if dacd is used, connect this output to a video connector. if dacd is not used, leave this pin no connected for cx2587 0/1-designs. the circuitry for the low pass filter for dacd will also need to be added for CX25870/1 designs. for bt868/9-based desi gns, this pin was a no connect and for best performance should be tied to gnd or left open. 67 n/c vaa_dacd this is the power pin for dacd. whet her or not dacd is actu ally used within the design, this pin must be tied to vdd=vaa=3.3v for all CX25870/1-designs. for bt868/9-based desi gns, this pin was a no connect and for best performance should be tied to gnd or left open. table 3-3. hardware modifications to bt868/869-bas ed pcb required to accommodate the CX25870/871 (2 of 3)
3.0 pc board considerations CX25870/871 3.6 applications information flicker-free video encoder with ultrascale technology 3-14 conexant 100381b to ensure proper operation of the cx25 870/871, the designer must adhere to each recommendation contained in table 3-3 . 75 comp comp a 0-10 ohm resist or between comp and 0.1 f capacitor (which is connected to vaa) was originally recommende d for bt868/9-designs. the 0-10 ohm resistor placed between the 0.1 f cap and the comp pin was recommended to better tune the comp circ uit to prevent an internal op-amp from oscillating. based on the bt 868/9's dac performance over time and the CX25870/1's continued usage of th ese same dacs, this resistor was deemed to not be necessary and should be removed for all CX25870/1 designs. 76 vref vref capacitor from vr ef to gnd must be 1.0 f for the CX25870/1. capacitor from vref to gnd must be 0.1 f for the bt868/9. 78 fsadjust fsadjust rset, the resistor from fsadjust pi n to gnd, must be 75 ? , +/- 1% for all CX25870/1-based designs. rset must be 100 ohm , +/- 1% for all bt868/9-based designs. note(s): n/c = no connect table 3-3. hardware modifications to bt868/869-bas ed pcb required to accommodate the CX25870/871 (3 of 3)
CX25870/871 3.0 pc board considerations flicker-free video encoder with ultrascale technology 3.6 applications information 100381b conexant 3-15 3.6.2 programmable vide o adjustment controls the quality of the tv out picture can be altered depe nding on the digital input content, the settings of various output vi deo adjustment control registers, and the tv itself. the values of the cx25 870/871?s y_off, my, y_atten, mcb, mcr, c_atten, and phase_off registers all definitely impact the perceived quality of the analog ntsc/pal/secam video signal. for this reason, for graphics cards that utilize the encoder, conexant reco mmends the inclusion of a graphical user interface (gui) for tv out. by designing this intelligent control panel, the end-user can improve his tv image quality by adjusting the proper slider or other controls at his disposal. behind these controls, intelligence must be embedded in the tv out source code and dr iver so the values of certain registers get adjusted depending on the status of the radio button, checkbox, slider, or pulldown menu. an illustration of a sample gui for tv out is shown in figure 3-6 . figure 3-6. conexant recommended tv out gui for CX25870/871 100381_101
3.0 pc board considerations CX25870/871 3.6 applications information flicker-free video encoder with ultrascale technology 3-16 conexant 100381b 3.6.2.1 contrast contrast is a video quality that refers to how far the whitest whites are from the blackest blacks in an analog video wavefo rm. if the peak white is far away from the peak black, the image is said to have high contrast. with high contrast, the image is very pure like a black and white tile floor. if the two parameters are very close together, the image is said to have poor, or low, contrast. with low amounts of contrast, an image may be referred to as being washed-out. instead of easily recognized black portions of the image versus white parts, the image with low contrast looks gray. register my[7:0] in conjunction with register y_attenuate[2:0] controls adjustment of contrast. y_attenuate has 8 possible values ranging from 1.0 gain (no attenuation) to 0 gain (force luminance to 0). conexant recommends inclusion of an 8-level slider to control the contrast level. each single movement of the slider should reprogram this bit field to a different fractional value. lab testing has shown that values from ? ga in (y_attenuate=011) to 15/16 gain (i.e., 001) yield the crispest tv picture. register my modifies the luminance multiplier allowing for a larger or smaller luminance range. for more drastic changes in the contrast, change my. for more subtle changes, sh ifting the y_off register as the end-user moves the slider should be sufficient. since the difference between contrast and brightness is usually understood by video professionals only, conexant recommends the designer increment or decrement the yattenuate[2:0] field fo r either brightne ss or contrast adjustments. 3.6.2.2 saturation saturation is the amount of color present. for example, a lightly saturated green looks olive-green to gray while a fully saturated green looks like the color of a pine tree. saturation does not mean the brightness of a color, just how much pigment is used to make the color itself . the less pigment, the less saturated the color is, effectively adding white to the pure color. the amount of saturation is co ntrolled by the bit field named cattenuate[2:0]. cattenuate has eigh t possible values ranging from 1.0 gain (no attenuation) to 0 gain (force chrominance to 0). conexant recommends inclusion of an 8-level slider to control sa turation level. each single movement of the slider should reprogram this bit fiel d to a different fractional value. lab testing has shown that values from ? ga in (cattenuate=011) to 1.0 gain (i.e., 000) yield the crispest tv picture. 3.6.2.3 brightness brightness is defined to be the intensity of the video level and refers to how much light is emitted from the display. the amou nt of brightness is controlled by the register named y_off[7:0]. y_off[7:0] is a 2s complement number, such that a value of 0x00 is 0 ire offset, a value of 0x7f is an increase of 22.14 ire above black level. active video will then be added to the offs et level set by the y_off value. since the difference between contrast and brightness is usually understood by video professionals only, conexant recommends the designer increment or decrement the yattenuate[2:0] field fo r either brightne ss or contrast adjustments.
CX25870/871 3.0 pc board considerations flicker-free video encoder with ultrascale technology 3.6 applications information 100381b conexant 3-17 3.6.2.4 hue hue refers to the wavelength of the color. that means that hue is the term used to represent the base color?red, green, ma genta, yellow, and so forth. hue is completely separate from the intensity or the saturation of the color. for example, a red hue could look brown at low saturation, fire-engine red at a higher level of saturation, or pink at a high brightness level. all three colors have the same hue however. occasionally, the end user may need to alter the hue. the me thod for adjusting this parameter with the CX25870/871 is to program a different value to the hue_adj register. this method changes the hue in the composite and s-video signals for ntsc, pal, and secam wa veforms according to the following equation: desired phase offset (in degrees) = [360 / 256] * (hue_adj) a slider labeled ?hue? should be incl uded in the gui so minor alterations (20 ) in this parameter are possible. major alterations(>20 ) in the phase offset are not recommended since dramatic hue shif ts will result in different colors than the original. 3.6.2.5 sharpness occasionally, drastic phase shifts occur at the borders of dialog boxes within applications programs and with certain combinations of text and background colors. this is due to the primary and secondary colors being at opposite ends of the uv hue spectrum. the result of these phase differences is that the edges or text look blurry to the observer. the CX25870/871 has a bit field available named pkfil_sel[1:0] to sharpen these edges so they look crispe r on the television. four choices are available, each of which enables a different type of peaking filter. the 0 db (bypass) filter is the defaulted level while gains of 1 db, 2 db, and 3.5 db are also possible. 3.6.2.6 dot crawl dot crawl refers to a specific image arti fact that is the result of the ntsc standard. when some computer generated text shows up on top of a video clip being shown, close viewing of the tv will show some pixels or jaggies rolling up or down the picture in the area of a dialog box?s edges. another term for this phenomenon is creepy-crawlies or the zipper effect. conexant has derived software code to minimize the dot crawl. this is not a register or bit within the CX25870/871 but rather a complicated software algorithm that modifies the 90-degree co lor subcarrier shift exhibited in four consecutive ntsc fields. to obtain this code, file a request with your local conexant sales office. the algorithm/func tion for dot crawl should be enabled with the ntsc composite output only. it will have no effect for pal or secam outputs.
3.0 pc board considerations CX25870/871 3.6 applications information flicker-free video encoder with ultrascale technology 3-18 conexant 100381b 3.6.2.7 standard and adaptive flicker filter flicker occurs when the refre sh rate of the video is too low. in digital encoders, flicker can also occur when processing an image that contains many fine vertical divisions such as lines that are only 1 or 2 lines wide. when the encoder stores, combines (by vertically interpolating data), and converts two consecutive incoming frames into 1 output field, port ions of the image containing just a few lines can be placed on different analog output lines. since the position of the output line is not equivalent from field to field, it appears to flicker at the vertical refresh rate. this annoying artifact can be eliminated by selecting an appropriate flicker filter setting, one that trades off vertical resolution and text cl arity against flicker reduction. the flicker filter slider shown in figure 3-6 modifies the f_sely[2:0] and f_selc[2:0] bit fields together anytime the end-us er changes the particular level. internal testing has shown that certain application programs such as spreadsheets look best with more flicker filtering whil e others, such as games and dvd movies, look best with less. in additi on, the active resolution also affects the amount of flicker filtering required. 640x 480 and lower resolutions rarely require a maximum flicker filter setting, wher eas the 1024x768 resolution often does. with five standard flicker filter levels available, conexant recommends programming the following bit values according to the slider level. note: the optimal performance for the stan dard flicker filter is usually achieved by configuring f_selc to 1 line less than f_sely. the CX25870/871 also has an adaptive flicker filter (i.e., adaptive ff). this feature is explained in section 1 of th e data sheet. the recommended tv out graphical user interface allows the usage of the adaptive flicker filter only if the box to enable it is checked. once this is done, the adpt_ff bit should get set (=1). flicker filter slider level f_sely[2:0] f_selc[2:0] level 5 = maximum 000 = 5 line. dis_ff ilt = 0. 011 = 4 line. dis_ffilt = 0. level 4 011 = 4 line. dis_ffilt = 0. 010 = 3 line. dis_ffilt = 0. level 3 010 = 3 line. dis_ffilt = 0. 001 = 2 line. dis_ffilt = 0. level 2 001 = 2 line. dis_ffilt = 0. 001 = 2 line. dis_ffilt = 0. level 1 = minimum do not care. dis_ff ilt = 1. do not care. dis_ffilt = 1.
CX25870/871 3.0 pc board considerations flicker-free video encoder with ultrascale technology 3.6 applications information 100381b conexant 3-19 table 3-4. CX25870 optimal adaptive flicker filter bit settings by active resolution adaptive flicker filter bit/bit field settings register 0x34 register 0x36 adaptive flicker filter slider level adpt ff y altff c altff y thresh c thresh y select ffrtn byycr chroma bw final hex value final hex value level 1=min=640x480 on=checked 4-line 4-line 000 000 on on 1 0 9b c0 level 2 on=checked 4-line 4-line 100 100 off off 1 0 9b 24 level 3 = 800x600 on=checked 5-line 5-line 010 010 off on 1 0 80 92 level 4 on=checked 5-line 5-line 100 100 on off 1 0 80 64 level 5=max=1024x768 on=c hecked 5-line 5-line 110 110 on on 1 0 80 f6
3.0 pc board considerations CX25870/871 3.6 applications information flicker-free video encoder with ultrascale technology 3-20 conexant 100381b when the adaptive flicker filter is on, the standard flicker filter continues to work normally. indeed, many of the lines and/or pixels will still be filtered at the more moderate standard flicker filter level. however, as the encoder analyzes and processes each pixel, it will periodically come across certain regions requiring a more aggressive filter setting. for thes e areas only, more forceful adaptive flicker filter value is used. with the dynamic ability of the CX25870, the end-user can enjoy an optimal tv out environment without having to manually adjust the amount of flicker filtering depending on his given application. the CX25870 provides this functionality so long as the adaptive flicker filter slider and control boxes are includ ed. when the adaptive el ement is turned on, an additional five flicker reduction settings can be applied by moving the control pad to another level. through testing, conexant recommen ds the following bit settings get reprogrammed according to the state of the adaptive flicker filter slider. integrating both flicker filter sliders a nd the correct intelligence behind them makes the CX25870/871 ideal for internet browsing, dvd movie watching, or game playing by overcoming many of the quality problems like image flicker, illegible text, and low-definition graphi cs that plague other tv encoders. 3.6.2.8 position there are many tv manufacturers, and most models display the active picture in a slightly different position relative to th e bezel of the television itself. to allow the end-user the ability to position the tv picture directly in the middle of his screen, or any other reasonable locati on, conexant recommends inclusion of several position control buttons. there should be four directional co ntrols included; two for horizontal adjustment and two for vertical adjustment. for practical usage, the maximum or limit adjustment amounts should be 25 pixe ls horizontally and 10 lines vertically from the default position. values greater than these cause a good portion of the active region to be hidden behind the bezel of the tv thus rendering this area useless. from experience, conexant recomme nds incrementing the graphics controller?s hsync_start register by 5 pixels every time the left(= ???) or right(= ?+?) button is clicked within the gui. every mouse click will also require reprogramming the CX25870/871?s h_blanki register so the active data does not get chopped off on the opposite side. vertically, the software driv er should add or subtract two lines from the prior vertical position every time the up(= ?+?) or down(= ???) button is clicked within the gui. this means that th e vsync_start register should be increased or decreased by two lines for ev ery vertical click by the end-user. the corresponding modification that needs to be made to the CX25870/871 is an add/subtract of two lines to the orig inal value in its v_blanki register. as an illustration, assume the end us er clicked on the right button once. internally, this action would mean that the graphics controller?s new hsync_start register value needs to be {hsync_start default ? 5 pixels}. as the timing master, this would force th e controller to issue its hsync* digital signal?s leading edge five pixel clock cycl es earlier in time. the software engineer also must add five pixels to the controller?s hsync_end register to maintain the original hsync* pulse duration (8?20 pixels is common). finally, within the CX25870/871, the h_blanki[9:0] register must be increased by five pixels so the encoder can accommodate the five extra pixels of blanking to start each line and still display the original active portion of the line.
CX25870/871 3.0 pc board considerations flicker-free video encoder with ultrascale technology 3.6 applications information 100381b conexant 3-21 now, assume the end-user clicked on the down button once. this action dictates that more blanking will exist befo re the active region is displayed. this operation requires decrem enting the graphics controller?s new vsync_start register value to (vsync_start default - 5 lines). as the timing master, this would force the controller to issue its vs ync* digital signal?s leading edge five lines earlier in time than before. the soft ware engineer must also subtract five lines to the controller?s vsync_end register to maintain the same vsync* pulse duration (nominally two-to-six lines). within the encoder, the v_blanki[7:0] register must be increm ented by 5 lines so the encoder can accommodate the five more lines of blanki ng required to start the field and still display the original active area of the frame. for an explanation of the left and up buttons, simply apply the opposite offsets to the values explained for the ri ght and down operations. remember that sync_start/end always works in the opposite direction of picture movement. if the position control works correctly, the end user should see a gradual change to ei ther the x and y position of the active image after each corresponding mouse click. 3.6.2.9 size this control pad is used by the end-user to change th e active x and y dimensions of the tv out picture. this is done by modifying the amount of horizontal (x dimension) and vertical (y dimension) overscan compensation. ideally, there should be four directional controls included: two for horizontal adjustment and two for vertical adjustment. for practical usage, the maximum amounts of horizontal overscan compensation (hoc ) and vertical over scan compensation (voc) should be limited to 25 percent (o r three mouse clicks in any direction). the minimal amounts of hoc and voc should be capped at 10 percent since percentages smaller than this often make the tv image so large that all edges are behind the bezel of the tv, rendering the outer regions of the windows desktop useless. based on testing, conexant recommends changing the hoc percentage by ~ 3 percent from its previous value for each?+ or ? horizontal mouse click within the gui. the + symbol denotes a larger pictur e size in that direction (and a decrease in the amount of horizontal blanking or hoc percent) and a - sign corresponds to smaller picture size. in addition, tv out software designers should vary the voc percentage by ~ 3 percent from its previous value for each + or ? vertical mouse click within the gui. the + symbol denotes a larger pict ure size in that direction and a ? sign corresponds to smaller picture size (and an increase in the am ount of vertical blanking or voc percent). the overscan percentages ho rizontally and vertically are independent of each other. however, the tv out picture look s best when hoc and voc are equal or within 2 percent of each other. having realized this fact, conexant has incorporated many autoconf iguration modes that have a minimal difference (i.e., delta) between the hoc and voc ratios.
3.0 pc board considerations CX25870/871 3.6 applications information flicker-free video encoder with ultrascale technology 3-22 conexant 100381b the autoconfiguration modes for the CX25870/871 that pertain to the desktop resolutions are summarized in figures 3-5 through 3-12 . figure 3-7. CX25870/871 autoconfiguration modes for 640x480 rgb in, ntsc out desktop resolutions figure 3-8. CX25870/871 autoconfiguration modes for 640x480 rgb in, pal-bdghi out desktop resolutions 100381_077 autoconfig. mode #0 13.78 % 13.58 % autoconfig. mode #32 18.34 % 19.34 % ?1 ?1 0 hoc voc 640 x 480 rgb in, ntsc out decrease horiz. (# of logical clicks) increase horiz. horizontally constant decrease vert. vertically const. increase vert. 0 +1 +1 100381_078 (# of logical clicks) autoconfig. mode #17 13.63 % 13.19 % autoconfig. mode #1 16.55 % 16.66 % autoconfig. mode #33 20.27 % 19.79 % ?1 ?1 0 hoc voc 640 x 480 rgb in, pal-bdghi out (# of logical clicks) 0 +1 +1
CX25870/871 3.0 pc board considerations flicker-free video encoder with ultrascale technology 3.6 applications information 100381b conexant 3-23 figure 3-9. CX25870/871 autoconfiguration modes for 800 x 600 rgb in, ntsc out desktop resolutions figure 3-10. CX25870/871 autoconfiguration modes for 800 x 600 rgb in, pal-bdghi out desktop resolutions 100381_079 autoconfig. mode #18 13.79 % 13.58 % autoconfig. mode #2 21.62 % 11.52 % autoconfig. mode #40 15.59 % 15.65 % autoconfig. mode #34 19.26 % 19.34 % ?1 ?1 0 hoc voc 800 x 600 rgb in, ntsc out (# of logical clicks) (# of logical clicks) 0 +1 +1 100381_080 autoconfig. mode #3 14.52 % 13.19 % autoconfig. mode #19 16.42 % 15.97 % autoconfig. mode #35 19.03 % 18.40 % ?1 ?1 0 hoc voc 800 x 600 rgb in, pal-bdghi out (# of logical clicks) (# of logical clicks) 0 +1 +1
3.0 pc board considerations CX25870/871 3.6 applications information flicker-free video encoder with ultrascale technology 3-24 conexant 100381b figure 3-11. CX25870/871 autoconfiguration modes for 1024 x 768 rgb in, ntsc out desktop resolutions figure 3-12. CX25870/871 autoconfiguration modes for 1024 x 768 rgb in, pal-bdghi out desktop resolutions 100381_081 autoconfig. mode #26 11.97 % 11.93 % autoconfig. mode #10 15.11 % 14.81 % autoconfig. mode #42 18.04 % 18.11 % ?1 ?1 0 hoc voc 1024 x 768 rgb in, ntsc out decrease horiz. (# of logical clicks) increase horiz. horizontally constant decrease vert. vertically const. increase vert. 0 +1 +1 100381_082 autoconfig. mode #11 13.44 % 14.24 % autoconfig. mode #43 16.20 % 16.67 % ?1 ?1 0 hoc voc 1024 x 768 rgb in, pal-bdghi out (# of logical clicks) (# of logical clicks) 0 +1 +1
CX25870/871 3.0 pc board considerations flicker-free video encoder with ultrascale technology 3.6 applications information 100381b conexant 3-25 customers are urged to enable the auto configuration mode that is in the middle of each chart as the default size fo r each active resolution. to accomplish this, the encoder?s config [5:0] bit field must be programmed to the desired mode. in addition, the graphics controller?s htotal register must be programmed to match the CX25870/871? s h_clki[10:0] value, and vtotal register must be programmed to matc h the CX25870/871?s v_linesi[10:0] value. other minor modifications may be necessary. the specific procedure to follow to enable different overscan ratios is explained in an application note titled supporting tv out with non-standard graphics input resolutions . request this document from your local conexant sales representative for help on the size video adjustment. a simpler alternative to independent horizontal and vertical size buttons is to replace the directional control pad with a slider. this slider would only have 3 tick marks and would cycle through the diff erent sizes available based on the autoconfiguration modes that exist for th e specific desktop resolution and video output type. this concept is illustrated in figure 3-13 . the slider would alter the horizontal and vertical size of the tv picture simultaneously by changing the overscan percentages by the same amount. size control should only be effective for desktop resolutions such as 640x480, 800x600, and 1024x768. nonstandard resolutions should choose a single size with a moderate amount of overscan co mpensation (hoc/voc = 11 percent?16 percent) and not allow the end-user to deviate from this choice by graying out the size slider. figure 3-13. direction-less size control pad
3.0 pc board considerations CX25870/871 3.6 applications information flicker-free video encoder with ultrascale technology 3-26 conexant 100381b 3.6.3 system block diagrams the CX25870/871 can be designed into any system that requires analog standard definition television outputs (ntsc/pa l/secam/scart) or high definition television outputs (yp b p r /hd rgb) based on a digital rgb or yc r cb set of inputs. the following system block diagrams ar e meant to illustrate several common applications which presently utilize the CX25870/871 encoder. figure 3-14. system block diagram for desktop/portable pc with tv out 100381_099 intel pentium iii? or amd k7? series cpu agp graphics controller cx25871 or bt869 north bridge core logic dimm*2 cpu clk memory bus ac '97 agp bus digital rgb or ycrcb pixels smbus parallel port serial port ide fdd i-f usb ports ata 33/066 gpio acpi core logic clk #1 lin in lin out mic in clks core logic clk #2 analog rgb control address data codec vga monitor ntsc/pal/secam television or hdtv clock generator ieee 1394 host controller pci/legacy audio controller pci cardbus pc controller pcmcia socket bios flash rom south bridge core logic pci riser device pci bus conexant vga encoder
CX25870/871 3.0 pc board considerations flicker-free video encoder with ultrascale technology 3.6 applications information 100381b conexant 3-27 3.6.4 electrostatic discharg e and latchup considerations correct electrostatic discharge (esd)-sensi tive handling procedures are required to prevent device damage. device damage can produce symptoms of catastrophic failure or erratic device behavior with leaky inputs. all logic inputs shou ld be held low until power to the device has settled to the specified tolerance. dac power decoupli ng networks with large time constants should be avoided; they could delay vaa and vdd power to the device. ferrite beads must be used only for analog power vaa decoupling. inductors cause a time-constant delay that induces latchup, and should not be substituted for a ferrite bead. latchup can be prevented by ensuring that all vaa and vdd pins are at the same potential and by forcing all agnd and vss pins to be at the same potential. the vaa and vdd supply voltage must be applied before the signal pin voltages. the correct power-up sequence ensures that any signal pin voltage will never exceed the power supply voltage. figure 3-15. system block diagram for graphics card with tv out 100381_100 agp graphics controller agp bus analog rgb analog rgb dac outputs clks sync*s and blank* digital rgb or ycrcb pixels cx25871 or bt869 vga monitor ntsc/pal/secam television or hdtv sgram*8 or sdram*8 voltage regulator graphics bios flash rom conexant vga encoder
3.0 pc board considerations CX25870/871 3.6 applications information flicker-free video encoder with ultrascale technology 3-28 conexant 100381b 3.6.5 clock and subcarrier stability the color subcarrier frequen cy is derived directly from the xtalin/xtalout ports when en_xclk=0. the color subcarrier frequency is derived directly from the main clock input, clki, when en_xcl k=1 (slave interface). in either case any jitter or frequency deviation from 13.500 mhz (xtalin/xtalout) or the clki (slave interface) rate will be tran sferred directly to the color subcarrier. jitter within the valid clock cycle interval will result in hue noise on the color subcarrier on the order of 0.9?1.6 degrees per nanosecond. random hue noise can result in degradation in the am/pm noise ratio (typically around 40 db for consumer media such as videodiscs and vcrs). periodic or coherent hue noise can result in differential phase error (which is limited to 10 degrees by fcc cable tv standards). any frequency deviation of clki from the transmitted clock (i.e., clko) will challenge the subcarrier tracking capability of the destination receiver. this may range from a few parts-per-million (ppm) for broadcast equipment, to 100 ppm for industrial equipment and to >100 ppm for consumer equipment. greater subcarrier tracking range generally results in poorer subcarrier decoding dynamic range. so, receivers that tolerate jitter and wide subcarrier frequency deviation will introduce more noise in the decoded image. crystal-based clock sources with a maximum total deviation of 50 ppm (ntsc) or 25 ppm (pal, secam) across the temperature range of 0 c to 70 c produce the best results for consumer and industrial applications. in rare cases, temperature-compensated clock sources with tighter toleran ces may be warranted for broadcast or more stringent pal (e.g., type i) applications. some applications call for maintainin g correct subcarrier-horizontal (sc-h) phasing for correct color framing. this requires subcarrier coherence within specified tolerances over a four-field inte rval for 525-line systems or 8 fields for 625-line systems. any clock interruption (even during vertical blanking interval) which results in mis-registration of the clki input or nonstandard pixel counts per line, can result in sc-h excursions outside the ntsc limit of 40 degrees (reference eia rs170a) or the pal li mit of 20 degrees (reference ebu d23-1984). in slave interface, any deviation ex ceeding the 50 ppm (ntsc) or 25 ppm (pal, secam) limits of the number clock cycles between hsync* falling edges may result in a switch to master mode. a list of recommended crystals and crystal vendors is contained in appendix b .
CX25870/871 3.0 pc board considerations flicker-free video encoder with ultrascale technology 3.6 applications information 100381b conexant 3-29 3.6.6 filtering radio freq uency modulator connection the CX25870/871 internal upsampling fi lter alleviates external filtering requirements by moving significant sampling alias components above 19 mhz and reducing the sinx/x aperture loss up to the filter?s passband cutoff of 5.75 mhz. while typical chrominance subcarrier decoders can handle the CX25870/871 output signals without analog filtering, the higher frequency alias products pose some emi concerns and may create troublesome images when introduced to a radio frequen cy (rf) modulator. when the video is presented to an rf modulator, it should be free of energy in the regi on of the aural subcarrier (4.5 mhz for ntsc, 5.5?6.5 mhz for pa l). hence some additional frequency traps may be necessary when the video si gnal contains fundamental or harmonic energy (as from unfiltered character generators) in that region. where better frequency response flatness is required, some peaking in the analog filter is appropriate to compensate fo r residual digital filter losses with sufficient margin to tolerate 10 percent reactive components. a three-pole elliptic filte r (one inductor, three cap acitors) with a 6.75 mhz passband can provide at least 45 db at tenuation (including sinx/x loss) of frequency components above 20 mhz and provide some flexibility for mild peaking or special traps. an inductor value with a self-resonant frequency above 80 mhz is chosen so that its intrinsic ca pacitance contributes less than 10 percent of the total effective circuit value. th e inductor itself may induce 1 percent (0.1 db) loss. any additional ferrites intr oduced for emi control should have less than 5 ? impedance below 5 mhz to minimize additional losses. the capacitor to ground at the CX25870/871 output pi n is compensating for the parasitic capacitance of the chip plus any protect ion diodes and lumped circuit traces (about 22 pf + 5 pf/diode). some filter peaking can be accomp lished by splitting the 75 ? source impedance across the reactive pi filter network. however, this will also introduce some chrominance-luminance delay distortion in the range of 10?20 ns for a maximum of 0.5 db boost at the subcarrier frequency. the filter network feeding an rf modu lator may include the aforementioned trap, which could take two forms depending on the depth of attenuation and type of resonator device employed. the trap circuitry can interact with the low-pass filter, compromising frequency response flatness. a simple pnp buffer can preserve the benefits of an oversampling encoder when simultaneous composite video baseband signals (cvbs) are required for driving external cables. in addition, an active video buffer, serves to isolate the rf modulato r signal amplitude from anomalies in the external termination. this buffer can be implemented with a transistor array or video amplify ic which provides a gain of two (before series termination), capable of driving 740 a into the 75 ? destination, and is biased within its input/output compliance range. when si multaneous y/c (s-video) outputs are not required, a second cvbs signal can be created (with a 600 mv sync to tip offset) by tying these pins together with a sing le termination resistor (typically 75 ? ) and driving the low-pass filter circuit. the rf modulator typically has a high input impedance (about 1 k ? 30 percent) and loose tolera nce. consequently, the amplitude variation at the modulator input will be greater, especially when the trap is properly terminated at the modulator input for ma ximum effect. some modulators, video or aural fidelity, degrade dramatically when over driven, so the value of the effective termination (nominally 37.5 ? ) may need to be adjusted downward to maintain sufficient linearity (or depth of mo dulation margin) in the rf signal.
3.0 pc board considerations CX25870/871 3.6 applications information flicker-free video encoder with ultrascale technology 3-30 conexant 100381b a two-section trap (with associated in ductor) may be warranted to achieve better than 20 db attenuation when st ereo, sap, or am aural carriers are generated, or when >40 db audio dyna mic range is desired. some impedance isolation (e.g., buffer) may be required before the trap to obtain the flattest frequency response.
CX25870/871 3.0 pc board considerations flicker-free video encoder with ultrascale technology 3.7 cx870evk evaluation kit 100381b conexant 3-31 3.7 cx870evk evaluation kit a new reference design kit is availabl e now to facilitate implementation of conexant?s vga encoder into a graphics subsystem. this kit is called the geforce2 mx-400 cx870evk and can be obtained through your local conexant systems sales office. the new CX25870 evaluation kit uses the nvidia p36 model reference design agp card, containing the popular nvidia geforce2 mx-400 ? graphics-processing unit (gpu), as a hi gh-performance data master to provide digital data to the CX25870 pc video encoder. the conexant device has been mounted directly on this graphics card along with all necessary passive components (resistors, capac itors, inductors, video conn ectors, etc.) to ensure proper device operation. this two-chip combination is controlled by a set of drivers for the graphics accelerator written by nvidia and a separate windows program called super cockpit created by conexant that allows direct manipulation of the encoder device by ci rcumventing the driver software. all the necessary documents and cables have been within the kit as well. the multipronged dv-h cable from jic usa is included with the kit and will be necessary for viewing of hdtv, 480i component video out, s-video, composite, and any other tv output from the CX25870 encoder. to obtain the necessary cx870evk softwa re, find a pc with internet access and visit the CX25870 https://site. for the site address, username, and password, contact your local conexant systems sales office. once you have been given user identification information, you can do wnload the geforce2 mx-400 cx870evk instruction manual, super cockpit, test images, and other pertinent software. the cx870evk was designed to be both a demonstration unit and development unit depending on a customer?s needs. for demonstration purposes, many script files have been created and will be automatically extracted and placed into a /scriptfiles subdirectory under the cx870evk?s main directory. to execute a script file, launch a dos-box, type the desired script filename (without the extension) on the command line, and then press the key. after execution, the script file will have configured both the CX25870 encoder and the geforce2 mx-400 gr aphics controller to a specific mode in terms of resolution and video output. this is th e most effective method for achieving the optimal tv out picture quickly. for development purposes, several new pages have been added to super cockput including the handy clipboard pages which allow the end-user to try out register values and restore them if the result is not desirable. all registers can be read from as well?an improvement over the bt868/9. write access to all the new bits and registers found within the cx25 870 are also possible. note that the geforce2 mx-400 controller supports the CX25870 in a pseudo-master interface. as a result, hdtv yp r p b output is possible with the geforce2 mx-400 cx870evk kit.
3.0 pc board considerations CX25870/871 3.7 cx870evk evaluation kit flicker-free video encoder with ultrascale technology 3-32 conexant 100381b in addition, the ability to switch between the most popular desktop resolutions (640x480, 800x600, and 1024x768) and video output types (ntsc/pal/secam) is much simpler no w than with the original bt868evk. finally, sliders commonly found on tv out display properties pages such as brightness, contrast, sa turation, flicker filtering and hue have been integrated into the super cockpit application itself on the display page. users are encouraged to manipulate these controls to achieve their desired tv outputs and save the encoder settings for future usage.
CX25870/871 3.0 pc board considerations flicker-free video encoder with ultrascale technology 3.8 serial interface 100381b conexant 3-33 3.8 serial interface 3.8.1 data transfer on the serial interface bus figure 3-16 illustrates the relationship betw een sid (serial interface data) and sic (serial interface clock) to be used when programming the internal registers via the serial interface bus. if the bus is not being used, both sid and sic lines must be left high. every byte put onto the si d line should be 8 bits lo ng (msb first), followed by an acknowledge bit, which is generated by the receiving device. each data transfer is initiated with a start condi tion and ended with a stop condition. the first byte after a start condition is always the slave device address byte. if this is the device?s own address, the device will generate an acknowledge by pulling the sid line low during the ninth clock pulse, then accept the data in subsequent bytes (auto-incrementing the subaddress) un til another stop condition is detected. the eighth bit of the addr ess byte is the read/write bit (high = read from addressed device; low = write to the ad dressed device). data bytes are always acknowledged during the ninth cloc k pulse by the addressed device. note: during the acknowledge period, the transmitting device must leave the sid line high. premature termination of the data transf er is allowed by generating a stop condition at any time. when this happen s, the CX25870/871 will remain in the state defined by the last complete data byte transmitted and any master acknowledge subsequent to reading the chip id (subaddress 0x89 if altaddr pin is 0) is ignored. the maximum serial interface spee d for the CX25870/871 is 400 khz.
3.0 pc board considerations CX25870/871 3.8 serial interface flicker-free video encoder with ultrascale technology 3-34 conexant 100381b figure 3-16. sid/sic serial programming diagram 1 sic 23456789 1 23456789 123456 789 subsequent bytes and acknowledge interpreted as data values for auto-incrementing subaddress locations sid msb lsb (1) (2) (2) start condition stop condition subaddress (xx) data (xx) (1) (1) slave main address (xx) 100381_021 note(s): (1) ack = acknowledge generated by CX25870/871. (2) conditions generated by master device.
100381b conexant 4-1 4 4.0 parametric information 4.1 dc electrical parameters dc electrical parameters are defined in tables 4-1 through 4-3 . ac electrical parameters are defined in table 4-4 . figures 4-1 through 4-10 provide timing diagrams. table 4-1. recommended operating condition parameter symbol min typical max units power supply vaa, vdd 3.15 3.30 3.45 v serial input supply (c x25870/871?s serial bus always operates at 3.3 v.) vdd_si 3.15 3.30 3.45 v low voltage supply (for interface to 1.8 v master) vddl, vdd_co 1.71 1.80 1.89 v low voltage supply (for interface to 1.5 v master) vddl, vdd_co 1.425 1.50 1.575 v low voltage supply (for interface to 1.3 v master) vddl, vdd_co 1.235 1.30 1.365 v low voltage supply (for interface to 1.1 v master) vddl, vdd_co 1.045 1.10 1.155 v voltage supply (for interface to 3.3 v master) vddl, vdd_co 3.15 3.30 3.45 v ambient operating temperature t a 0?70 c total dac terminated load r term ? 37.5 ? ? nominal rset r set 74.25 75.0 75.75 ?
4.0 parametric information CX25870/871 4.1 dc electrical parameters flicker-free video encoder with ultrascale technology 4-2 conexant 100381b table 4-2. absolute maximum rating parameter symbol min typ max units vaa, vdd (measured to gnd) ? ? ? 7.0 v vdd_si (measured to gnd) ? ? ? 7.0 v voltage on any signal pin (1) ? gnd ?0.5 vdd_si+ 0.5 v analog output short circuit duration to any power supply or common ground i sc ? ? unlimited sec storage temperature t s ?65 ? +150 c junction temperature t j ? ? +125 c vapor phase soldering (1 minute) t vsol ? ? 220 c thermal resistance of package ja ? 38.5 ? c/w note(s): 1. this device employs high-impedance cmos circuitry on all signal pi ns. it should be handled as an esd-sensitive device. voltage on any signal pin that exceeds the power supply or ground voltage by more th an 0.5 v can cause destructive latchup. 2. stresses above those liste d under ?absolute maximum ratings? can cause permanent damage to the device. this is a stress rating only, and functional operation of th e device at these or any other conditi ons above those liste d in the operational sections of this specification is not im plied. exposure to absolute maximum rating conditions for extended periods can affect device reliability.
CX25870/871 4.0 parametric information flicker-free video encoder with ultrascale technology 4.1 dc electrical parameters 100381b conexant 4-3 table 4-3. dc characteristics for CX25870/871 parameter symbol min typical max units video d/a resolution ? 10 10 10 bits output current-dac code 1023 (iout full scale) ? ? 34.13 ? ma output voltage-dac code 1023 ? ? 1.28 ? v video level error (nominal resistors) ? ? ? 5 % output capacitance (of dac output) ? ? 22 ? pf input high voltage @ 3.3 v (normal operation) vih 2.0 ? vdd + 0.5 v input high voltage @ 1.8 v (low voltage pins only) vih 1.0 ? vddl + 0.5 v input high voltage @ 1.1 v (low voltage pins only) vih 0.7 ? vddl + 0.5 v input low voltage @ 3.3 v (normal operation) vil gnd?0.5 ? 0.8 v input low voltage @ 1.8 v (low voltage pins only) vil gnd ? 0.5 ? 0.45 v input low voltage @ 1.1 v (low voltage pins only) vil gnd ? 0.5 ? 0.2 v input high current (vin = 2.4 v) iih ? ? 1 a input low current (vin = 0.4 v) iil ? ? ?1 a input capacitance (f =1 mh z, vin = 2.4 v) cin ? 7 ? pf input high voltage (sic, sid) vih 0.7 * vdd ? vdd + 0.5 v input low voltage (sic, sid) vil gnd ? 0.5 ? 0.3 * vdd v input high voltage (clki) vih 2.4 ? vdd_i + 0.5 v input low voltage (clki) vil gnd ? 0.5 ? 0.8 v output high voltage (ioh = ?400 a) voh 2.4 ? vdd v output low voltage (iol = 3.2 ma) vol gnd ? 0.4 v three-state current ioz ? ? 50 a output capacitance cdout ? 10 ? pf note(s): the above parameters are guarant eed over the full temperature range (0 c to 70 c), temperature coefficients are not specified or required. typical va lues are based on nominal temperature, i.e., r oom temperature, and nomin al voltage, i.e., 3.3 v.
4.0 parametric information CX25870/871 4.2 ac electrical parameters flicker-free video encoder with ultrascale technology 4-4 conexant 100381b 4.2 ac electrical parameters table 4-4. ac characteristics for CX25870/871 (1 of 3) parameter eia/tia 250c ref ccir 567 symbol min typical max units hue accuracy (2) ? ? ? 1.05 1.45 1.64 deg p?p chroma amplitude accuracy (2) ? ? ? 0.42 1.15 1.64 % p?p chroma am noise 1 mhz red field ? ? ?65.70 ?64.90 ?62.40 db rms chroma pm noise 1 mhz red field ? ? ?54.40 ?50.70 ?47.90 db rms differential gain 6.2.2. 1 c3.4.1.3 ? 0.26 0.5 0.7 % p?p differential phase 6.2.2.2 c3.4.1.4 ? 0.64 0.71 1.19 deg p?p rms snr (unweighted 100 ire y ramp tilt correct) 6.3.1 ? ? ?53.70 ?51.04 ?46.9 db rms peak periodic snr @ 3.58 mhz 6.3.2 ? ? ?82.7 ?79.2 ?73.4 db p?p 100 ire multiburst 6.1.1 ? ? 101.9 103.5 105.4 ire multiburst @ 0.50 mhz ? ? ? ?0.15 ?0.1 ?0.06 db multiburst @ 1.25 mhz ? ? ? ?0.27 ?0.21 ?0.16 db multiburst @ 2.00 mhz ? ? ? ?0.45 ?0.36 ?0.31 db multiburst @ 3.00 mhz ? ? ? ?0.73 ?0.61 ?0.54 db multiburst @ 3.58 mhz ? ? ? ?0.88 ?0.74 ?0.66 db multiburst @ 4.05 mhz ? ? ? ?1.03 ?0.89 ?0.81 db chroma/luma gain ineq 6.1. 2.2 c3.5.3.1 ? 94.8 96.2 97.1 % chroma/luma delay ineq 6.1. 2 c3.5.3.2 ? ?7.00 ?3.04 ?0.20 ns short time distortion 100 ire/pixel rising edge 6.1.6 ? ? 1.70 1.79 2.0 % luminance nonlinearity 6.2.1 ? ? 0.20 0.82 1.5 % p?p chroma/luma intermod 6.2.3 ? ? 0.00 0.28 0.5 % chroma nonlinear gain 6. 2.4.1 ? ? ?1.9 ?1.59 ?1.30 % chroma nonlinear phase 6 .2.4.2 ? ? 0.10 0.53 1.30 deg pixel/control setup time (setup_hold_adj bit = 0) ??13??ns pixel/control setup time (setup_hold_adj bit = 1) ??11.25??ns
CX25870/871 4.0 parametric information flicker-free video encoder with ultrascale technology 4.2 ac electrical parameters 100381b conexant 4-5 parameter eia/tia 250c ref ccir 567 symbol min typical max units pixel/control hold time (setup_hold_adj bit = 0) ??20??ns pixel/control hold time (setup_hold_adj bit = 1) ??21.5??ns control output delay time (4) ??3??10.0ns control output hold time (4) ??42? ns clki/o frequency (standard mode) ? ? ? ? ? 53.333 3 mhz clki/o pulse width low duty cycle (3) ???405060% clki/o pulse width high duty cycle (3) ???405060% clko to clki delay ? ? 7 ? ? 0.8 clko cycles slave to hsync*/vsync* three-state (3) ? ? 5 2 ? ? clki cycles slave to hsync*/vsync* active (3) ? ? 6 ? ? 2 clki cycles vaa supply current (minimum 3 dacs on) (8) ? ? ? ? 190 ? ma vdd supply current (minimum 3 dacs on) (8) ? ? ? ? 220 ? ma total supply current (minimum 3 dacs on) (8) ? ? ? ? 410 ? ma power-down current ? ? ? ? 3 (7) ?ma power-down current (need a hardware reset to bring the part up) ???? 1.5 (6) ?ma table 4-4. ac characteristics for CX25870/871 (2 of 3)
4.0 parametric information CX25870/871 4.2 ac electrical parameters flicker-free video encoder with ultrascale technology 4-6 conexant 100381b hdtv output timing characteristics: 1080i (see figure 4-9 ) parameter symbol min typical max units lowsync width ? 598.8 ? ns start of line to end of active video ? 28.385 ? s highsync width ? 598.8 ? ns rising edge of sync to start of broad pulse ? 1.796 ? s start of line to start of active video ? 2.588 ? s sync rise time ? 54.5 ? ns total line time ? ? 29.685 ? s active line time ? ? 25.778 ? s hdtv output timing characteristics: 720p (see figure 4-10 ) parameter symbol min typical max units lowsync width a ? 548 ? ns start of line to end of active video b ? 20.54 ? s high sync width c ? 548 ? ns rising edge of sync to start of broad pulse d ? 3.53 ? s rising edge of sync to st art of active video e ? 3.53 ? s sync rise time ? ? 54.7 ? ns total line time ? ? 22.2 ? s active line time ? ? 17.16 ? s note(s): 1. guaranteed by characterization; ntsc output , no vertical or horizontal sc aling. flicker filter and other internal low-pass fi lters bypassed, and contrast, brightness, saturation levels set to full scale. (2) 100/7.5/100/7.5 color bars normalized to burst. (3) guaranteed by design. (4) control pins are defined as: bl ank*, hsync*, vsync*, field, clko , clki, reset*, pal, and slave. (5) dac output load < 75 pf. hsync*, vsync*, blank*, and field output load < 75 pf. as the above parameters are guaranteed over the full temperat ure range, temperature coefficients are not spec ified or required. typi cal values are based on nominal temperature, i.e., room temperature, and nominal voltage, i.e., 3.3 v. (6) there are numerous power-down options. this value was dete rmined by setting sleep_en, dis_clki, dis_clko, by_pll, xtl_bfo_dis, xtal_pad_dis bits and pulling the sleep pin high. (7) this value was determined by se tting by_pll, sleep_ed, dis_clki, dis_clko, xtal_bfo_dis bits. (8) to ensure that the encoder performance fa lls within dc and ac electric al limits, no more than one dac should be disabled at any time. table 4-4. ac characteristics for CX25870/871 (3 of 3)
CX25870/871 4.0 parametric information flicker-free video encoder with ultrascale technology 4.2 ac electrical parameters 100381b conexant 4-7 figure 4-1. timing details for all interfaces clki p[23:0] hsync*,vsync* 1 2 3 4 .8 v 2.4 v blank* (output) hsync*,vsync*, blank* (input) 5 slave 1 2 1 2 hsync*,vsync* 6 (internal clki clock source) clko 7 100381_022
4.0 parametric information CX25870/871 4.2 ac electrical parameters flicker-free video encoder with ultrascale technology 4-8 conexant 100381b figure 4-2. master interface timing relationship/noninterlaced rgb/ycrcb input internal sample vsync* (output) clki hsync* (output) p[11:0] blank* (input) blank* (output) (mux mode) p[23:0] (non- clko internal line counter h_blanki - 3 mux mode) counter sample h_blank_1 sample h_blank_2 sample h_blank line 1 line v_blank1 +1 pol poh p1l p1h p2l pnh p0 p1 p2 pn p2h 100381_023
CX25870/871 4.0 parametric information flicker-free video encoder with ultrascale technology 4.2 ac electrical parameters 100381b conexant 4-9 figure 4-3. pseudo-master interface timing relationship ? active line/noninterlaced rgb input . . 100381_058 minimum 2 clks h_blanki[9:0] r7-0 g-lo r7-0 g-lo b7-0 g-up b7-0 g-up r7-0 g-lo b7-0 g-up r7-0 g-lo b7-0 g-up r7-0 g-lo b7-0 g-up r7-0 g-lo clki vsync* (input) blank* (optional input) [p11 - p0] hsync* (input) b7-0 g-up many clks 3 ns. minimum note(s): 1. the leading edge pixel data (r pixel + g4, g3, g2, and g0 in the 24-bit rgb multiplexed case) and trailing edge pixel data (b pixel + g7, g6, g5, and g1) is clocked in on the rising and falling edge of clki, respectively. 2. the CX25870's hsynci and vsynci bits (register 0 x c6) must be set to 0 (=default) in these timing diagrams. this configure s the CX25870 to check for active low signals on the hsync* and vsync* pins from the graphics controller. 3. the {r[7:0], g4, g3, g2, and g0} - {b[7:0], g7, g6, g5, and g1} sequence begins with rising edge of blank* or the h_blanki[ 9:0] pixel count. 4. the clock frequency (i.e., clki) transmitted by the graphics controller must not deviate 25 ppm from the clko frequency sen t by the CX25870/871. the CX25870 is the timing slave device to the graphics controller in pseudo-master interface. 5. 24-bit rgb multiplexed input format is illustrated in this diagram. it is assumed CX25870's in_mode[3:0] bits = 0000.
4.0 parametric information CX25870/871 4.2 ac electrical parameters flicker-free video encoder with ultrascale technology 4-10 conexant 100381b figure 4-4. pseudo-master timing relationship blank line/noninterlaced rgb/ycrcb input 100381_059 minimum 2 clks minimum 2 clks v_blanki[7:0] many lines many lines 3 ns. minimum start of active video clki hsync* (input) vsync* (input) blank* (optional input) [p11 - p0] note(s): 1. for noninterlaced data transmission, to start each frame, the leading edge of hsync* and the leading edge of vsync* must b e coincident (within 1 clki clock cycle). the location of these signals' respective trailing edges is not important relativ e to each other. 2. the duration of the hsync* pulse must be at least 2 complete clki cycles. the duration of the vsync* pulse must be a minimum of 2 clki cycles as well. it is acceptable for the hsync* to remain low for longer than 2 clki cycles but the signal's ri sing edge must be received by the CX25870 at least 1 pixel before the next hsync* falling edge which denotes the start of the next line. likewise, vsync* can stay low for much longer than 2 clki cycles but the signal's rising edge must be received by the cx870 at leas t 1 complete line before the next vsync* falling edge which denotes the start of the next frame. 3. if a blank* signal is not used as part of the physical interface to a graphics controller, then the CX25870's h_blank[9:0] and v_blanki[7:0] registers must be programmed with values equivalent to the correct amount of horizontal pixel blanking and vertical line blanking from the master.
CX25870/871 4.0 parametric information flicker-free video encoder with ultrascale technology 4.2 ac electrical parameters 100381b conexant 4-11 figure 4-5. slave interface timing relationship/noninterlaced rgb/ycrcb input clko clki vsync* (input) hsync* (input) blank* (input) blank* (output) internal sample h_blanki pol poh p1l p1h p2l pnl pnh p0 p1 p2 pn sample1 sample hclki sample h_blanki -2 sample h_blanki sample h_blanki -1 counter 100381_024
4.0 parametric information CX25870/871 4.2 ac electrical parameters flicker-free video encoder with ultrascale technology 4-12 conexant 100381b figure 4-6. slave interface timing relationship/interlaced nonmultiplexed rgb input (fld_mode = 10 ? default) 100381_074 rgb0 clko clki odd field many hsync*'s even field blank* (input) hsync* (input) ysync* (input) hsync* (input) ysync* (input) rgb1 rgb2 rgb3 rgb4 rgb5 rgb6 rgb7 at least 4 clkis at least 4 clkis note(s): 1. the CX25870's div2 bit must be set. 2. fld_mode[1:0] defined in table 2-5.
CX25870/871 4.0 parametric information flicker-free video encoder with ultrascale technology 4.2 ac electrical parameters 100381b conexant 4-13 figure 4-7. slave interface timing relationship/interlaced nonmultiplexed ycrcb input (fld_mode = 01) 100381_075 cb0 clko clki odd field many hsync*'s even field blank* (input) hsync* (input) ysync* (input) hsync* (input) ysync* (input) y0 cr0 y1 cb2 y2 cr2 y3 at least 4 clkis at least 4 clkis note(s): 1. the CX25870's div2 bit must be set. 2. fld_mode[1:0] defined in table 2-5.
4.0 parametric information CX25870/871 4.2 ac electrical parameters flicker-free video encoder with ultrascale technology 4-14 conexant 100381b figure 4-8. slave interface timing relationship/interlaced nonmultiplexed ycrcb input (fld_mode = 00) 100381_076 cb0 1/4 of a line 1/4 of a line 1/4 of a line 1/4 of a line 1/4 of a line clko clki odd field many hsync*'s even field blank* (input) hsync* (input) ysync* (input) hsync* (input) ysync* (input) y0 cr0 y1 cb2 y2 cr2 y3 note(s): 1. the CX25870's div2 bit must be set. 2. fld_mode[1:0] defined in table 2-5.
CX25870/871 4.0 parametric information flicker-free video encoder with ultrascale technology 4.2 ac electrical parameters 100381b conexant 4-15 figure 4-9. hdtv output horizontal timing details: 1080i 100381_089 +300 +300 +300 +700 +350 ?300 ?300 ?300 ?350 0 blanking vertical sync (interfaced) p b ,p r (outputs) y,r,g,b (outputs) broad pulse 0 h 0 h 0 h 0 0 z note(s): 1. values for , , , , , and are given in table 4-4. 2. sync rise time ( ) is not shown here. 3. amplitudes are expressed in mv.
4.0 parametric information CX25870/871 4.2 ac electrical parameters flicker-free video encoder with ultrascale technology 4-16 conexant 100381b figure 4-10. hdtv output horizontal timing details: 720p 100381_090 +300 mv +300 mv +300 mv +700 mv +350 mv ?300 mv d b b ?300 mv ?300 mv ?350 mv 0 mv blanking vertical sync (interfaced) p b ,p r (outputs) y,r,g,b (outputs) broad pulse 0 h 0 h 0 mv 0 mv e c a note(s): 1. values for a, b, c, d, and e are given in table 4-4. 2. sync rise time is not shown here. 3. amplitudes are expressed in mv.
CX25870/871 4.0 parametric information flicker-free video encoder with ultrascale technology 4.3 mechanical drawing for 80-pin pqfp 100381b conexant 4-17 4.3 mechanical draw ing for 80-pin pqfp a detailed mechanical diagram for the CX25870 and the cx25871 intergrated circuit is illustrated in figure 4-11 . figure 4-11. 80-pin pqfp package diagram d e a a2 ref. a1 1.60 (.063) l d1 80 pqfp - 1.6/0.15 mm form e2 e1 e b d2 s y m b o l all dimensions in millimeters min. nom. max. ---- 0.05 16.95 16.95 0.73 0.25 ---- ---- 2.0 ref. ---- 14.0 ref. 12.35 ref. ---- 14.0 ref. 12.35 ref. 0.80 1.6 ref. 0.65 bsc. ---- 2.4 0.35 17.45 17.45 1.03 0.45 a a 1 a 2 d d 1 d 2 e e 1 e 2 l l 1 e b top view bottom view side view detail a 100381_025
4.0 parametric information CX25870/871 4.3 mechanical drawing for 80-pin pqfp flicker-free video encoder with ultrascale technology 4-18 conexant 100381b
100381b conexant a-1 a49 appendix a scaling and i/0 timing register calculations the calculated values are used to progra m the registers controlling the total active pixels and lines in the input frame and the output field, as well as the vertical scaling register and the clock pll regist ers. these calculations assume pixel resolution for synchronizing the graphics controller, master interface operation unless otherwise stated, and requ ire the following input values: mfp?minimum front porch blanking in the input in clocks = max (12, controller_minimum_fro nt_porch_blanking_clocks); mbp?minimum back porch blanking in the input in clocks = max (4, controller_minimum_back_porch_blanking_clocks); voc?desired vertical overscan compensation (e.g., 0.15) hoc?desired horizontal overscan compensation (e.g., 0.15) v_activei?active lines per input frame (e.g., 480 or 600 or 768) h_active?active pixels per input line (e.g., 640 or 800 or 1024) alo?target active lines per output field (see table a-3 ) tlo?total lines per output field (see table a-3 ) ato?active time per output line (see table a-3 ) tto?total time per output line (see table a-3 ) tables a-1 and a-2 contain details of the supp orted video output formats. table a-3 details the constant software valu es depending on the video output. figures a-1 through a-8 illustrate allowable overscan compensation pairs for the most common desktop active resolutions. tables a-3 through a-27 list the most common overscan values for the 640 x 480, 800 x 600, and 1024 x 768 active resolutions that enable dual display on both the vga monitor and tv.
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-2 conexant 100381b table a-1. target video parameters for standard definition tv output formats (1 of 2) parameter description ntsc-m ntsc-j pal-m pal-60 pal- b,d,g,h,i pal-n pal-nc secam hsync width ( s) 4.7 4.7 4.7 4.7 4.7 4.7 4.7 4.7 hsync and vsync height (v) 0.286 0.286 0.287 0.3 0.3 0.2857 0.3 0.3 hsync rise/fall time (10% to 90%) (ns) 150 150 150 150 200 (1) 200 200 200 burst or subcarrier start ( s) 5.3 5.3 5.8 5.3 5.6 5.6 5.6 5.6 burst width ( s) 2.514 (9 cycles) 2.514 (9 cycles) 2.52 (9cycles) 2.25 (10 cycles) 2.25 (10 cycles) 2.25 (10 cycles) 2.51 (9 cycles) n/a subcarrier frequency (5) (hz) 3579545 3579545 3579611.49 4433618.75 4433618.75 4433618.75 3582056.25 for=4406250 fob=4250000 burst or subcarrier height (v) 0.2857 0.2857 0.306 0.3 0.3 0.3 0.3 0.161 phase alternation no no yes yes yes yes yes no number of lines per frame 525 525 525 525 625 625 625 625 line frequency (hz) 15734.264 15734.264 15734.264 15734.264 15625 15625 15625 15625 field frequency (hz) 59.94 59.94 59.94 59.94 50 50 50 50 setup yes no yes no no yes no no first active line 22 (3) 22 (3) 22 (3) 22 (3) 23 (4) 23 (4) 23 (4) 23 (4) last active line 262 (3) 262 (3) 262 (3) 262 (3) 309 (4) 309 (4) 309 (4) 309 (4) hsync to blank end ( s) 9.2[9.037] 9.2 9.2 9.2 10.5[9.778] 9.2 10.5 10.5 blank begin to hsync ( s) 1.5[1.185] 1.5 1.5 1.5 1.5[0.889] 1.5 1.5 1.5 black to 100% white (v) 0.661 0.714 0.661 0.7 0.7 0.661 0.7 0.7
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-3 number of lines each for vertical serration, equalization 3 3 3 3 2.5 3 2.5 2.5 note(s): (1) value for pal-i is 250 ns. 2. itu-r bt.601 blanking values given in square brackets []. (3) using ntsc line numbering convention from itu-r bt.470. (4) using pal line numbering convention from itu-r bt.470. (5) when programming the subcarrier in crement, use relationship of f sc to f h as given in itu-r bt.470 instead of f sc to f clk. table a-1. target video parameters for standard definition tv output formats (2 of 2) parameter description ntsc-m ntsc-j pal-m pal-60 pal- b,d,g,h,i pal-n pal-nc secam table a-2. key parameters for supported standard definition video output formats mode ntsc ntsc- 60hz pal- bdghi pal-n pal-nc pal-m pal-60 fsc (hz) 3,579,545 3,579,545 4,433,618.75 4, 433,618.75 3,582,056.25 3, 575,611.88 4,433,619.49 burst start 5.3 s5.3 s 5.60 s 5.60 s 5.60 s 5.80 s 5.60 s burst end 7.82 s 7.82 s 7.85 s 7.85 s 8.11 s 8.32 s 7.85 s hsync width (1) 4.70 s 4.70 s 4.70 s 4.70 s 4.70 s 4.70 s 4.70 s hsync frequency (1) 63.555 s64 s 64 s 64 s64 s 63.555 s 64 s active begin 9.40 s 9.40 s 10.5 s 9.40 s 10.5 s 9.40 s 10.5 s image center 35.667 s 35.667 s 36.407 s 35.667 s 36.407 s 35.667 s 36.407 s blank begin to hsync (1) 1.50 s 1.50 s 1.50 s 1.50 s 1.50 s 1.50 s 1.50 s note(s): (1) hsync in this table refers to the analog horizontal synchronization pulse that starts every scan line. table a-3. constant values dependent on encoding mode modes interlaced noninterlaced pal ntsc pal ntsc alo 288 243 288 243 tlo 312.5 262.5 312 262 ato 52.0 s 52.65556 s 52.0 s 52.65556 s tto 64.0 s 63.55556 s 64.0 s 63.55556 s
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-4 conexant 100381b figure a-1. allowable overscan compensation ratios for dual display, 640x480 input, ntsc output with 20 clock hblank period 8 10 12 14 16 18 20 22 8 10 12 14 16 18 20 22 vertical overscan compensation percentage horizontal overscan compensation percentage overscan compensation pecentage pairs for 640x480 ntsc 100381_026 = pixel clock solution = 8-cycle character clock solution = 9-cycle character clock solution legend: note(s): use this chart for pal-m and pal-60 allowable overscan ratios.
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-5 figure a-2. allowable overscan compensation ratios for d ual display, 640x480 input, pal-bdghi output with 20 clock hblank period 8 10 12 14 16 18 20 22 8 10 12 14 16 18 20 22 24 vertical overscan compensation percentage horizontal overscan compensation percentage overscan compensation pecentage pairs for 640x480 pal 100381_027 = pixel clock solution = 8-cycle character clock solution = 9-cycle character clock solution legend: note(s): use this chart for secam, pal-n, and pal-nc allowable overscan compensation ratios.
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-6 conexant 100381b figure a-3. allowable overscan compensation ratios for dual display, 800x600 input, ntsc output note(s): use this chart for pal-m and pal-60 allowable overscan ratios. 8 10 12 14 16 18 20 22 8 10 12 14 16 18 20 22 24 vertical overscan compensation percentage horizontal overscan compensation percentage overscan compensation percentage pairs for 800x600 ntsc 0 s horizontal blanking 1 s 2 s 3 s .75 s 100381_028 = pixel clock solution = 8-cycle character clock solution = 9-cycle character clock solution legend:
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-7 figure a-4. allowable overscan compensation ratios for dual display, 800x600 input, pal?bdghi output, standard clocking mode
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-8 conexant 100381b figure a-5. allowable overscan compensation ratios for dual display, 800x600 input, ntsc output in 3:2 clocking mode 8 10 12 14 16 18 20 22 8 10 12 14 16 18 20 22 vertical overscan compensation percentage horizontal overscan compensation percentage legend = pixel clock solution = 8-cycle character clock solution = 9-cycle character clock solution note(s): 1. all overscan solutions on this chart can be enabled by a data master that requires no more than 4 s of mblank time per line. 2. use this chart for pal-m and pal-60 allowable overscan ratios.
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-9 figure a-6. allowable overscan compensation ratios for dual display, 800x600 input, pal-bdghi output in 3:2 clocking mode 8 10 12 14 16 18 20 22 8 10 12 14 16 18 20 22 vertical overscan compensation percentage horizontal overscan compensation percentage legend = pixel clock solution = 8-cycle character clock solution = 9-cycle character clock solution 100381_066 note(s): 1. all overscan solutions on this chart can be enabled by a data master that requires no more than 8 s of hblank time per line. 2. use this chart for secam, pal-n, and pal-nc allowable overscan compensation ratios.
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-10 conexant 100381b figure a-7. allowable overscan compensation ratios for dual display, 1024x768 input, ntsc output note(s): use this chart for pal-m and pal-60 allowable overscan ratios. 8 10 12 14 16 18 20 22 8 10 12 14 16 18 20 22 0 us 1 us horizontal blanking 1.5 us 1.75 us 2 us 3 us 4 us horizontal overscan compensation percentage vertical overscan compensation percentage 100381_063 legend = pixel clock solution = 8-cycle character clock solution = 9-cycle character clock solution
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-11 figure a-8. allowable overscan compensation ratios for dual display, 1024x768 input, pal-bdghi output 8 10 12 14 16 18 20 22 8 10 12 14 16 18 20 22 24 vertical overscan compensation percentage horizontal overscan compensation percentage legend = pixel clock solution = 8-cycle character clock solution = 9-cycle character clock solution 100381_065 note(s): 1. all overscan solutions on this chart can be enabled by a data master that requires no more than 3 s of hblank time per line. 2. use this chart for secam, pal-n, and pal-nc allowable overscan compensation ratios.
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-12 conexant 100381b table a-4. overscan values, 640 x 480 ntsc, pixel-based cont roller, 1-pixel resolution, 2.5 s hblank (1 of 2) controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical resolution 780 665 190 988 21.81 21.81 0.00 780 595 212 884 12.61 12.76 ?0.14 784 600 210 896 13.79 13.58 0.21 780 630 200 936 17.47 17.70 ?0.23 777 575 220 851 9.23 9.47 ?0.24 785 630 200 942 18.00 17.70 0.30 777 625 202 925 16.49 16.87 ?0.38 777 650 194 962 19.70 20.16 ?0.46 775 588 215 868 11.00 11.52 ?0.52 775 651 194 961 19.62 20.16 ?0.55 777 600 210 888 13.01 13.58 ?0.57 775 609 207 899 14.07 14.81 ?0.74 775 630 200 930 16.94 17.70 ?0.76 790 630 200 948 18.51 17.70 0.82 791 600 210 904 14.55 13.58 0.97 770 645 196 946 18.34 19.34 ?1.00 770 585 216 858 9.97 11.11 ?1.14 770 660 191 968 20.20 21.40 ?1.20 770 615 205 902 14.36 15.64 ?1.28 770 630 200 924 16.40 17.70 ?1.30 795 630 200 954 19.03 17.70 1.33 770 600 210 880 12.22 13.58 ?1.36 795 595 212 901 14.26 12.76 1.51 765 665 190 969 20.28 21.81 ?1.53 798 650 194 988 21.81 20.16 1.65 798 600 210 912 15.30 13.58 1.72 798 625 202 950 18.69 16.87 1.81 800 630 200 960 19.53 17.70 1.84 765 630 200 918 15.85 17.70 ?1.84 765 595 212 867 10.90 12.76 ?1.86 800 609 207 928 16.76 14.81 1.94
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-13 798 575 220 874 11.62 9.47 2.15 763 600 210 872 11.41 13.58 ?2.17 800 588 215 896 13.79 11.52 2.26 805 630 200 966 20.03 17.70 2.34 760 630 200 912 15.30 17.70 ?2.40 805 615 205 943 18.08 15.64 2.44 805 600 210 920 16.03 13.58 2.45 805 645 196 989 21.89 19.34 2.55 756 650 194 936 17.47 20.16 ?2.69 756 625 202 900 14.17 16.87 ?2.70 805 585 216 897 13.88 11.11 2.77 810 630 200 972 20.53 17.70 2.83 755 630 200 906 14.74 17.70 ?2.96 805 570 222 874 11.62 8.64 2.97 756 600 210 864 10.59 13.58 ?2.99 table a-4. overscan values, 640 x 480 ntsc, pixel-based cont roller, 1-pixel resolution, 2.5 s hblank (2 of 2) controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical resolution
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-14 conexant 100381b table a-5. overscan values, 640 x 480 ntsc, character clo ck-based controller, 8-pixel resolution, 2.5 s hblank controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical resolution 784 600 210 896 13.79 13.58 0.21 800 630 200 960 19.53 17.70 1.84 800 609 207 928 16.76 14.81 1.94 800 588 215 896 13.79 11.52 2.26 760 630 200 912 15.30 17.70 ?2.40 840 615 205 984 21.50 15.64 5.86 840 600 210 960 19.53 13.58 5.95 840 610 207 976 20.85 14.81 6.04 840 595 212 952 18.86 12.76 6.10 840 605 209 968 20.20 13.99 6.21 840 590 214 944 18.17 11.93 6.23 840 585 216 936 17.47 11.11 6.36 840 580 218 928 16.76 10.29 6.47 720 665 190 912 15.30 21.81 ?6.51 840 575 220 920 16.03 9.47 6.57 840 570 222 912 15.30 8.64 6.66 720 630 200 864 10.59 17.70 ?7.10
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-15 table a-6. overscan values, 640 x 480 ntsc, character clo ck-based controller, 9-pixel resolution, 2.5 s hblank controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical resolution 765 665 190 969 20.28 21.81 ?1.53 765 630 200 918 15.85 17.70 ?1.84 765 595 212 867 10.90 12.76 ?1.86 756 650 194 936 17.47 20.16 ?2.69 756 625 202 900 14.17 16.87 ?2.70 810 630 200 972 20.53 17.70 2.83 756 600 210 864 10.59 13.58 ?2.99 810 595 212 918 15.85 12.76 3.09 819 600 210 936 17.47 13.58 3.89 819 625 202 975 20.77 16.87 3.90 819 575 220 897 13.88 9.47 4.42 720 665 190 912 15.30 21.81 ?6.51 720 630 200 864 10.59 17.70 ?7.10 855 595 212 969 20.28 12.76 7.52 693 650 194 858 9.97 20.16 ?10.20 882 575 220 966 20.03 9.47 10.57 900 574 220 984 21.50 9.47 12.03 675 665 190 855 9.65 21.81 ?12.16
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-16 conexant 100381b table a-7. overscan values, 640 x 480 pal-bdghi, pixel-based controller, 1-pixel resolution, 2.5 s hblank (1 of 3) controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical resolution 945 625 240 945 16.65 16.67 ?0.02 946 625 240 946 16.73 16.67 0.07 944 625 240 944 16.56 16.67 ?0.11 947 625 240 947 16.82 16.67 0.16 943 625 240 943 16.47 16.67 ?0.20 948 625 240 948 16.91 16.67 0.24 942 625 240 942 16.38 16.67 ?0.29 949 625 240 949 17.00 16.67 0.33 941 625 240 941 16.29 16.67 ?0.37 950 625 240 950 17.09 16.67 0.42 950 600 250 912 13.63 13.19 0.44 940 625 240 940 16.20 16.67 ?0.46 950 650 231 988 20.27 19.79 0.48 950 575 261 874 9.88 9.38 0.50 951 625 240 951 17.17 16.67 0.51 939 625 240 939 16.11 16.67 ?0.55 952 625 240 952 17.26 16.67 0.59 938 625 240 938 16.02 16.67 ?0.64 953 625 240 953 17.35 16.67 0.68 937 625 240 937 15.93 16.67 ?0.73 954 625 240 954 17.43 16.67 0.77 936 625 240 936 15.84 16.67 ?0.82 955 625 240 955 17.52 16.67 0.85 935 625 240 935 15.75 16.67 ?0.91 956 625 240 956 17.61 16.67 0.94 934 625 240 934 15.66 16.67 ?1.00 957 625 240 957 17.69 16.67 1.02 933 625 240 933 15.57 16.67 ?1.09 958 625 240 958 17.78 16.67 1.11 932 625 240 932 15.48 16.67 ?1.18 959 625 240 959 17.86 16.67 1.20
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-17 931 625 240 931 15.39 16.67 ?1.27 960 625 240 960 17.95 16.67 1.28 930 625 240 930 15.30 16.67 ?1.36 961 625 240 961 18.03 16.67 1.37 962 625 240 962 18.12 16.67 1.45 929 625 240 929 15.21 16.67 ?1.46 963 625 240 963 18.20 16.67 1.54 928 625 240 928 15.12 16.67 ?1.55 964 625 240 964 18.29 16.67 1.62 927 625 240 927 15.03 16.67 ?1.64 925 650 231 962 18.12 19.79 ?1.67 965 625 240 965 18.37 16.67 1.71 926 625 240 926 14.94 16.67 ?1.73 966 625 240 966 18.46 16.67 1.79 925 625 240 925 14.84 16.67 ?1.82 967 625 240 967 18.54 16.67 1.88 925 600 250 888 11.30 13.19 ?1.90 924 625 240 924 14.75 16.67 ?1.91 968 625 240 968 18.63 16.67 1.96 923 625 240 923 14.66 16.67 ?2.01 969 625 240 969 18.71 16.67 2.04 922 625 240 922 14.57 16.67 ?2.10 970 625 240 970 18.79 16.67 2.13 921 625 240 921 14.47 16.67 ?2.19 971 625 240 971 18.88 16.67 2.21 920 625 240 920 14.38 16.67 ?2.29 972 625 240 972 18.96 16.67 2.30 973 625 240 973 19.04 16.67 2.38 919 625 240 919 14.29 16.67 ?2.38 974 625 240 974 19.13 16.67 2.46 918 625 240 918 14.19 16.67 ?2.47 table a-7. overscan values, 640 x 480 pal-bdghi, pixel-based controller, 1-pixel resolution, 2.5 s hblank (2 of 3) controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical resolution
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-18 conexant 100381b 975 625 240 975 19.21 16.67 2.54 917 625 240 917 14.10 16.67 ?2.57 976 625 240 976 19.29 16.67 2.63 975 600 250 936 15.84 13.19 2.65 916 625 240 916 14.01 16.67 ?2.66 977 625 240 977 19.38 16.67 2.71 915 625 240 915 13.91 16.67 ?2.75 978 625 240 978 19.46 16.67 2.79 975 575 261 897 12.19 9.38 2.81 914 625 240 914 13.82 16.67 ?2.85 979 625 240 979 19.54 16.67 2.87 913 625 240 913 13.72 16.67 ?2.94 980 625 240 980 19.62 16.67 2.96 table a-7. overscan values, 640 x 480 pal-bdghi, pixel-based controller, 1-pixel resolution, 2.5 s hblank (3 of 3) controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical resolution
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-19 table a-8. overscan values, 640 x 480 pal-bdghi, character clock-based controller, 8-pixel resolution, 2.5 s hblank controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical resolution 944 625 240 944 16.56 16.67 ?0.11 952 625 240 952 17.26 16.67 0.59 936 625 240 936 15.84 16.67 ?0.82 960 625 240 960 17.95 16.67 1.28 928 625 240 928 15.12 16.67 ?1.55 968 625 240 968 18.63 16.67 1.96 920 625 240 920 14.38 16.67 ?2.29 976 625 240 976 19.29 16.67 2.63 912 625 240 912 13.63 16.67 ?3.04 984 625 240 984 19.95 16.67 3.28 904 625 240 904 12.87 16.67 ?3.80 992 625 240 992 20.60 16.67 3.93 1000 625 240 1000 21.23 16.67 4.56 896 625 240 896 12.09 16.67 ?4.58 1000 620 242 992 20.60 15.97 4.62 1000 615 244 984 19.95 15.28 4.67 1000 610 246 976 19.29 14.58 4.71 1000 605 248 968 18.63 13.89 4.74 1000 600 250 960 17.95 13.19 4.75 1000 630 239 1008 21.86 17.01 4.84 1000 575 261 920 14.38 9.38 5.01 1000 580 259 928 15.12 10.07 5.05 1000 585 257 936 15.84 10.76 5.08 1000 590 255 944 16.56 11.46 5.10 1000 595 253 952 17.26 12.15 5.11 1008 625 240 1008 21.86 16.67 5.19 888 625 240 888 11.30 16.67 ?5.37 880 625 240 880 10.49 16.67 ?6.18 872 625 240 872 9.67 16.67 ?7.00
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-20 conexant 100381b table a-9. overscan values, 640 x 480 pal-bdghi, character clock-based controller, 9-pixel resolution, 2.5 s hblank controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical resolution 945 625 240 945 16.65 16.67 ?0.02 954 625 240 954 17.43 16.67 0.77 936 625 240 936 15.84 16.67 ?0.82 963 625 240 963 18.20 16.67 1.54 927 625 240 927 15.03 16.67 ?1.64 972 625 240 972 18.96 16.67 2.30 918 625 240 918 14.19 16.67 ?2.47 981 625 240 981 19.71 16.67 3.04 909 625 240 909 13.35 16.67 ?3.32 990 625 240 990 20.44 16.67 3.77 900 650 231 936 15.84 19.79 ?3.95 900 625 240 900 12.48 16.67 ?4.19 999 625 240 999 21.15 16.67 4.49 891 625 240 891 11.59 16.67 ?5.07 1008 625 240 1008 21.86 16.67 5.19 882 625 240 882 10.69 16.67 ?5.97 873 625 240 873 9.77 16.67 ?6.89
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-21 table a-10. overscan values, 800 x 600 ntsc, pixel-based controller, 1-pixel resolution (1 of 4) controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical resolution 800 777 203 1184 18.45 16.46 1.98 800 819 193 1248 22.63 20.58 2.05 800 798 198 1216 20.59 18.52 2.07 800 756 209 1152 16.18 13.99 2.19 800 714 221 1088 11.25 9.05 2.20 800 735 215 1120 13.79 11.52 2.26 805 825 191 1265 23.67 21.40 2.27 805 780 202 1196 19.26 16.87 2.39 805 750 210 1150 16.03 13.58 2.45 805 765 206 1173 17.68 15.23 2.45 805 810 195 1242 22.25 19.75 2.50 805 720 219 1104 12.54 9.88 2.66 805 795 199 1219 20.79 18.11 2.68 805 735 215 1127 14.32 11.52 2.80 810 805 196 1242 22.25 19.34 2.91 810 770 205 1188 18.72 15.64 3.08 812 750 210 1160 16.76 13.58 3.18 810 735 215 1134 14.85 11.52 3.33 819 800 197 1248 22.63 18.93 3.70 815 735 215 1141 15.37 11.52 3.85 819 750 210 1170 17.47 13.58 3.89 819 775 204 1209 20.13 16.05 4.08 825 805 196 1265 23.67 19.34 4.33 819 725 218 1131 14.62 10.29 4.34 825 784 201 1232 21.62 17.28 4.34 820 735 215 1148 15.89 11.52 4.37 825 777 203 1221 20.92 16.46 4.46 825 798 198 1254 23.00 18.52 4.48 825 770 205 1210 20.20 15.64 4.56 826 750 210 1180 18.17 13.58 4.59 825 791 200 1243 22.32 17.70 4.62
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-22 conexant 100381b 825 763 207 1199 19.47 14.81 4.65 825 756 209 1188 18.72 13.99 4.73 825 749 211 1177 17.96 13.17 4.79 825 742 213 1166 17.19 12.35 4.84 825 735 215 1155 16.40 11.52 4.88 825 714 221 1122 13.94 9.05 4.89 825 728 217 1144 15.59 10.70 4.89 825 721 219 1133 14.77 9.88 4.90 833 750 210 1190 18.86 13.58 5.28 830 735 215 1162 16.90 11.52 5.38 840 780 202 1248 22.63 16.87 5.76 840 785 201 1256 23.12 17.28 5.84 835 735 215 1169 17.40 11.52 5.88 840 765 206 1224 21.11 15.23 5.88 840 790 200 1264 23.61 17.70 5.91 840 750 210 1200 19.53 13.58 5.95 840 770 205 1232 21.62 15.64 5.99 840 755 209 1208 20.07 13.99 6.07 840 775 204 1240 22.13 16.05 6.08 840 740 213 1184 18.45 12.35 6.10 840 760 208 1216 20.59 14.40 6.19 840 730 216 1168 17.33 11.11 6.22 840 745 212 1192 18.99 12.76 6.24 840 720 219 1152 16.18 9.88 6.30 840 735 215 1176 17.89 11.52 6.37 840 725 218 1160 16.76 10.29 6.47 840 715 221 1144 15.59 9.05 6.54 847 750 210 1210 20.20 13.58 6.62 850 777 203 1258 23.24 16.46 6.78 845 735 215 1183 18.38 11.52 6.85 850 756 209 1224 21.11 13.99 7.12 table a-10. overscan values, 800 x 600 ntsc, pixel-based controller, 1-pixel resolution (2 of 4) controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical resolution
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-23 854 750 210 1220 20.85 13.58 7.27 850 735 215 1190 18.86 11.52 7.33 855 770 205 1254 23.00 15.64 7.36 850 714 221 1156 16.47 9.05 7.42 855 735 215 1197 19.33 11.52 7.81 861 750 210 1230 21.50 13.58 7.92 861 775 204 1271 24.03 16.05 7.98 860 735 215 1204 19.80 11.52 8.28 861 725 218 1189 18.79 10.29 8.50 868 750 210 1240 22.13 13.58 8.55 865 735 215 1211 20.26 11.52 8.74 875 762 207 1270 23.97 14.81 9.15 875 750 210 1250 22.75 13.58 9.17 870 735 215 1218 20.72 11.52 9.20 875 759 208 1265 23.67 14.40 9.26 875 747 211 1245 22.44 13.17 9.27 875 744 212 1240 22.13 12.76 9.37 875 756 209 1260 23.36 13.99 9.37 875 741 213 1235 21.81 12.35 9.47 875 753 210 1255 23.06 13.58 9.48 875 726 217 1210 20.20 10.70 9.50 875 738 214 1230 21.50 11.93 9.56 875 723 218 1205 19.87 10.29 9.58 875 735 215 1225 21.18 11.52 9.65 875 720 219 1200 19.53 9.88 9.66 875 717 220 1195 19.20 9.47 9.73 875 732 216 1220 20.85 11.11 9.74 882 750 210 1260 23.36 13.58 9.78 875 714 221 1190 18.86 9.05 9.80 875 729 217 1215 20.53 10.70 9.83 880 735 215 1232 21.62 11.52 10.10 table a-10. overscan values, 800 x 600 ntsc, pixel-based controller, 1-pixel resolution (3 of 4) controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical resolution
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-24 conexant 100381b 889 750 210 1270 23.97 13.58 10.39 882 725 218 1218 20.72 10.29 10.43 885 735 215 1239 22.07 11.52 10.54 890 735 215 1246 22.50 11.52 10.98 895 735 215 1253 22.94 11.52 11.41 900 735 215 1260 23.36 11.52 11.84 900 728 217 1248 22.63 10.70 11.93 900 721 219 1236 21.88 9.88 12.00 900 714 221 1224 21.11 9.05 12.06 905 735 215 1267 23.79 11.52 12.27 903 725 218 1247 22.57 10.29 12.28 910 720 219 1248 22.63 9.88 12.75 925 714 221 1258 23.24 9.05 14.19 table a-10. overscan values, 800 x 600 ntsc, pixel-based controller, 1-pixel resolution (4 of 4) controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical resolution
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-25 table a-11. overscan values, 800 x 600 ntsc, character cloc k-based controller, 8-pixel resolution, 0?1.5 s hblank controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical resolution 800 777 203 1184 18.45 16.46 1.98 800 819 193 1248 22.63 20.58 2.05 800 798 198 1216 20.59 18.52 2.07 800 756 209 1152 16.18 13.99 2.19 800 714 221 1088 11.25 9.05 2.20 800 735 215 1120 13.79 11.52 2.26 840 780 202 1248 22.63 16.87 5.76 840 785 201 1256 23.12 17.28 5.84 840 765 206 1224 21.11 15.23 5.88 840 790 200 1264 23.61 17.70 5.91 840 750 210 1200 19.53 13.58 5.95 840 770 205 1232 21.62 15.64 5.99 840 755 209 1208 20.07 13.99 6.07 840 775 204 1240 22.13 16.05 6.08 840 740 213 1184 18.45 12.35 6.10 840 760 208 1216 20.59 14.40 6.19 840 730 216 1168 17.33 11.11 6.22 840 745 212 1192 18.99 12.76 6.24 840 720 219 1152 16.18 9.88 6.30 840 735 215 1176 17.89 11.52 6.37 840 725 218 1160 16.76 10.29 6.47 840 715 221 1144 15.59 9.05 6.54 880 735 215 1232 21.62 11.52 10.10
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-26 conexant 100381b table a-12. overscan values, 800 x 600 ntsc, character clock-based controller, 9-pixel resolution, 0?3.0 s hblank controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical resolution 810 805 196 1242 22.25 19.34 2.91 810 770 205 1188 18.72 15.64 3.08 810 735 215 1134 14.85 11.52 3.33 819 800 197 1248 22.63 18.93 3.70 819 750 210 1170 17.47 13.58 3.89 819 775 204 1209 20.13 16.05 4.08 819 725 218 1131 14.62 10.29 4.34 855 770 205 1254 23.00 15.64 7.36 855 735 215 1197 19.33 11.52 7.81 882 750 210 1260 23.36 13.58 9.78 882 725 218 1218 20.72 10.29 10.43 900 735 215 1260 23.36 11.52 11.84 900 728 217 1248 22.63 10.70 11.93 900 721 219 1236 21.88 9.88 12.00 900 714 221 1224 21.11 9.05 12.06
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-27 table a-13. overscan values 800 x 600 ntsc, pixel-based controller, 1-pixel resolution, 3:2 clocking mode (1 of 4) controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical delta 1170 770 205 1144 15.59 15.64 ? 0.04 1170 735 215 1092 11.57 11.52 0.05 1170 805 196 1196 19.26 19.34 ? 0.08 1176 750 210 1120 13.79 13.58 0.21 1176 825 191 1232 21.62 21.40 0.22 1175 756 209 1128 14.40 13.99 0.40 1175 819 193 1222 20.98 20.58 0.41 1155 795 199 1166 17.19 18.11 ? 0.92 1155 810 195 1188 18.72 19.75 ? 1.03 1155 735 215 1078 10.43 11.52 ? 1.10 1185 735 215 1106 12.69 11.52 1.17 1155 825 191 1210 20.20 21.40 ? 1.20 1190 765 206 1156 16.47 15.23 1.24 1155 780 202 1144 15.59 16.87 ? 1.28 1155 765 206 1122 13.94 15.23 ? 1.29 1150 819 193 1196 19.26 20.58 ? 1.31 1190 810 195 1224 21.11 19.75 1.36 1155 750 210 1100 12.22 13.58 ? 1.36 1190 720 219 1088 11.25 9.88 1.37 1150 756 209 1104 12.54 13.99 ? 1.46 1197 800 197 1216 20.59 18.93 1.66 1197 750 210 1140 15.30 13.58 1.72 1197 775 204 1178 18.03 16.05 1.98 1200 777 203 1184 18.45 16.46 1.98 1200 798 198 1216 20.59 18.52 2.07 1197 725 218 1102 12.38 10.29 2.09 1200 756 209 1152 16.18 13.99 2.19 1200 714 221 1088 11.25 9.05 2.20 1200 735 215 1120 13.79 11.52 2.26 1140 735 215 1064 9.25 11.52 ? 2.27
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-28 conexant 100381b 1134 775 204 1116 13.48 16.05 ? 2.57 1134 825 191 1188 18.72 21.40 ? 2.68 1134 800 197 1152 16.18 18.93 ? 2.75 1134 750 210 1080 10.59 13.58 ? 2.99 1215 770 205 1188 18.72 15.64 3.08 1125 819 193 1170 17.47 20.58 ? 3.11 1125 791 200 1130 14.55 17.70 ? 3.15 1218 750 210 1160 16.76 13.58 3.18 1125 798 198 1140 15.30 18.52 ? 3.22 1125 826 191 1180 18.17 21.40 ? 3.23 1125 805 196 1150 16.03 19.34 ? 3.31 1215 735 215 1134 14.85 11.52 3.33 1125 756 209 1080 10.59 13.99 ? 3.40 1125 763 207 1090 11.41 14.81 ? 3.40 1125 812 194 1160 16.76 20.16 ? 3.41 1125 749 211 1070 9.76 13.17 ? 3.41 1125 770 205 1100 12.22 15.64 ? 3.42 1125 777 203 1110 13.01 16.46 ? 3.45 1125 784 201 1120 13.79 17.28 ? 3.50 1225 792 199 1232 21.62 18.11 3.52 1120 810 195 1152 16.18 19.75 ? 3.57 1225 765 206 1190 18.86 15.23 3.63 1225 747 211 1162 16.90 13.17 3.73 1225 774 204 1204 19.80 16.05 3.75 1225 783 202 1218 20.72 16.87 3.85 1225 756 209 1176 17.89 13.99 3.90 1225 720 219 1120 13.79 9.88 3.91 1225 738 214 1148 15.89 11.93 3.95 1120 765 206 1088 11.25 15.23 ? 3.98 1225 729 217 1134 14.85 10.70 4.15 table a-13. overscan values 800 x 600 ntsc, pixel-based controller, 1-pixel resolution, 3:2 clocking mode (2 of 4) controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical delta
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-29 1113 825 191 1166 17.19 21.40 ? 4.21 1230 735 215 1148 15.89 11.52 4.37 1239 750 210 1180 18.17 13.58 4.59 1100 819 193 1144 15.59 20.58 ? 4.98 1245 735 215 1162 16.90 11.52 5.38 1250 756 209 1200 19.53 13.99 5.54 1092 825 191 1144 15.59 21.40 ? 5.81 1260 765 206 1224 21.11 15.23 5.88 1260 750 210 1200 19.53 13.58 5.95 1260 770 205 1232 21.62 15.64 5.99 1260 755 209 1208 20.07 13.99 6.07 1260 740 213 1184 18.45 12.35 6.10 1260 760 208 1216 20.59 14.40 6.19 1260 730 216 1168 17.33 11.11 6.22 1260 745 212 1192 18.99 12.76 6.24 1085 810 195 1116 13.48 19.75 ? 6.28 1260 720 219 1152 16.18 9.88 6.30 1260 735 215 1176 17.89 11.52 6.37 1260 725 218 1160 16.76 10.29 6.47 1260 715 221 1144 15.59 9.05 6.54 1080 805 196 1104 12.54 19.34 ? 6.81 1075 819 193 1118 13.63 20.58 ? 6.95 1275 756 209 1224 21.11 13.99 7.12 1281 750 210 1220 20.85 13.58 7.27 1275 735 215 1190 18.86 11.52 7.33 1275 714 221 1156 16.47 9.05 7.42 1071 825 191 1122 13.94 21.40 ? 7.46 1071 800 197 1088 11.25 18.93 ? 7.68 1290 735 215 1204 19.80 11.52 8.28 1295 720 219 1184 18.45 9.88 8.57 1050 828 191 1104 12.54 21.40 ? 8.86 table a-13. overscan values 800 x 600 ntsc, pixel-based controller, 1-pixel resolution, 3:2 clocking mode (3 of 4) controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical delta
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-30 conexant 100381b 1050 816 194 1088 11.25 20.16 ? 8.92 1050 831 190 1108 12.85 21.81 ? 8.96 1050 819 193 1092 11.57 20.58 ? 9.00 1050 807 196 1076 10.26 19.34 ? 9.08 1050 822 192 1096 11.90 20.99 ? 9.09 1050 810 195 1080 10.59 19.75 ? 9.16 1050 825 191 1100 12.22 21.40 ? 9.18 1305 735 215 1218 20.72 11.52 9.20 1050 813 194 1084 10.92 20.16 ? 9.24 1050 798 198 1064 9.25 18.52 ? 9.27 1050 801 197 1068 9.59 18.93 ? 9.34 1050 804 196 1072 9.92 19.34 ? 9.42 1320 735 215 1232 21.62 11.52 10.10 1323 725 218 1218 20.72 10.29 10.43 1330 720 219 1216 20.59 9.88 10.72 1029 825 191 1078 10.43 21.40 ? 10.97 1025 819 193 1066 9.42 20.58 ? 11.16 1350 721 219 1236 21.88 9.88 12.00 1350 714 221 1224 21.11 9.05 12.06 table a-13. overscan values 800 x 600 ntsc, pixel-based controller, 1-pixel resolution, 3:2 clocking mode (4 of 4) controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical delta
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-31 table a-14. overscan values 800 x 600 ntsc, character cl ocked-based controller, 8-pixel resolution, 3:2 clocking mode controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical delta 1176 750 210 1120 13.79 13.58 0.21 1176 825 191 1232 21.62 21.40 0.22 1200 777 203 1184 18.45 16.46 1.98 1200 798 198 1216 20.59 18.52 2.07 1200 756 209 1152 16.18 13.99 2.19 1200 714 221 1088 11.25 9.05 2.20 1200 735 215 1120 13.79 11.52 2.26 1120 810 195 1152 16.18 19.75 ? 3.57 1120 765 206 1088 11.25 15.23 ? 3.98 1080 805 196 1104 12.54 19.34 ? 6.81 1320 735 215 1232 21.62 11.52 10.10
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-32 conexant 100381b table a-15. overscan values 800 x 600 ntsc, character cl ocked-based controller, 9-pixel resolution, 3:2 clocking mode (1 of 2) controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical delta 1170 770 205 1144 15.59 15.64 ? 0.04 1170 735 215 1092 11.57 11.52 0.05 1170 805 196 1196 19.26 19.34 ? 0.08 1197 800 197 1216 20.59 18.93 1.66 1197 750 210 1140 15.30 13.58 1.72 1197 775 204 1178 18.03 16.05 1.98 1197 725 218 1102 12.38 10.29 2.09 1134 775 204 1116 13.48 16.05 ? 2.57 1134 825 191 1188 18.72 21.40 ? 2.68 1134 800 197 1152 16.18 18.93 ? 2.75 1134 750 210 1080 10.59 13.58 ? 2.99 1215 770 205 1188 18.72 15.64 3.08 1125 819 193 1170 17.47 20.58 ? 3.11 1125 791 200 1130 14.55 17.70 ? 3.15 1125 798 198 1140 15.30 18.52 ? 3.22 1125 826 191 1180 18.17 21.40 ? 3.23 1125 805 196 1150 16.03 19.34 ? 3.31 1215 735 215 1134 14.85 11.52 3.33 1125 756 209 1080 10.59 13.99 ? 3.40 1125 763 207 1090 11.41 14.81 ? 3.40 1125 812 194 1160 16.76 20.16 ? 3.41 1125 749 211 1070 9.76 13.17 ? 3.41 1125 770 205 1100 12.22 15.64 ? 3.42 1125 777 203 1110 13.01 16.46 ? 3.45 1125 784 201 1120 13.79 17.28 ? 3.50 1260 765 206 1224 21.11 15.23 5.88 1260 750 210 1200 19.53 13.58 5.95 1260 770 205 1232 21.62 15.64 5.99 1260 755 209 1208 20.07 13.99 6.07 1260 740 213 1184 18.45 12.35 6.10
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-33 1260 760 208 1216 20.59 14.40 6.19 1260 730 216 1168 17.33 11.11 6.22 1260 745 212 1192 18.99 12.76 6.24 1260 720 219 1152 16.18 9.88 6.30 1260 735 215 1176 17.89 11.52 6.37 1260 725 218 1160 16.76 10.29 6.47 1260 715 221 1144 15.59 9.05 6.54 1080 805 196 1104 12.54 19.34 ? 6.81 1071 825 191 1122 13.94 21.40 ? 7.46 1071 800 197 1088 11.25 18.93 ? 7.68 1305 735 215 1218 20.72 11.52 9.20 1323 725 218 1218 20.72 10.29 10.43 1350 721 219 1236 21.88 9.88 12.00 1350 714 221 1224 21.11 9.05 12.06 table a-15. overscan values 800 x 600 ntsc, character cl ocked-based controller, 9-pixel resolution, 3:2 clocking mode (2 of 2) controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical delta
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-34 conexant 100381b table a-16. overscan values, 800 x 600 pal-bdghi, pixel-based controller, 1-pixel resolution, >2.5 s hblank (1 of 2) controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical resolution 945 750 250 1134 13.17 13.19 ?0.02 950 750 250 1140 13.63 13.19 0.44 950 775 242 1178 16.42 15.97 0.44 940 750 250 1128 12.71 13.19 ?0.48 950 725 259 1102 10.65 10.07 0.58 950 800 235 1216 19.03 18.40 0.63 950 825 228 1254 21.48 20.83 0.65 955 750 250 1146 14.08 13.19 0.89 935 750 250 1122 12.24 13.19 ?0.95 960 750 250 1152 14.53 13.19 1.34 930 750 250 1116 11.77 13.19 ?1.42 925 825 228 1221 19.36 20.83 ?1.47 925 800 235 1184 16.84 18.40 ?1.56 965 750 250 1158 14.97 13.19 1.78 925 775 242 1147 14.16 15.97 ?1.81 925 750 250 1110 11.30 13.19 ?1.90 970 750 250 1164 15.41 13.19 2.22 920 750 250 1104 10.81 13.19 ?2.38 975 775 242 1209 18.56 15.97 2.59 975 750 250 1170 15.84 13.19 2.65 975 800 235 1248 21.10 18.40 2.70 915 750 250 1098 10.33 13.19 ?2.87 975 725 259 1131 12.94 10.07 2.87 980 750 250 1176 16.27 13.19 3.08 910 750 250 1092 9.83 13.19 ?3.36 985 750 250 1182 16.70 13.19 3.50 900 825 228 1188 17.12 20.83 ?3.71 905 750 250 1086 9.34 13.19 ?3.86 900 800 235 1152 14.53 18.40 ?3.87 990 750 250 1188 17.12 13.19 3.93 900 775 242 1116 11.77 15.97 ?4.20
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-35 995 750 250 1194 17.54 13.19 4.34 1000 785 239 1256 21.61 17.01 4.59 1000 775 242 1240 20.60 15.97 4.62 1000 750 250 1200 17.95 13.19 4.75 1000 780 241 1248 21.10 16.32 4.79 1000 760 247 1216 19.03 14.24 4.79 1000 770 244 1232 20.08 15.28 4.80 1000 745 252 1192 17.40 12.50 4.90 1000 730 257 1168 15.70 10.76 4.94 1000 755 249 1208 18.49 13.54 4.95 1000 765 246 1224 19.56 14.58 4.97 table a-16. overscan values, 800 x 600 pal-bdghi, pixel-based controller, 1-pixel resolution, >2.5 s hblank (2 of 2) controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical resolution
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-36 conexant 100381b table a-17. overscan values, 800 x 600 pal-bdghi, c haracter clock-based controller, 8-pixel resolution controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical resolution 960 750 250 1152 14.53 13.19 1.34 920 750 250 1104 10.81 13.19 ?2.38 1000 785 239 1256 21.61 17.01 4.59 1000 775 242 1240 20.60 15.97 4.62 1000 750 250 1200 17.95 13.19 4.75 1000 780 241 1248 21.10 16.32 4.79 1000 760 247 1216 19.03 14.24 4.79 1000 770 244 1232 20.08 15.28 4.80 1000 745 252 1192 17.40 12.50 4.90 1000 730 257 1168 15.70 10.76 4.94 1000 755 249 1208 18.49 13.54 4.95 1000 765 246 1224 19.56 14.58 4.97 1000 740 254 1184 16.84 11.81 5.03 1000 725 259 1160 15.12 10.07 5.05 1000 720 261 1152 14.53 9.38 5.15 1000 735 256 1176 16.27 11.11 5.16 1000 715 263 1144 13.93 8.68 5.25 1040 750 250 1248 21.10 13.19 7.91
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-37 table a-18. overscan values, 800 x 600 pal-bdghi, c haracter clock-based controller, 9-pixel resolution controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical resolution 945 750 250 1134 13.17 13.19 ?0.02 900 825 228 1188 17.12 20.83 ?3.71 900 800 235 1152 14.53 18.40 ?3.87 990 750 250 1188 17.12 13.19 3.93 900 775 242 1116 11.77 15.97 ?4.20 1035 750 250 1242 20.72 13.19 7.53
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-38 conexant 100381b table a-19. overscan values 800 x 600 pal-bdghi, pixel-bas ed controller, 1-pixel resolution, 3:2 clocking mode (1 of 3) controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical delta 1420 750 250 1136 13.33 13.19 0.13 1415 750 250 1132 13.02 13.19 ? 0.17 1425 750 250 1140 13.63 13.19 0.44 1425 775 242 1178 16.42 15.97 0.44 1410 750 250 1128 12.71 13.19 ? 0.48 1425 725 259 1102 10.65 10.07 0.58 1425 800 235 1216 19.03 18.40 0.63 1425 825 228 1254 21.48 20.83 0.65 1430 750 250 1144 13.93 13.19 0.74 1400 825 228 1232 20.08 20.83 ? 0.75 1405 750 250 1124 12.40 13.19 ? 0.79 1435 750 250 1148 14.23 13.19 1.04 1400 750 250 1120 12.09 13.19 ? 1.11 1440 750 250 1152 14.53 13.19 1.34 1395 750 250 1116 11.77 13.19 ? 1.42 1445 750 250 1156 14.83 13.19 1.63 1390 750 250 1112 11.46 13.19 ? 1.74 1450 750 250 1160 15.12 13.19 1.92 1385 750 250 1108 11.14 13.19 ? 2.06 1375 825 228 1210 18.63 20.83 ? 2.21 1455 750 250 1164 15.41 13.19 2.22 1375 810 232 1188 17.12 19.44 ? 2.32 1375 765 246 1122 12.24 14.58 ? 2.34 1380 750 250 1104 10.81 13.19 ? 2.38 1375 780 241 1144 13.93 16.32 ? 2.39 1375 795 236 1166 15.56 18.06 ? 2.50 1460 750 250 1168 15.70 13.19 2.51 1375 750 250 1100 10.49 13.19 ? 2.70 1465 750 250 1172 15.99 13.19 2.79 1370 750 250 1096 10.16 13.19 ? 3.03
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-39 1470 750 250 1176 16.27 13.19 3.08 1365 750 250 1092 9.83 13.19 ? 3.36 1475 750 250 1180 16.56 13.19 3.36 1480 750 250 1184 16.84 13.19 3.65 1360 750 250 1088 9.50 13.19 ? 3.69 1350 825 228 1188 17.12 20.83 ? 3.71 1350 800 235 1152 14.53 18.40 ? 3.87 1485 750 250 1188 17.12 13.19 3.93 1355 750 250 1084 9.17 13.19 ? 4.03 1350 775 242 1116 11.77 15.97 ? 4.20 1490 750 250 1192 17.40 13.19 4.20 1495 750 250 1196 17.67 13.19 4.48 1500 785 239 1256 21.61 17.01 4.59 1500 775 242 1240 20.60 15.97 4.62 1500 750 250 1200 17.95 13.19 4.75 1500 780 241 1248 21.10 16.32 4.79 1500 760 247 1216 19.03 14.24 4.79 1500 770 244 1232 20.08 15.28 4.80 1500 745 252 1192 17.40 12.50 4.90 1500 730 257 1168 15.70 10.76 4.94 1500 755 249 1208 18.49 13.54 4.95 1500 765 246 1224 19.56 14.58 4.97 1505 750 250 1204 18.22 13.19 5.03 1500 740 254 1184 16.84 11.81 5.03 1500 725 259 1160 15.12 10.07 5.05 1500 720 261 1152 14.53 9.38 5.15 1500 735 256 1176 16.27 11.11 5.16 1500 715 263 1144 13.93 8.68 5.25 1325 825 228 1166 15.56 20.83 ? 5.28 1510 750 250 1208 18.49 13.19 5.30 table a-19. overscan values 800 x 600 pal-bdghi, pixel-bas ed controller, 1-pixel resolution, 3:2 clocking mode (2 of 3) controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical delta
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-40 conexant 100381b 1515 750 250 1212 18.76 13.19 5.57 1520 750 250 1216 19.03 13.19 5.83 1525 750 250 1220 19.29 13.19 6.10 1530 750 250 1224 19.56 13.19 6.36 1535 750 250 1228 19.82 13.19 6.63 1540 750 250 1232 20.08 13.19 6.89 1300 825 228 1144 13.93 20.83 ? 6.90 1545 750 250 1236 20.34 13.19 7.14 1550 750 250 1240 20.60 13.19 7.40 1555 750 250 1244 20.85 13.19 7.66 1560 750 250 1248 21.10 13.19 7.91 1565 750 250 1252 21.36 13.19 8.16 1570 750 250 1256 21.61 13.19 8.41 1275 825 228 1122 12.24 20.83 ? 8.59 1575 750 250 1260 21.86 13.19 8.66 1275 800 235 1088 9.50 18.40 ? 8.90 1575 725 259 1218 19.16 10.07 9.09 1250 822 229 1096 10.16 20.49 ? 10.32 1250 825 228 1100 10.49 20.83 ? 10.34 1250 828 227 1104 10.81 21.18 ? 10.37 1250 831 226 1108 11.14 21.53 ? 10.39 1250 834 225 1112 11.46 21.88 ? 10.42 1250 813 231 1084 9.17 19.79 ? 10.62 1250 816 230 1088 9.50 20.14 ? 10.64 1250 819 229 1092 9.83 20.49 ? 10.65 1625 720 261 1248 21.10 9.38 11.73 table a-19. overscan values 800 x 600 pal-bdghi, pixel-bas ed controller, 1-pixel resolution, 3:2 clocking mode (3 of 3) controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical delta
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-41 table a-20. overscan values 800 x 600 pal-bdghi, character clock-based controller, 8-pixel resolution, 3:2 clocking mode controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical delta 1400 825 228 1232 20.08 20.83 ? 0.75 1400 750 250 1120 12.09 13.19 ? 1.11 1440 750 250 1152 14.53 13.19 1.34 1480 750 250 1184 16.84 13.19 3.65 1360 750 250 1088 9.50 13.19 ? 3.69 1520 750 250 1216 19.03 13.19 5.83 1560 750 250 1248 21.10 13.19 7.91 table a-21. overscan values 800 x 600 pal-bdghi, character clock-based controller, 9-pixel resolution, 3:2 clocking mode controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical delta 1440 750 250 1152 14.53 13.19 1.34 1395 750 250 1116 11.77 13.19 ? 1.42 1350 825 228 1188 17.12 20.83 ? 3.71 1350 800 235 1152 14.53 18.40 ? 3.87 1485 750 250 1188 17.12 13.19 3.93 1350 775 242 1116 11.77 15.97 ? 4.20 1530 750 250 1224 19.56 13.19 6.36 1575 750 250 1260 21.86 13.19 8.66 1575 725 259 1218 19.16 10.07 9.09
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-42 conexant 100381b table a-22. overscan values 1024 x 768 ntsc, pixel-based controller, 1-pixel resolution, >1.50 s. hblank (1 of 4) graphics controller encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical delta 1173 1050 192 1564 20.97 20.99 -0.01 1170 945 214 1404 11.97 11.93 0.03 1170 1015 199 1508 18.04 18.11 -0.07 1170 980 206 1456 15.11 15.23 -0.11 1175 1008 200 1504 17.82 17.7 0.13 1176 1050 192 1568 21.18 20.99 0.19 1170 1050 192 1560 20.77 20.99 -0.22 1176 975 207 1456 15.11 14.81 0.3 1165 945 214 1398 11.59 11.93 -0.34 1179 1050 192 1572 21.38 20.99 0.39 1175 945 214 1410 12.34 11.93 0.41 1167 1050 192 1556 20.57 20.99 -0.42 1182 1050 192 1576 21.58 20.99 0.59 1164 1050 192 1552 20.36 20.99 -0.63 1160 945 214 1392 11.21 11.93 -0.73 1180 945 214 1416 12.71 11.93 0.78 1185 1050 192 1580 21.77 20.99 0.79 1161 1050 192 1548 20.16 20.99 -0.83 1188 1050 192 1584 21.97 20.99 0.98 1158 1050 192 1544 19.95 20.99 -1.04 1155 945 214 1386 10.82 11.93 -1.11 1155 1005 201 1474 16.15 17.28 -1.14 1155 1020 198 1496 17.38 18.52 -1.14 1185 945 214 1422 13.08 11.93 1.15 1155 990 204 1452 14.88 16.05 -1.17 1155 1035 195 1518 18.58 19.75 -1.17 1190 1035 195 1564 20.97 19.75 1.22 1155 1050 192 1540 19.74 20.99 -1.25 1155 975 207 1430 13.57 14.81 -1.25 1155 930 217 1364 9.39 10.7 -1.31 1190 990 204 1496 17.38 16.05 1.33
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-43 1155 960 210 1408 12.22 13.58 -1.36 1152 1050 192 1536 19.53 20.99 -1.45 1150 945 214 1380 10.44 11.93 -1.5 1190 945 214 1428 13.45 11.93 1.51 1150 1008 200 1472 16.03 17.7 -1.66 1149 1050 192 1532 19.32 20.99 -1.66 1197 1025 197 1558 20.67 18.93 1.74 1197 975 207 1482 16.6 14.81 1.79 1197 925 218 1406 12.09 10.29 1.8 1197 1000 202 1520 18.69 16.87 1.81 1200 1029 196 1568 21.18 19.34 1.83 1200 1008 200 1536 19.53 17.7 1.84 1195 945 214 1434 13.81 11.93 1.88 1146 1050 192 1528 19.11 20.99 -1.88 1145 945 214 1374 10.05 11.93 -1.89 1200 966 209 1472 16.03 13.99 2.04 1197 950 213 1444 14.41 12.35 2.06 1143 1050 192 1524 18.9 20.99 -2.09 1200 987 205 1504 17.82 15.64 2.18 1200 945 214 1440 14.17 11.93 2.23 1140 945 214 1368 9.65 11.93 -2.28 1140 1050 192 1520 18.69 20.99 -2.3 1200 924 219 1408 12.22 9.88 2.34 1137 1050 192 1516 18.47 20.99 -2.52 1205 945 214 1446 14.52 11.93 2.59 1134 1025 197 1476 16.26 18.93 -2.67 1135 945 214 1362 9.25 11.93 -2.68 1134 950 213 1368 9.65 12.35 -2.69 1134 1000 202 1440 14.17 16.87 -2.7 1134 1050 192 1512 18.26 20.99 -2.73 1134 975 207 1404 11.97 14.81 -2.85 table a-22. overscan values 1024 x 768 ntsc, pixel-based controller, 1-pixel resolution, >1.50 s. hblank (2 of 4) graphics controller encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical delta
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-44 conexant 100381b 1210 945 214 1452 14.88 11.93 2.94 1215 1015 199 1566 21.07 18.11 2.97 1215 980 206 1512 18.26 15.23 3.03 1218 975 207 1508 18.04 14.81 3.22 1215 945 214 1458 15.23 11.93 3.29 1125 987 205 1410 12.34 15.64 -3.3 1125 973 208 1390 11.08 14.4 -3.32 1125 959 211 1370 9.78 13.17 -3.39 1225 1008 200 1568 21.18 17.7 3.48 1125 994 203 1420 12.96 16.46 -3.5 1125 980 206 1400 11.72 15.23 -3.51 1125 966 209 1380 10.44 13.99 -3.56 1225 999 202 1554 20.47 16.87 3.59 1125 952 212 1360 9.12 12.76 -3.64 1220 945 214 1464 15.58 11.93 3.64 1225 990 204 1540 19.74 16.05 3.69 1225 1017 199 1582 21.87 18.11 3.77 1225 981 206 1526 19.01 15.23 3.78 1225 972 208 1512 18.26 14.4 3.85 1225 963 210 1498 17.49 13.58 3.91 1225 954 212 1484 16.71 12.76 3.96 1225 918 220 1428 13.45 9.47 3.98 1225 945 214 1470 15.92 11.93 3.99 1225 927 218 1442 14.29 10.29 4 1225 936 216 1456 15.11 11.11 4 1230 945 214 1476 16.26 11.93 4.33 1239 975 207 1534 19.43 14.81 4.61 1235 945 214 1482 16.6 11.93 4.67 1240 945 214 1488 16.94 11.93 5 1245 945 214 1494 17.27 11.93 5.34 1250 945 214 1500 17.6 11.93 5.67 table a-22. overscan values 1024 x 768 ntsc, pixel-based controller, 1-pixel resolution, >1.50 s. hblank (3 of 4) graphics controller encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical delta
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-45 1260 990 204 1584 21.97 16.05 5.92 1260 985 205 1576 21.58 15.64 5.94 1260 980 206 1568 21.18 15.23 5.95 1260 960 210 1536 19.53 13.58 5.95 1260 975 207 1560 20.77 14.81 5.96 1260 965 209 1544 19.95 13.99 5.96 1260 970 208 1552 20.36 14.4 5.96 1255 945 214 1506 17.93 11.93 6 1260 925 218 1480 16.49 10.29 6.2 1260 930 217 1488 16.94 10.7 6.24 1260 935 216 1496 17.38 11.11 6.27 1260 940 215 1504 17.82 11.52 6.3 1260 945 214 1512 18.26 11.93 6.32 1260 950 213 1520 18.69 12.35 6.34 1260 955 212 1528 19.11 12.76 6.35 1260 915 221 1464 15.58 9.05 6.52 1260 920 220 1472 16.03 9.47 6.57 1265 945 214 1518 18.58 11.93 6.64 1270 945 214 1524 18.9 11.93 6.97 1275 966 209 1564 20.97 13.99 6.98 table a-22. overscan values 1024 x 768 ntsc, pixel-based controller, 1-pixel resolution, >1.50 s. hblank (4 of 4) graphics controller encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical delta
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-46 conexant 100381b table a-23. overscan values 1024 x 768 ntsc, character clock-based controller, 8-pixel resolution, >1.50 s hblank controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical delta 1176 1050 192 1568 21.18 20.99 0.19 1176 975 207 1456 15.11 14.81 0.30 1160 945 214 1392 11.21 11.93 ? 0.73 1152 1050 192 1536 19.53 20.99 ? 1.45 1200 1029 196 1568 21.18 19.34 1.83 1200 1008 200 1536 19.53 17.70 1.84 1200 966 209 1472 16.03 13.99 2.04 1200 987 205 1504 17.82 15.64 2.18 1200 945 214 1440 14.17 11.93 2.23 1200 924 219 1408 12.22 9.88 2.34 1240 945 214 1488 16.94 11.93 5.00 1280 945 214 1536 19.53 11.93 7.60 1320 945 214 1584 21.97 11.93 10.04 1176 1050 192 1568 21.18 20.99 0.19 1176 975 207 1456 15.11 14.81 0.30 1160 945 214 1392 11.21 11.93 ? 0.73 1152 1050 192 1536 19.53 20.99 ? 1.45 1200 1029 196 1568 21.18 19.34 1.83 1200 1008 200 1536 19.53 17.70 1.84 1200 966 209 1472 16.03 13.99 2.04 1200 987 205 1504 17.82 15.64 2.18 1200 945 214 1440 14.17 11.93 2.23 1200 924 219 1408 12.22 9.88 2.34 1128 1050 192 1504 17.82 20.99 ? 3.17 1240 945 214 1488 16.94 11.93 5.00 1280 945 214 1536 19.53 11.93 7.60
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-47 table a-24. overscan values 1024 x 768 ntsc, character clock-based controller, 9-pixel resolution (1 of 2) controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical delta 1170 945 214 1404 11.97 11.93 0.03 1170 1015 199 1508 18.04 18.11 ? 0.07 1170 980 206 1456 15.11 15.23 ? 0.11 1170 1050 192 1560 20.77 20.99 ? 0.22 1179 1050 192 1572 21.38 20.99 0.39 1161 1050 192 1548 20.16 20.99 ? 0.83 1188 1050 192 1584 21.97 20.99 0.98 1152 1050 192 1536 19.53 20.99 ? 1.45 1197 1025 197 1558 20.67 18.93 1.74 1197 975 207 1482 16.60 14.81 1.79 1197 925 218 1406 12.09 10.29 1.80 1197 1000 202 1520 18.69 16.87 1.81 1197 950 213 1444 14.41 12.35 2.06 1143 1050 192 1524 18.90 20.99 ? 2.09 1134 1025 197 1476 16.26 18.93 ? 2.67 1134 950 213 1368 9.65 12.35 ? 2.69 1134 1000 202 1440 14.17 16.87 ? 2.70 1134 1050 192 1512 18.26 20.99 ? 2.73 1134 975 207 1404 11.97 14.81 ? 2.85 1215 1015 199 1566 21.07 18.11 2.97 1215 980 206 1512 18.26 15.23 3.03 1215 945 214 1458 15.23 11.93 3.29 1125 987 205 1410 12.34 15.64 ? 3.30 1125 1001 202 1430 13.57 16.87 ? 3.30 1125 973 208 1390 11.08 14.40 ? 3.32 1125 959 211 1370 9.78 13.17 ? 3.39 1125 994 203 1420 12.96 16.46 ? 3.50 1125 980 206 1400 11.72 15.23 ? 3.51 1125 966 209 1380 10.44 13.99 ? 3.56 1125 952 212 1360 9.12 12.76 ? 3.64
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-48 conexant 100381b 1260 990 204 1584 21.97 16.05 5.92 1260 985 205 1576 21.58 15.64 5.94 1260 980 206 1568 21.18 15.23 5.95 1260 960 210 1536 19.53 13.58 5.95 1260 975 207 1560 20.77 14.81 5.96 1260 965 209 1544 19.95 13.99 5.96 1260 970 208 1552 20.36 14.40 5.96 1260 925 218 1480 16.49 10.29 6.20 1260 930 217 1488 16.94 10.70 6.24 1260 935 216 1496 17.38 11.11 6.27 1260 940 215 1504 17.82 11.52 6.30 1260 945 214 1512 18.26 11.93 6.32 1260 950 213 1520 18.69 12.35 6.34 1260 955 212 1528 19.11 12.76 6.35 1260 915 221 1464 15.58 9.05 6.52 1260 920 220 1472 16.03 9.47 6.57 table a-24. overscan values 1024 x 768 ntsc, character clock-based controller, 9-pixel resolution (2 of 2) controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical delta
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-49 table a-25. overscan values 1024 x 768 pal-bdghi, pixel-based controller, 1-pixel resolution, >3 s hblank (1 of 3) graphics controller encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical delta 1425 1000 240 1520 17.09 16.67 0.42 1410 1000 240 1504 16.2 16.67 -0.46 1425 1050 229 1596 21.03 20.49 0.55 1425 950 253 1444 12.72 12.15 0.57 1425 925 260 1406 10.36 9.72 0.64 1425 1025 235 1558 19.11 18.4 0.7 1425 975 247 1482 14.96 14.24 0.72 1400 975 247 1456 13.44 14.24 -0.8 1400 1050 229 1568 19.62 20.49 -0.86 1440 1000 240 1536 17.95 16.67 1.28 1395 1000 240 1488 15.3 16.67 -1.36 1455 1000 240 1552 18.79 16.67 2.13 1450 975 247 1508 16.43 14.24 2.19 1375 1065 226 1562 19.31 21.53 -2.21 1380 1000 240 1472 14.38 16.67 -2.29 1375 1020 236 1496 15.75 18.06 -2.3 1375 1050 229 1540 18.16 20.49 -2.32 1375 975 247 1430 11.87 14.24 -2.37 1375 990 243 1452 13.2 15.62 -2.42 1375 1035 232 1518 16.98 19.44 -2.47 1375 1005 239 1474 14.5 17.01 -2.52 1375 960 250 1408 10.49 13.19 -2.7 1375 945 254 1386 9.07 11.81 -2.74 1470 1000 240 1568 19.62 16.67 2.96 1365 1000 240 1456 13.44 16.67 -3.23 1475 975 247 1534 17.84 14.24 3.61 1485 1000 240 1584 20.44 16.67 3.77 1350 1025 235 1476 14.61 18.4 -3.79 1350 1050 229 1512 16.65 20.49 -3.84 1350 975 247 1404 10.23 14.24 -4 1350 1000 240 1440 12.48 16.67 -4.19
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-50 conexant 100381b 1500 1000 240 1600 21.23 16.67 4.56 1500 1005 239 1608 21.62 17.01 4.61 1500 1010 238 1616 22.01 17.36 4.65 1500 980 245 1568 19.62 14.93 4.69 1500 985 244 1576 20.03 15.28 4.75 1500 960 250 1536 17.95 13.19 4.75 1500 990 243 1584 20.44 15.62 4.81 1500 965 249 1544 18.37 13.54 4.83 1500 945 254 1512 16.65 11.81 4.84 1500 995 242 1592 20.83 15.97 4.86 1500 970 248 1552 18.79 13.89 4.91 1500 950 253 1520 17.09 12.15 4.93 1500 975 247 1560 19.21 14.24 4.97 1500 935 257 1496 15.75 10.76 4.99 1500 920 261 1472 14.38 9.38 5.01 1500 955 252 1528 17.52 12.5 5.02 1500 940 256 1504 16.2 11.11 5.09 1500 925 260 1480 14.84 9.72 5.12 1335 1000 240 1424 11.5 16.67 -5.17 1500 930 259 1488 15.3 10.07 5.23 1500 915 263 1464 13.91 8.68 5.23 1515 1000 240 1616 22.01 16.67 5.34 1325 1050 229 1484 15.07 20.49 -5.41 1320 1000 240 1408 10.49 16.67 -6.18 1525 975 247 1586 20.54 14.24 6.3 1300 1050 229 1456 13.44 20.49 -7.05 1305 1000 240 1392 9.46 16.67 -7.21 1550 975 247 1612 21.82 14.24 7.58 1275 1050 229 1428 11.74 20.49 -8.74 1275 1025 235 1394 9.59 18.4 -8.81 1575 950 253 1596 21.03 12.15 8.88 table a-25. overscan values 1024 x 768 pal-bdghi, pixel-based controller, 1-pixel resolution, >3 s hblank (2 of 3) graphics controller encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical delta
CX25870/871 appendix a scaling and i/0 timing register calculations flicker-free video encoder with ultrascale technology 100381b conexant a-51 1575 925 260 1554 18.9 9.72 9.18 1250 1065 226 1420 11.25 21.53 -10.2 1250 1056 228 1408 10.49 20.83 -10.3 1250 1068 225 1424 11.5 21.88 -10.3 1250 1047 230 1396 9.72 20.14 -10.4 1250 1059 227 1412 10.74 21.18 -10.4 1250 1038 232 1384 8.94 19.44 -10.5 1250 1050 229 1400 9.98 20.49 -10.5 1250 1062 226 1416 11 21.53 -10.5 1250 1041 231 1388 9.2 19.79 -10.5 1250 1053 228 1404 10.23 20.83 -10.6 1250 1044 230 1392 9.46 20.14 -10.6 1625 930 259 1612 21.82 10.07 11.75 1625 915 263 1586 20.54 8.68 11.85 table a-25. overscan values 1024 x 768 pal-bdghi, pixel-based controller, 1-pixel resolution, >3 s hblank (3 of 3) graphics controller encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical delta
appendix a scaling and i/0 timing register calculations CX25870/871 flicker-free video encoder with ultrascale technology a-52 conexant 100381b table a-26. 1024 x 768 pal-bdghi, character clock-based controller, 8-pixel resolution, >4 s hblank controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical delta 1400 975 247 1456 13.44 14.24 -0.8 1400 1050 229 1568 19.62 20.49 -0.86 1440 1000 240 1536 17.95 16.67 1.28 1320 1000 240 1408 10.49 16.67 -6.18 table a-27. overscan values 1024 x 768 pal-bdghi, c haracter clock-based controller, 9-pixel resolution controller pixels encoder pixels overscan (percent) total active total h_clki v_linesi v_activeo h_clko horizontal vertical delta 1440 1000 240 1536 17.95 16.67 1.28 1395 1000 240 1488 15.3 16.67 -1.36 1485 1000 240 1584 20.44 16.67 3.77 1350 1025 235 1476 14.61 18.4 -3.79 1350 1050 229 1512 16.65 20.49 -3.84 1350 975 247 1404 10.23 14.24 -4 1350 1000 240 1440 12.48 16.67 -4.19 1305 1000 240 1392 9.46 16.67 -7.21 1575 950 253 1596 21.03 12.15 8.88 1575 925 260 1554 18.9 9.72 9.18
100381b conexant b-1 b appendix b approved crystal vendors conexant conducted a series of internal tests and used the results to generate this list of approved crystal vendors for the CX25870/871. manufacturers not appearing in this list may be acceptable, but verification testing on the target pcb with samples is recommended. standard crystal (el monte, ca) phone number: (626) 443-2121 fax number: (626) 443-9049 e-mail: stdxtl@pacbell.net part numbers for 13.500 mhz, fundamental, 20 pf load crystal with an hc49u type of package: full height/50 ppm total tolerance: aal13m500000gxe20a half-height/50 ppm: aak13m500000gxe20a full height/25 ppm: did not qualify mmd components (irvine, ca) phone number: (949) 753-5888 fax number: (949) 753-5889 e-mail: info@mmdcomp.com internet: www.mmdcomp.com part numbers for 13.500 mhz, fundamental, 20 pf load crystal with an hc49u type of package: full height/50ppm total tolerance: a20ba1-13.500 mhz half-height/50 ppm: b20ba1-13.500 mhz full height/25 ppm: mmc-135-13.500 mhz (not tested) half height/25 ppm: mmc-136-13.500 mhz (not tested) general electronics devices (san marcos, ca) phone number: (760) 591-4170 fax number: (760) 591-4164 e-mail: gedlm@4dcomm.com internet: www.gedlm.com part numbers for 13.500 mhz, fundamental, 20 pf load crystal with an hc49u type of package: full height/50 ppm total tole rance: pkhc49-13.500-.020-.005 half-height/50 ppm: p khc49/-13.500-.020-.005 full height/25 ppm: pkhc49/-13.500-.020-.0025-15r half-height/25 ppm: p khc49/-13.500-.020-.0025
appendix b approved crystal vendors CX25870/871 flicker-free video encoder with ultrascale technology b-2 conexant 100381b fox electronics (fort myers, fl) phone number: (941) 693-0099 fax number: (941) 693-1554 e-mail: sales@foxonline.com internet: www.f oxonline.com part numbers for 13.500 mhz, fundamental, 20 pf load crystal with an hc49u type of package: full-height/50 ppm total tolerance: hc49u-13.500 /50/0/70/20 pf half-height/50 ppm: hc49s-13.500/50/0/70/20 pf full-height/25 ppm: hc49u-13.500 /25/0/70/20 pf half-height/25 ppm: hc49s-13.500 /25/0/70/20 pf (not tested) bomar crystal co. (middlesex, nj) phone number: (732) 356-7787 fax number: (732) 356-7362 e-mail: sales@bomarcrystal.com internet: www.bomarcrystal.com part numbers for 13.500 mhz, fundamental, 20 pf load crystal with an hc49u type of package: full height/50 ppm total to lerance: brc1c14f-13.50000 or (bc1dda120-13.50000) half height/50 ppm: acr-49s012025-13.50000 or (bc14dda120-13.50000) full height/25 ppm: brcih14f-13.50000 or (bc1aaa120-13.50000 half height/25 ppm: bc14aaa120-13.50000 (not tested) ilsi america (reno, nv) phone number: (775) 8 51-8880x103 / (888)355-4574 fax number: (775) 851-8882 e-mail: e-mail@ilsiamerica.com internet: www.ilsiamerica.com part numbers for 13.500 mhz, fundamental, 20 pf load crystal with an hc49u type of package: full height/50 ppm total tolerance: hc49u-25/25-13.500-20 half height/50 ppm: hc49us-fb1f20-13.500 full height/25 ppm: did not qualify
CX25870/871 appendix b approved crystal vendors flicker-free video encoder with ultrascale technology 100381b conexant b-3 cardinal components (wayne, nj) phone number: (973) 785-1333 fax number: (973) 785-0053 e-mail: cardinal@cardinalxtal.com internet: www.cardinalxtal.com part numbers for 13.500 mhz, fundamental, 20 pf load crystal with an hc49u type of package: full height/50 ppm total to lerance: c49-a4brc7-50-13.5d20 half height/50 ppm: c lp-a4brc7-70-13.5d20 full height/25 ppm: c49-a4b6c4-25-13.5d20 half height/25 ppm clp-a4b6c4-25-13.5d20 raltron electronics corp. (miami, fl) phone number: (305) 593-6033 fax number: (305) 594-3973 e-mail: sales@raltron.com internet: www.raltron.com part numbers for 13.500 mhz, fundamental, 20 pf load crystal with an hc49u type of package: full height/50 ppm total tolerance: a-13.500-20-rs1 half height/50 ppm: as-13.500-20-rs1 full height/25 ppm: a-13.500-20-rs1 half height/25ppm: as-13.500-20-smd-nv valpey-fisher (hopkinton, ma) phone number: (508) 435-6831 fax number: (508) 435-5289 internet: www.valpeyfisher.com part numbers for 13.500 mhz, fundamental, 20 pf load crystal with an hc49u type of package: full height/50 ppm total tolerance: m490013.500020rsvm half height/50 ppm: m49k013.50002099vm full height/25 ppm: m490013.50002099vm corning frequency control (mount holly springs, pa) phone number: (717) 486-3411 fax number:(717) 486-5920 e-mail: sales@ofc.come internet: www.corningfrequency.com part numbers for 13.500 mhz, fundamental, 20 pf load crystal with an hc49u type of package: full height/50 ppm total tolerance: tq rsd 13.5fh50 half height/50 ppm: tq rsd 13.5lp50 full height/25 ppm: tq rsd 13.5fh25 half height/25 ppm: tq rsd 13.5lp25 (not tested)
appendix b approved crystal vendors CX25870/871 flicker-free video encoder with ultrascale technology b-4 conexant 100381b
100381b conexant c-1 c appendix c autoconfiguration mode register values and details table c-1. CX25870/871 register values for autoconfiguration modes 0?4 (1 of 3) autoconfiguration mode # 0 1 2 3 4 auto-config register (index 0xb8) hexadecimal value: 00 01 02 03 04 purpose of mode: desktop de sktop desktop desktop desktop type of digital input: rgb rgb rgb rgb ycrcb active resolution: 640x 480 640x480 800x600 800x600 640x480 overscan ratio: lower standard alternate lower lower horizontal overscan ratio/percentage (hoc): 13.79 16.56 21.62 14.53 13.79 vertical overscan ratio/percentage (voc): 13.58 16.67 11.52 13.19 13.58 overscan percentages delta (hoc - voc): 0.21 ?0.11 10.10 1.34 0.21 h_clki = htotal 784 944 880 960 784 vlines_i = vtotal 600 625 735 750 600 h_blanki = horizontal blanking region 126 266 66 140 126 v_blanki = vertical blanking region 75 90 86 95 75 type of video output: ntsc p al-bdghi ntsc pal-bdghi ntsc frequency of clk (hz) 28195793 29500008 38769241 36000000 28195793 type of clock: pixel or character pixel or character pixel or character pixel or character pixel or character
appendix c autoconfiguration mode register values and details CX25870/871 flicker-free video encoder with ultrascale technology c-2 conexant 100381b register address register value register value register value register value register value 0x38 00 00 00 00 00 0x76 00 60 a0 00 00 0x78 80 80 20 20 80 0x7a 84 8a b6 aa 84 0x7c 96 a6 ce ca 96 0x7e 60 68 b4 9a 60 0x80 7d c1 55 0d 7d 0x82 22 2e 20 29 22 0x84 d4 f2 d8 fc d4 0x86 27 27 39 39 27 0x88 00 00 00 00 00 0x8a 10 b0 70 c0 10 0x8c 7e 0a 42 8c 7e 0x8e 03 0b 03 03 03 0x90 58 71 df ee 58 0x92 4b 5a 56 5f 4b 0x94 e0 e0 58 58 e0 0x96 36 36 3a 3a 36 0x98 92 00 cd 66 92 0x9a 54 50 9c 96 54 0x9c 0e 72 14 00 0e 0x9e 88 1c 3b 00 88 0xa0 0c 0d 11 10 0c 0xa2 0a 24 0a 24 0a 0xa4 e5 f0 e5 f0 e5 0xa6 76 58 74 57 76 0xa8 79 81 77 80 79 0xaa 44 49 43 48 44 0xac 85 8c 85 8c 85 0xae 00 0c ba 18 00 table c-1. CX25870/871 register values for autoconfiguration modes 0?4 (2 of 3) autoconfiguration mode # 0 1 2 3 4
CX25870/871 appendix c autoconfiguration mode register values and details flicker-free video encoder with ultrascale technology 100381b conexant c-3 0xb0 00 8c e8 28 00 0xb2 80 79 a2 87 80 0xb4 20 26 17 1f 20 note(s): 1. rgb digital input denotes that the CX25870/871 will be configured to receiv e the rgb default pixel input mode after an autoconfiguration command which is 24-bi t, rgb-multiplexed (i.e., in_mode[3:0] = 0000). if th e desired rgb pixel input mode is not 24-bit rgb-multiplexed, the CX25870/871's in_mode[3:0] bi ts must be programmed to the desired rgb pixel input mode immediately before initia ting a write to the config[5:0] bits. 2. ycrcb digital input denotes th at the CX25870/871 will be confi gured to receive ycrc b pixel data after an autoconfiguration command. the CX25870/871's in_m ode[3:0] bits must be programmed to the desired ycrcb pixel i nput mode immediately before initiating a write to the config[5:0] bits. 3. CX25870/871 registers not listed in this table (including in_mode[3:0]) do not get reprogrammed as a result of an autoconfiguration command. 4. pixel or character signifies that this overscan ratio is acce ptable for 8-clock per character graphics controllers or pixel-c lock controllers. 5. the CX25870/871 will be in master interf ace immediatel y after any autoconfiguration m ode except mode 28 and mode 29. 6. mode 44 would ideally have 858 clocks pe r line. however, since 858 is not a multiple of 8, then 880 clocks per line was utilized instead. 7. these autoconfiguration valu es assume a 13.500 mhz crysta l resides between the xtalin and xtalout pins. if the 14318_xtal bit is set, then these autoconfigur ation values will automati cally change to reflect th e presence of a 14.318 mhz crystal. table c-1. CX25870/871 register values for autoconfiguration modes 0?4 (3 of 3) autoconfiguration mode # 0 1 2 3 4
appendix c autoconfiguration mode register values and details CX25870/871 flicker-free video encoder with ultrascale technology c-4 conexant 100381b table c-2. CX25870/871 register values for autoconfiguration modes 5?10 (1 of 2) autoconfiguration mode # 5 6 7 8 9 10 auto-config register (index 0xb8) hexadecimal value: 05 06 07 10 11 12 purpose of mode: desktop desktop desktop boot-up screen boot-up screen desktop type of digital input: ycrcb ycrcb ycrcb rgb rgb rgb active resolution: 640x480 800x600 800x600 640x400 640x400 1024x768 overscan ratio: standard alternat e lower standard st andard standard horizontal overscan ratio/percentage (hoc): 16.56 21.62 14.53 17.47 15.12 15.11 vertical overscan ratio/percentage (voc): 16.67 11.52 13.19 17.70 13.19 14.81 overscan percentages delta (hoc - voc): ?0.11 10.10 1.34 ?0.23 1.93 0.30 h_clki = htotal 944 880 960 936 1160 1176 vlines_i = vtotal 625 735 750 525 500 975 h_blanki = horizontal blanking region 266 66 140 259 363 133 v_blanki = vertical blanking region 90 86 95 76 64 130 type of video output: pal-bdghi ntsc pal-bdghi ntsc pal-bdghi ntsc frequency of clk (hz) 29500008 38769241 36000000 29454552 28999992 68727276 type of clock: pixel or character pixel or character pixel or character pixel or character pixel or character pixel or character register address register value register value register value register value register value register value 0x38 00 00 00 00 00 20 0x76 60 a0 00 50 40 60 0x78 80 20 20 80 80 00 0x7a 8a b6 aa 8a 88 d8 0x7c a6 ce ca 9c a2 f2 0x7e 68 b4 9a 6a 64 ee 0x80 c1 55 0d a9 af 71 0x82 2e 20 29 27 29 24 0x84 f2 d8 fc ca fc d0 0x86 27 39 39 27 27 4b 0x88 00 00 00 00 00 00 0x8a b0 70 c0 a8 88 98
CX25870/871 appendix c autoconfiguration mode register values and details flicker-free video encoder with ultrascale technology 100381b conexant c-5 0x8c 0a 42 8c 03 6b 85 0x8e 0b 03 03 0b 0c 04 0x90 71 df ee 0d f4 cf 0x92 5a 56 5f 4c 40 82 0x94 e0 58 58 90 90 00 0x96 36 3a 3a 36 35 3f 0x98 00 cd 66 00 9a 6e 0x9a 50 9c 96 50 49 ab 0x9c 72 14 00 46 8e a3 0x9e 1c 3b 00 17 e3 8b 0xa0 0d 11 10 0d 0c 1e 0xa2 24 0a 24 0a 24 0a 0xa4 f0 e5 f0 e5 f0 e5 0xa6 58 74 57 75 58 74 0xa8 81 77 80 79 82 77 0xaa 49 43 48 44 49 43 0xac 8c 85 8c 85 8c 85 0xae 0c ba 18 c7 e9 00 0xb0 8c e8 28 71 5d 00 0xb2 79 a2 87 1c 23 00 0xb4 26 17 1f 1f 27 14 note(s): 1. rgb digital input denotes that the CX25870/871 will be configured to receiv e the rgb default pixel input mode after an autoconfiguration command, which is 24-bi t, rgb-multiplexed (i.e., in_mode[3:0] = 0000). if the desired rgb pixel input mode is not 24-bit rgb-multiplexed, th e CX25870/871's in_mode[3:0] bi ts must be programmed to the desired rgb pixel input mode immediately before initia ting a write to the config[5:0] bits. 2. ycrcb digital input denotes th at the CX25870/871 will be confi gured to receive ycrc b pixel data after an autoconfiguration command. the CX25870/871's in_mode[3:0] bits must be programmed to the desire d ycrcb pixel input mode immediately before initiating a write to the config[5:0] bits. 3. CX25870/871 registers not listed in this table (including in_mode[3:0]) do not get reprogrammed as a result of an autoconfiguration command. 4. pixel or character signifies that this overscan ratio is acce ptable for 8-clock per character graphics controllers or pixel-c lock controllers. 5. the CX25870/871 will be in master interf ace immediatel y after any autoconfiguration m ode except mode 28 and mode 29. 6. mode 44 would ideally have 858 clocks pe r line. however, since 858 is not a multiple of 8, then 880 clocks per line was utilized instead. 7. these autoconfiguration valu es assume a 13.500 mhz crysta l resides between the xtalin and xtalout pins. if the 14318_xtal bit is set, then these autoconfigur ation values will automati cally change to reflect th e presence of a 14.318 mhz crystal. table c-2. CX25870/871 register values for autoconfiguration modes 5?10 (2 of 2) autoconfiguration mode # 5 6 7 8 9 10
appendix c autoconfiguration mode register values and details CX25870/871 flicker-free video encoder with ultrascale technology c-6 conexant 100381b table c-3. CX25870/871 register values for autoconfiguration modes 11?15 (1 of 2) autoconfiguration mode # 11 12 13 14 15 auto-config register (index 0xb8) hexadecimal value: 13 14 15 16 17 purpose of mode: desktop game game desktop desktop type of digital input: rgb rgb rgb ycrcb ycrcb active resolution: 1024x768 320x240, pix_double set 320x240, pix_double set 1024x768 1024x768 overscan ratio: standard st andard standard higher higher horizontal overscan ratio/percentage (hoc): 13.44 13.79 15.84 15.11 13.44 vertical overscan ratio/percentage (voc): 14.24 13.58 19.79 14.81 14.24 overscan percentages delta (hoc - voc): ?0.80 0.21 ?3.95 0.30 ?0.80 h_clki = htotal 1400 1568 1800 1176 1400 vlines_i = vtotal 975 300 325 975 975 h_blanki = horizontal blanking region 329 349 385 133 329 v_blanki = vertical blanking region 131 37 50 130 131 type of video output: pal-bdg hi ntsc pal-bdghi ntsc pal-bdghi frequency of clk (hz) 68249989 28195793 29250000 68727276 68249989 type of clock: pixel or character pixel or character pixel or character pixel or character pixel or character register address register value register value register value register value register value 0x38 20 40 40 20 20 0x76 60 00 50 60 60 0x78 00 80 80 00 00 0x7a d6 84 8a d8 d6 0x7c fe 96 a4 f2 fe 0x7e e6 60 66 ee e6 0x80 87 7d b7 71 87 0x82 2b 22 32 24 2b 0x84 f8 d5 ea d0 f8 0x86 4b 27 27 4b 4b 0x88 00 00 00 00 00 0x8a 78 20 08 98 78
CX25870/871 appendix c autoconfiguration mode register values and details flicker-free video encoder with ultrascale technology 100381b conexant c-7 0x8c 49 5d 81 85 49 0x8e 0d 1e 1f 04 0d 0x90 cf 2c 45 cf cf 0x92 83 25 32 82 83 0x94 00 f0 f0 00 00 0x96 3f 31 31 3f 3f 0x98 ec 49 a4 6e ec 0x9a a1 42 40 ab a1 0x9c 55 0e 00 a3 55 0x9e 55 88 00 8b 55 0xa0 1e 0c 0d 1e 1e 0xa2 24 0a 24 0a 24 0xa4 f0 e5 f0 e5 f0 0xa6 56 76 58 74 56 0xa8 7f 79 81 77 7f 0xaa 47 44 49 43 47 0xac 8c 85 8c 85 8c 0xae 57 00 32 00 57 0xb0 f8 00 bb 00 f8 0xb2 f1 80 cd 00 f1 0xb4 18 20 26 14 18 note(s): 1. rgb digital input denotes that the CX25870/871 will be configured to receiv e the rgb default pixel input mode after an autoconfiguration command, which is 24-bi t, rgb-multiplexed (i.e., in_mode[3:0] = 0000). if the desired rgb pixel input mode is not 24-bit rgb multiplexed, th e CX25870/871's in_mode[3: 0] bits must be programme d to the desired rgb pixel input mode immediately before initia ting a write to the config[5:0] bits. 2. ycrcb digital input denotes th at the CX25870/871 will be confi gured to receive ycrc b pixel data after an autoconfiguration command. the CX25870/871' s in_mode[3:0] bits must be programmed to the desired ycrcb pixel input mode immediately before initiating a write to the config[5:0] bits. 3. CX25870/871 registers not listed in this table (including in_mode[3:0]) do not get reprogrammed as a result of an autoconfiguration command. 4. pixel or character signifies that this overscan ratio is acce ptable for 8-clock per character graphics controlle rs or pixel-c lock controllers. 5. the CX25870/871 will be in master interf ace immediatel y after any autoconfiguration m ode except mode 28 and mode 29. 6. mode 44 would ideally have 858 clocks pe r line. however, since 858 is not a multiple of 8, then 880 clocks per line was utilized instead. 7. these autoconfiguration valu es assume a 13.500 mhz crysta l resides between the xtalin and xtalout pins. if the 14318_xtal bit is set, then these autoconfi guration values will au tomatically change to reflect the presence of a 14.318 mhz crystal. table c-3. CX25870/871 register values for autoconfiguration modes 11?15 (2 of 2) autoconfiguration mode # 11 12 13 14 15
appendix c autoconfiguration mode register values and details CX25870/871 flicker-free video encoder with ultrascale technology c-8 conexant 100381b table c-4. CX25870/871 register values for autoconfiguration modes 16?21 (1 of 2) autoconfiguration mode # 16 17 18 19 20 21 auto-config register (index 0xb8) hexadecimal value: reserved 21 22 23 reserved 25 purpose of mode: desktop desktop desktop desktop type of digital input: rgb rgb rgb ycrcb active resolution: 640x480 800x600 800x600 640x480 overscan ratio: lower lower standard lower horizontal overscan ratio/percentage (hoc): 13.63 13.79 16.42 13.63 vertical overscan ratio/percentage (voc): 13.19 13.58 15.97 13.19 overscan percentages delta (hoc - voc): 0.44 0.21 0.45 0.44 h_clki = htotal 950 1176 950 950 vlines_i = vtotal 600 750 775 600 h_blanki = horizontal blanking region 271 329 131 271 v_blanki = vertical blanking region 76 94 109 76 type of video output: pal-bdghi ntsc pal-bdghi pal-bdghi frequency of clk (hz) 28500011 52867138 36812508 28500011 type of clock: pi xel only pixel or character pixel only pixel only register address register value register value register value register value 0x38 00 20 00 00 0x76 20 c0 34 20 0x78 80 20 20 80 0x7a 86 a6 ae 86 0x7c a0 ba ce a0 0x7e 60 98 a0 60 0x80 9d d9 2b 9d 0x82 29 22 2d 29 0x84 fc d4 f4 fc 0x86 27 38 39 27 0x88 00 00 00 00 0x8a b6 98 b6 b6 0x8c 0f 49 83 0f
CX25870/871 appendix c autoconfiguration mode register values and details flicker-free video encoder with ultrascale technology 100381b conexant c-9 0x8e 0b 0c 03 0b 0x90 58 ee 07 58 0x92 4c 5e 6d 4c 0x94 e0 58 58 e0 0x96 36 3a 3b 36 0x98 b8 b7 ae b8 0x9a 4e 5d 97 4e 0x9c ab 1b 72 ab 0x9e aa 7f 5c aa 0xa0 0c 17 10 0c 0xa2 24 0a 24 24 0xa4 f0 e5 f0 f0 0xa6 58 74 57 58 0xa8 82 78 80 82 0xaa 49 43 48 49 0xac 8c 85 8c 8c 0xae 2c 00 01 2c 0xb0 25 00 04 25 0xb2 d3 00 d5 d3 0xb4 27 1a 1e 27 note(s): 1. rgb digital input denotes that the CX25870/871 will be configured to receiv e the rgb default pixel input mode after an autoconfiguration command, which is 24-bi t, rgb-multiplexed (i.e., in_mode[3:0] = 0000). if the desired rgb pixel input mode is not 24-bit rgb-multiplexed, th e CX25870/871's in_mode[3:0] bi ts must be programmed to the desired rgb pixel input mode immediately before initia ting a write to the config[5:0] bits. 2. ycrcb digital input denotes th at the CX25870/871 will be confi gured to receive ycrc b pixel data after an autoconfiguration command. the CX25870/871's in_mod e[3:0] bits must be programmed to the de sired ycrcb pixel input mode immediately before initiating a write to the config[5:0] bits. 3. CX25870/871 registers not listed in this table (including in_mode[ 3:0]) do not get reprogramme d as a result of an autoconfiguration command. 4. pixel or character signifies that this overscan ratio is acce ptable for 8-clock per character graphics controllers or pixel-c lock controllers. 5. the CX25870/871 will be in master interf ace immediatel y after any autoconfiguration m ode except mode 28 and mode 29. 6. mode 44 would ideally have 858 clocks pe r line. however, since 858 is not a multiple of 8, then 880 clocks per line was utilized instead. 7. these autoconfiguration valu es assume a 13.500 mhz crysta l resides between the xtalin and xtalout pins. if the 14318_xtal bit is set, then these autoconfi guration values will au tomatically change to reflect the presence of a 14.318 mhz crystal. table c-4. CX25870/871 register values for autoconfiguration modes 16?21 (2 of 2) autoconfiguration mode # 16 17 18 19 20 21
appendix c autoconfiguration mode register values and details CX25870/871 flicker-free video encoder with ultrascale technology c-10 conexant 100381b table c-5. CX25870/871 register values for autoconfiguration modes 22?26 (1 of 2) autoconfiguration mode # 22 23 24 25 26 auto-config register (index 0xb8) hexadecimal value: 26 27 30 31 32 purpose of mode: desktop desktop boot-up screen boot-up screen desktop type of digital input: ycrcb ycrcb rgb rgb rgb active resolution: 800x600 800x600 720x400 720x400 1024x768 overscan ratio: lower sta ndard standard standard lower horizontal overscan ratio/percentage (hoc): 13.79 16.42 17.47 15.12 11.97 vertical overscan ratio/percentage (voc): 13.58 15.97 17.70 13.19 11.93 overscan percentages delta (hoc - voc): 0.21 0.45 ?0.23 1.93 0.04 h_clki = htotal 1176 950 1053 1305 1170 vlines_i = vtotal 750 775 525 500 945 h_blanki = horizontal blanking region 329 131 291 411 127 v_blanki = vertical blanking region 94 109 76 64 115 type of video output: ntsc p al-bdghi ntsc pal-bdghi ntsc frequency of clk (hz) 52867138 36812508 33136345 32625000 66272724 type of clock: pixel or character pixel only pixel or 9-character only pixel or 9-character only pixel only register address register value register value register value register value register value 0x38 20 00 00 00 20 0x76 c0 34 3a 28 f8 0x78 20 20 d0 d0 00 0x7a a6 ae 9c 9a d0 0x7c ba ce b0 b6 ea 0x7e 98 a0 88 80 e0 0x80 d9 2b dd e3 37 0x82 22 2d 27 29 21 0x84 d4 f4 ca fc d7 0x86 38 39 28 28 4a 0x88 00 00 00 00 00
CX25870/871 appendix c autoconfiguration mode register values and details flicker-free video encoder with ultrascale technology 100381b conexant c-11 0x8a 98 b6 1d 19 92 0x8c 49 83 23 9b 7f 0x8e 0c 03 0c 0d 04 0x90 ee 07 0d f4 b1 0x92 5e 6d 4c 40 73 0x94 58 58 90 90 00 0x96 3a 3b 36 35 3f 0x98 b7 ae 00 9a 9a 0x9a 5d 97 50 49 a9 0x9c 1b 72 2e 00 5d 0x9e 7f 5c ba 80 74 0xa0 17 10 0e 0e 1d 0xa2 0a 24 0a 24 0a 0xa4 e5 f0 e5 f0 e5 0xa6 74 57 75 57 74 0xa8 78 80 78 80 77 0xaa 43 48 43 48 43 0xac 85 8c 85 8c 85 0xae 00 01 95 97 2f 0xb0 00 04 81 1a a1 0xb2 00 d5 a7 ca bd 0xb4 1a 1e 1b 22 14 note(s): 1. rgb digital input denotes that the CX25870/871 will be configured to receiv e the rgb default pixel input mode after an autoconfiguration command, which is 24-bi t, rgb-multiplexed (i.e., in_mode[3:0] = 0000). if the desired rgb pixel input mode is not 24-bit rgb multiplexed, th e CX25870/871's in_mode[3:0] bi ts must be programmed to the desired rgb pixel input mode immediately before initia ting a write to the config[5:0] bits. 2. ycrcb digital input denotes th at the CX25870/871 will be confi gured to receive ycrc b pixel data after an autoconfiguration command. the CX25870/871's in_m ode[3:0] bits must be programmed to the desired ycrcb pixel i nput mode immediately before initiating a write to the config[5:0] bits. 3. CX25870/871 registers not listed in this table (including in_mode[3:0]) do not get reprogrammed as a result of an autoconfiguration command. 4. pixel or character signifies that this overscan ratio is acce ptable for 8-clock per character graphics controllers or pixel-c lock controllers. 5. the CX25870/871 will be in master interf ace immediatel y after any autoconfiguration m ode except mode 28 and mode 29. 6. mode 44 would ideally have 858 clocks pe r line. however, since 858 is not a multiple of 8, then 880 clocks per line was utilized instead. 7. these autoconfiguration valu es assume a 13.500 mhz crysta l resides between the xtalin and xtalout pins. if the 14318_xtal bit is set, then these autoconfigur ation values will automati cally change to reflect th e presence of a 14.318 mhz crystal. table c-5. CX25870/871 register values for autoconfiguration modes 22?26 (2 of 2) autoconfiguration mode # 22 23 24 25 26
appendix c autoconfiguration mode register values and details CX25870/871 flicker-free video encoder with ultrascale technology c-12 conexant 100381b table c-6. CX25870/871 register values for autoconfiguration modes 27?30 (1 of 2) autoconfiguration mode # 27 28 (5) 29 (5) 30 auto-config register (index 0xb8) hexadecimal value: reserved 34 35 36 purpose of mode: "dvd/ccir601 input, slave interface" "dvd/ccir601 input, slave interface" desktop type of digital input: ycrcb ycrcb ycrcb active resolution: 720x480 720x576 1024x768 overscan ratio: none (dvd playback) none (dvd playback) lower horizontal overscan ratio/percentage (hoc): 0.00 0.00 11.97 vertical overscan ratio/percentage (voc): 0.00 0.00 11.93 overscan percentages delta (hoc - voc): 0.00 0.00 0.04 h_clki = htotal 858 864 1170 vlines_i = vtotal 262 312 945 h_blanki = horizontal blanking region 10 10 127 v_blanki = vertical blanking region 19 22 115 type of video output: ntsc pal-bdghi ntsc frequency of clk (hz) 27000000 27000000 66272724 type of clock: pixel or characte r pixel or character pixel only register address register value register value register value 0x38 10 10 20 0x76 b4 c0 f8 0x78 d0 d0 00 0x7a 7e 7e d0 0x7c 90 98 ea 0x7e 58 54 e0 0x80 03 15 37 0x82 14 17 21 0x84 f0 20 d7 0x86 26 a6 4a 0x88 15 fa 00 0x8a 5a 60 92 0x8c 0a 0a 7f
CX25870/871 appendix c autoconfiguration mode register values and details flicker-free video encoder with ultrascale technology 100381b conexant c-13 0x8e 13 13 04 0x90 06 38 b1 0x92 13 16 73 0x94 f0 20 00 0x96 31 35 3f 0x98 00 00 9a 0x9a 40 40 a9 0x9c 00 00 5d 0x9e 00 00 74 0xa0 8c 8c 1d 0xa2 0a 24 0a 0xa4 e5 f0 e5 0xa6 76 59 74 0xa8 c1 cf 77 0xaa 89 93 43 0xac 9a a4 85 0xae 1f cb 2f 0xb0 7c 8a a1 0xb2 f0 09 bd 0xb4 21 2a 14 note(s): 1. rgb digital input denotes that the CX25870/871 will be configured to receiv e the rgb default pixel input mode after an autoconfiguration command, which is 24-bi t, rgb-multiplexed (i.e., in_mode[3:0] = 0000). if the desired rgb pixel input mode is not 24-bit rgb multiplexed, th e CX25870/871's in_mode[3:0] bi ts must be programmed to the desired rgb pixel input mode immediately before initia ting a write to the config[5:0] bits. 2. ycrcb digital input denotes th at the CX25870/871 will be confi gured to receive ycrc b pixel data after an autoconfiguration command. the CX25870/871's in_m ode[3:0] bits must be programmed to the desired ycrcb pixel i nput mode immediately before initiating a write to the config[5:0] bits. 3. CX25870/871 registers not listed in this table (including in_mode[3:0]) do not get reprogrammed as a result of an autoconfiguration command. 4. pixel or character signifies that this overscan ratio is acce ptable for 8-clock per character graphics controllers or pixel-c lock controllers. (5) the CX25870/871 will be in master interfac e immediately af ter any autoconfiguration mode except mode 28 and mode 29. 6. mode 44 would ideally have 858 clocks pe r line. however, since 858 is not a multiple of 8, then 880 clocks per line was utilized instead. 7. these autoconfiguration valu es assume a 13.500 mhz crysta l resides between the xtalin and xtalout pins. if the 14318_xtal bit is set, then these autoconfigur ation values will automati cally change to reflect th e presence of a 14.318 mhz crystal. table c-6. CX25870/871 register values for autoconfiguration modes 27?30 (2 of 2) autoconfiguration mode # 27 28 (5) 29 (5) 30
appendix c autoconfiguration mode register values and details CX25870/871 flicker-free video encoder with ultrascale technology c-14 conexant 100381b table c-7. CX25870/871 register values for autoconfiguration modes 31?36 (1 of 2) autoconfiguration mode # 31 32 33 34 35 36 auto-config register (index 0xb8) hexadecimal value: reserved 40 41 42 43 44 purpose of mode: desktop de sktop desktop desktop desktop type of digital input: rgb rgb rgb rgb ycrcb active resolution: 640x480 640x480 800x600 800x600 640x480 overscan ratio: higher hi gher higher higher higher horizontal overscan ratio/percentage (hoc): 18.34 20.27 19.26 19.03 18.34 vertical overscan ratio/percentage (voc): 19.34 19.79 19.34 18.40 19.34 overscan percentages delta (hoc - voc): ?1.00 0.48 ?0.08 0.63 ?1.00 h_clki = htotal 770 950 1170 950 770 vlines_i = vtotal 645 650 805 800 645 h_blanki = horizontal blanking region 113 271 323 131 113 v_blanki = vertical blanking region 100 104 125 122 100 type of video output: ntsc p al-bdghi ntsc pal-bdghi ntsc frequency of clk (hz) 29769241 30875015 56454552 37999992 29769241 type of clock: pixel only pixel only pixel only pixel only pixel only register address register value register value register value register value register value 0x38 00 00 20 00 00 0x76 64 b8 58 80 64 0x78 80 80 20 20 80 0x7a 8c 92 b0 b2 8c 0x7c 9e ac c8 d4 9e 0x7e 6e 72 ac aa 6e 0x80 b5 f3 2d 57 b5 0x82 2a 33 2a 31 2a 0x84 c5 e9 c5 ec c5 0x86 27 27 39 39 27 0x88 00 00 00 00 00 0x8a 02 b6 92 b6 02 0x8c 71 0f 43 83 71
CX25870/871 appendix c autoconfiguration mode register values and details flicker-free video encoder with ultrascale technology 100381b conexant c-15 0x8e 03 0b 0c 03 03 0x90 85 8a 25 20 85 0x92 64 68 7d 7a 64 0x94 e0 e0 58 58 e0 0x96 36 36 3b 3b 36 0x98 50 48 11 f6 50 0x9a 57 51 a1 98 57 0x9c 14 e4 46 8e 14 0x9e 3b b8 17 e3 3b 0xa0 0d 0d 19 10 0d 0xa2 0a 24 0a 24 0a 0xa4 e5 f0 e5 f0 e5 0xa6 75 58 74 57 75 0xa8 79 81 77 7f 79 0xaa 44 48 43 48 44 0xac 85 8c 85 8c 85 0xae f2 3d 21 e1 f2 0xb0 40 e7 0b 5b 40 0xb2 c8 c2 59 de c8 0xb4 1e 24 18 1d 1e note(s): 1. rgb digital input denotes that the CX25870/871 will be configured to receiv e the rgb default pixel input mode after an autoconfiguration command, which is 24-bi t, rgb-multiplexed (i.e., in_mode[3:0] = 0000). if the desired rgb pixel input mode is not 24-bit rgb multiplexed, th e CX25870/871's in_mode[3:0] bits must be programmed to the desired rgb pixel input mode immediately before initia ting a write to the config[5:0] bits. 2. ycrcb digital input' denotes that the cx 25870/871 will be configured to receive ycrcb pixel data after an autoconfiguration command. the CX25870/871's in_m ode[3:0] bits must be programmed to the desired ycrcb pixel i nput mode immediately before initiating a write to the config[5:0] bits. 3. CX25870/871 registers not listed in this table (including in_mode[3:0]) do not get reprogrammed as a result of an autoconfiguration command. 4. pixel or character signifies that this overscan ratio is acce ptable for 8-clock per character graphics controllers or pixel-c lock controllers. 5. the CX25870/871 will be in master interf ace immediatel y after any autoconfiguration m ode except mode 28 and mode 29. 6. mode 44 would ideally have 858 clocks pe r line. however, since 858 is not a multiple of 8, then 880 clocks per line was utilized instead. 7. these autoconfiguration valu es assume a 13.500 mhz crysta l resides between the xtalin and xtalout pins. if the 14318_xtal bit is set, then these autoconfigur ation values will automati cally change to reflect th e presence of a 14.318 mhz crystal. table c-7. CX25870/871 register values for autoconfiguration modes 31?36 (2 of 2) autoconfiguration mode # 31 32 33 34 35 36
appendix c autoconfiguration mode register values and details CX25870/871 flicker-free video encoder with ultrascale technology c-16 conexant 100381b table c-8. CX25870/871 register values for autoconfiguration modes 37?42 (1 of 2) autoconfiguration mode # 37 38 39 40 41 42 auto-config register (index 0xb8) hexadecimal value: 45 46 47 50 51 52 purpose of mode: desktop desk top desktop desktop game desktop type of digital input: ycrcb ycrcb ycrcb rgb rgb rgb active resolution: 640x480 800x600 800x600 800x600 320x200, pix_double set 1024x768 overscan ratio: higher higher h igher standard standard higher horizontal overscan ratio/percentage (hoc): 20.27 19.26 19.03 15.59 21.86 18.04 vertical overscan ratio/percentage (voc): 19.79 19.34 18.40 15.64 30.90 18.11 overscan percentages delta (hoc - voc): 0.48 ?0.08 0.63 ?0.05 ?9.04 ?0.07 h_clki = htotal 950 1170 950 1170 2000 1170 vlines_i = vtotal 650 805 800 770 315 1015 h_blanki = horizontal blanking region 271 323 131 323 453 127 v_blanki = vertical blanking region 104 125 122 105 65 150 type of video output: pal-bdghi ntsc pal-bdghi ntsc pal-bdghi ntsc frequency of clk (hz) 30875015 56454552 37999992 54000000 31500000 71181793 type of clock: pixel only pixel on ly pixel only pixel only pixel or character pixel only register address register value register value register value register value register value register value 0x38 00 20 00 20 40 20 0x76 b8 58 80 f0 e0 c8 0x78 80 20 20 20 80 00 0x7a 92 b0 b2 aa 94 e0 0x7c ac c8 d4 be b0 fc 0x7e 72 ac aa 9e 78 fa 0x80 f3 2d 57 f3 09 ab 0x82 33 2a 31 25 42 28 0x84 e9 c5 ec ce ca c8 0x86 27 39 39 38 27 4b 0x88 00 00 00 00 00 00 0x8a b6 92 b6 92 d0 92
CX25870/871 appendix c autoconfiguration mode register values and details flicker-free video encoder with ultrascale technology 100381b conexant c-17 0x8c 0f 43 83 43 c5 7f 0x8e 0b 0c 03 0c 1f 04 0x90 8a 25 20 02 3b f7 0x92 68 7d 7a 69 41 96 0x94 e0 58 58 58 c8 00 0x96 36 3b 3b 3b 31 3f 0x98 48 11 f6 ef 21 de 0x9a 51 a1 98 5e 80 ad 0x9c e4 46 8e 00 00 e8 0x9e b8 17 e3 00 00 a2 0xa0 0d 19 10 18 0e 1f 0xa2 24 0a 24 0a 24 0a 0xa4 f0 e5 f0 e5 f0 e5 0xa6 58 74 57 74 58 74 0xa8 81 77 7f 78 81 77 0xaa 48 43 48 43 48 43 0xac 8c 85 8c 85 8c 85 0xae 3d 21 e1 17 d3 c2 0xb0 e7 0b 5b 5d 2d 72 0xb2 c2 59 de 74 08 4f 0xb4 24 18 1d 19 24 13 note(s): 1. rgb digital input denotes that the CX25870/871 will be configured to receiv e the rgb default pixel input mode after an autoconfiguration command, which is 24-bi t, rgb-multiplexed (i.e., in_mode[3:0] = 0000). if the desired rgb pixel input mode is not 24-bit rgb multip lexed, the CX25870/871's in_mod e[3:0] bits must be progra mmed to the desired rgb pixel input mode immediately before initia ting a write to the config[5:0] bits. 2. ycrcb digital input denotes th at the CX25870/871 will be confi gured to receive ycrc b pixel data after an autoconfiguration command. the CX25870/871's in_mod e[3:0] bits must be programmed to the de sired ycrcb pixel input mode immediately before initiating a write to the config[5:0] bits. 3. CX25870/871 registers not listed in this table (including in_mode[3:0]) do not get reprogrammed as a result of an autoconfiguration command. 4. pixel or character signifies that this overscan ratio is acce ptable for 8-clock per character graphics controllers or pixel-c lock controllers. 5. the CX25870/871 will be in master interf ace immediatel y after any autoconfiguration m ode except mode 28 and mode 29. 6. mode 44 would ideally have 858 clocks pe r line. however, since 858 is not a multiple of 8, then 880 clocks per line was utilized instead. 7. these autoconfiguration valu es assume a 13.500 mhz crysta l resides between the xtalin and xtalout pins. if the 14318_xtal bit is set, then these autoconfi guration values will automati cally change to reflect the presence of a 14.318 mhz crystal. table c-8. CX25870/871 register values for autoconfiguration modes 37?42 (2 of 2) autoconfiguration mode # 37 38 39 40 41 42
appendix c autoconfiguration mode register values and details CX25870/871 flicker-free video encoder with ultrascale technology c-18 conexant 100381b table c-9. CX25870/871 register values for autoconfiguration modes 43?47 (1 of 2) autoconfiguration mode # 43 44 45 46 47 auto-config register (index 0xb8) hexadecimal value: 53 54 55 56 57 purpose of mode: des ktop dvd/noninterlaced input game desktop for brazil desktop for argentina type of digital input: rgb rgb rgb rgb rgb active resolution: 1024x768 720x480 320x200, pixel_double set 640x480 640x480 overscan ratio: higher very low (dvd playback) standard sta ndard standard horizontal overscan ratio/percentage (hoc): 16.20 1.24 20.20 13.79 16.56 vertical overscan ratio/percentage (voc): 16.67 1.23 21.40 13.58 16.67 overscan percentages delta (hoc - voc): ?0.47 0.01 ?1.20 0.21 ?0.11 h_clki = htotal 1410 880 1848 784 944 vlines_i = vtotal 1000 525 275 600 625 h_blanki = horizontal blanking region 337 140 429 126 266 v_blanki = vertical blanking region 147 36 43 75 90 type of video output: pal-bdghi ntsc ntsc pal-m (brazil) pal-nc (argentina) frequency of clk (hz) 70499989 27692310 30461552 28195793 29500008 type of clock: pixel only pixel or character pixel or character pixel only pixel only register address register value register value register value register value register value 0x38 24 00 40 00 00 0x76 c0 e0 90 00 60 0x78 00 d0 80 80 80 0x7a dc 82 90 84 8a 0x7c 08 92 a2 a4 a6 0x7e f0 5c 72 6a 70 0x80 bf 1b cd 7d c1 0x82 2f 13 2b 22 2e 0x84 f1 f2 c2 d4 f2 0x86 4b 26 27 27 27 0x88 00 00 00 00 00
CX25870/871 appendix c autoconfiguration mode register values and details flicker-free video encoder with ultrascale technology 100381b conexant c-19 0x8a 82 70 38 10 b0 0x8c 51 8c ad 7e 0a 0x8e 0d 03 1f 03 0b 0x90 e8 0d 13 58 71 0x92 93 24 2b 4b 5a 0x94 00 e0 c8 e0 e0 0x96 3f 36 31 36 36 0x98 33 00 c3 92 00 0x9a a3 50 40 54 50 0x9c 55 c5 d9 0e 72 0x9e 55 4e 89 88 1c 0xa0 1f 0c 0d 0c 0d 0xa2 24 0a 0a 2a 24 0xa4 f0 e5 e5 f0 f0 0xa6 56 76 75 57 57 0xa8 7e 79 78 80 80 0xaa 47 44 44 48 48 0xac 8c 85 85 8c 8c 0xae 9b d1 33 6e 1e 0xb0 29 45 28 db c0 0xb2 26 17 15 76 15 0xb4 18 21 1e 20 1f note(s): 1. rgb digital input denotes that the CX25870/871 will be configured to receiv e the rgb default pixel input mode after an autoconfiguration command, which is 24-bi t, rgb-multiplexed (i.e., in_mode[3:0] = 0000). if the desired rgb pixel input mode is not 24-bit rgb multiplexed, th e CX25870/871?s in_mode[3:0] bits must be programmed to the desired rgb pixel input mode immediately before initia ting a write to the config[5:0] bits. 2. ycrcb digital input denotes th at the CX25870/871 will be confi gured to receive ycrc b pixel data after an autoconfiguration command. the CX25870/871's in_mod e[3:0] bits must be programmed to the de sired ycrcb pixel input mode immediately before initiating a write to the config[5:0] bits. 3. CX25870/871 registers not listed in this table (including in_mode[3:0]) do not get reprogrammed as a result of an autoconfiguration command. 4. pixel or character signifies that this overscan ratio is acce ptable for 8-clock per character graphics controllers or pixel-c lock controllers. 5. the CX25870/871 will be in master interf ace immediatel y after any autoconfiguration m ode except mode 28 and mode 29. 6. mode 44 would ideally have 858 clocks pe r line. however, since 858 is not a multiple of 8, then 880 clocks per line was utilized instead. 7. these autoconfiguration valu es assume a 13.500 mhz crysta l resides between the xtalin and xtalout pins. if the 14318_xtal bit is set, then these autoconfi guration values will au tomatically change to reflect the presence of a 14.318 mhz crystal. table c-9. CX25870/871 register values for autoconfiguration modes 43?47 (2 of 2) autoconfiguration mode # 43 44 45 46 47
appendix c autoconfiguration mode register values and details CX25870/871 flicker-free video encoder with ultrascale technology c-20 conexant 100381b
100381b conexant d-1 d appendix d closed caption pseudo code /* filename: cc_870_function.c */ //causes cx870/871 encoder to encode 2 bytes of data on every odd field=field 1 #include stdio.h #include conio.h <#include other necessary header files> char ccdatabyte1, ccdatabyte2; // define global vari- ables //any graphics controller/mpeg2 decoder is assumed to be the i2c master for this design //controller/data master sends the cx870/871 the digital cc bytes necessary for encoding into the composite video signal or luma signal for s-video output //h_clko[11:0] value should exist in hex format. this register equals bits3-0 //of register 0x86 and bits 7-0 of register 0x76 870_ccencoding_onfield1(int ccdatabyte1, int ccdatabyte2, int h_clko) { int cbits, cc_pipe1, cc_add_hex, ccr_start_hex, ccsel, readbit; int readbitarray[8] = {0}; //initializes all element of readbitarray to 0 float cc_add; float ccr_start; cbits = 17; cc_pipe1=60; ccsel = 4; //ccsel[3:0] = 0100 so cc data is encoded on line 21 //for 525-line systems and line 23 for 625-line systems //initialization section write eccgate to 1; //this is bit 3 of register c4 for the cx870/871 //no further closed caption encoding
appendix d closed caption pseudo code CX25870/871 flicker-free video encoder with ultrascale technology d-2 conexant 100381b will be performed //until ccf1b1 & ccf1b2 registers are again written; //null will be transmitted on appropriate cc line in this case write eccf1 to 1; //this is bit 4 of register c4 for the cx870/871 //enables cc encoding on field 1 write eccf2 to 0; //this is bit 5 of register c4 for the cx870/871 //disables cc encoding for field 2 if (625line == 0) //?625line? = bit 2 of register 0xa2 { // 525-line format=ntsc is being transmitted //by cx870/871. this assumes pal-m = another //525 line format is not allowed [equation] cc_add = ($pow(2, cbits+5)/1716)*1716.0/h_clko; //equation to determine cc_add register for ntsc cc_add_hex = dec_to_hex_conversion(float cc_add); //assumes dec_to_hex_conversion fxn //this should already exist //some- where in customer?s code write cc_add( cc_add_hex); //cc_add[11:0] register is //comprised of bits[3:0] of //register 0xd4 and bits[7:0] of //cx870/871 reg- ister 0xd2 [equation] ccr_start = h_clko*10.003*27/1716 + cc_pipe1; //eqn to determine ccr_start register for ntsc ccr_start_hex = dec_to_hex_conversion(float ccr_start); //assumes dec_to_hex_conversion
CX25870/871 appendix d closed caption pseudo code flicker-free video encoder with ultrascale technology 100381b conexant d-3 fxn //this should already exist //some- where in customer?s code write ccr_start(ccr_start_hex); //ccr_start[8:0] reg- ister is //comprised of bit[4] of regis- ter //0xd4 and bits[7:0] of cx870/871 //register 0xd0 } else { // 625-line format = pal is being transmitted by cx870/871 //this assumes pal-m with its? 525 line format is not allowed [equation] cc_add = ($pow(2, cbits+5)/1716)*1728.0/h_clko; //eqn to determine cc_add register for pal cc_add_hex = dec_to_hex_conversion(float cc_add); //assumes dec_to_hex_conversion fxn //this should already exist //some- where in customer?s code write cc_add( cc_add_hex); //cc_add[11:0] register is //comprised of bits[3:0] of //register 0xd4 and bits[7:0] of //cx870/871 reg- ister 0xd2 [equation] ccr_start = h_clko*10.003*27/1728 + cc_pipe1; //eqn to determine ccr_start reg- ister for pal ccr_start_hex = dec_to_hex_conversion(float ccr_start); //assumes dec_to_hex_conversion fxn //already exists somewhere in //cus- tomer?s code
appendix d closed caption pseudo code CX25870/871 flicker-free video encoder with ultrascale technology d-4 conexant 100381b write ccr_start(ccr_start_hex); //ccr_start[8:0] reg- ister is //comprised of bit[4] of regis- ter //0xd4 and bits[7:0] of cx870/871 //register 0xd0 } //previous initialization code only needs to be performed once by i2c master //closed caption encoding operation readbitarray[] = cx870readbackfxn(estatus = 01); //ccstat_o will be readbitarray[3] after this function executes or readbit = readccstat_o() ; //cx870/871 has full readback ability of all bits. //no longer is it necessary to use legacy bt869 method of reading //back status bits if (readbitarray[3] == 0) //alternative if statement could be ?if (readbit == 0)? { //closed caption bytes for field 1 = odd field have already been //encoded and ccstat_o has been cleared write ccf1b1( ccdatabyte1); //assumes ccdatabyte1 is in hex format //already. encode new cc data. write ccf1b2( ccdatabyte2); //assumes ccdatabyte2 is in hex format //already. encode new cc data. //data is not latched until second of the 2 byte data sequence is written //this prevents writing of partial data sequence //for this reason, data must be written in order of byte 1 and then byte 2 //ccstat_o will be automatically be set by the cx870/871 until cc bytes for odd //field = field 1 have been encoded } else
CX25870/871 appendix d closed caption pseudo code flicker-free video encoder with ultrascale technology 100381b conexant d-5 //ccstat_o = 1 because cc data has already been written for field 1=odd field //& has not yet been encoded onto analog video output signal for the odd field //ccstat_o will be reset immediately after the clock run-in online 284 for ntsc //and line 335 for pal return 0; //ccstat_0 = 1 so cc bytes were not encoded on this pass //through the 869_ccencoding_onfield1 procedure return 0; } //**************************************************** bt869readbackfxn(int estatus) //unlike the previous conexant vga encoder, the cx870/871 does have //registers than can be directly read-back. as a result this //bt869readbackfxn should only be used if the software engineer seeks to use //the legacy method of read- back found in the bt868/869. { int readmonstat_ccarray[8] = {0}; //entire array now holds 0 write estatus; //estatus[1:0]= {bits 7(msb) and 6 of register 0xc4} // estatus[1:0]= 01 from function call. // 00 and 10 possible for estatus as well // yielding different readback information graphics controller issues 0x89 or 0x8b for the cx870/871's device address; //no subaddress required here since the cx870/871 //only has 1 read register to check with the legacy method //this step has the effect of reading a single byte //of data from the cx870/871 //table 2-2 readback bit map says that monstat_a,b,c //bits = bits 7-5 //while bit 4 = ccstat_e, bit 3 = ccstat_o, // bits 2-0 = field[2:0] // this ensures the least significant bit of the device write portion of //the transaction is '1' which indicates to the encoder that it must //send a byte of data on the next i2c transaction. do not write a //subaddress to the cx870/871(this is not necessary since the cx870/871 //only appears to have 1 read register with the legacy method) and then //read the "next" byte after the ack. controller_transmits_i2c_stop; //i2c master must issue an i2c stop to
appendix d closed caption pseudo code CX25870/871 flicker-free video encoder with ultrascale technology d-6 conexant 100381b //finish the read transac- tion. an ack is //not nec- essary before closing the //transaction because the cx870/871 just //ignores the ack anyways return(readmonstat_ccarray[]); }
100381b conexant e-1 e appendix e hdtv output mode note(s): warning: conexant is pursuing multiple pate nts surrounding this function e.1 introduction a high definition television system can display images that are better than existing standard definition tv formats such as ntsc, pal, and secam. hdtv pictures are more true-to-life becau se the resolution of the tv image is much higher, and the colo rs are more accurate. many hdtvs are being equipped with a hd input port that accepts analog component yp b p r or analog rgb or both. recognizing this fact, conexant has in cluded an hdtv ou tput mode within the CX25870/871 which genera tes the analog component yp b p r or analog rgb outputs necessary for driving an hdtv?s hd input port(s). while in hdtv mode, the device will output either analog rgb or analog yp b p r signals and automatically insert tr ilevel synchronization pulses (when necessary) and vertical synchronizing broad pulses. the output waveforms and requirements related to the input timing and data on the input side of the CX25870/871 are explained in this section and in the various smpte standards governing the hdtv resolutions as listed in table e-5 .
appendix e hdtv output mode CX25870/871 e.2 allowable interfaces for hdtv output mode flicker-free video encoder with ultrascale technology e-2 conexant 100381b e.2 allowable interfac es for hdtv output mode the interface that the cx2587 0/871 must use in hd outp ut mode is either type of video timing slave interface. in th is configuration, the hsync* and vsync* signals must be received as inputs while the blank* signal?s usage is optional. the encoder cannot transmit the timing signal s that initiate the start of a line or the start of a frame in this mode at a ll. the CX25870/871 can provide a reference clock output?clko, or not transmit it, as needed. the en_out bit will control whether or not a clko signal is active. the blank* signal will not be re quired for the hdtv output mode interface if the graphics controller ou tputs the digital codes for the analog blanking level. for analog rgb componen t video outputs, the digital code for blanking is 00 hex for digital r, g, and b. for offset analog rgb component video outputs, the digital code for blanking is 10 hex for the digital r, g, and b pixel inputs. finally, for analog component yp b p r video outputs, the digital code for blanking is 10 hex for digital y and 80 hex for digital pr and pb. if the graphics controller does not possess the ability to output specific digital codes, then a blank* signal is a necessary part of this interface.
CX25870/871 appendix e hdtv output mode flicker-free video encoder with ultrascale technology e.2 allowable interfaces for hdtv output mode 100381b conexant e-3 the allowable interfaces for hdtv output mode are illustrated in figures e-1 and e-2 . figure e-1. CX25870/871?s pseudo-master interface with a graphics controller as the timing master graphics controller digital rgb or yprpb clock clock CX25870/ cx25871 r or p r g or y b or p b delay hsync* vsync* blank* (optional) 100381_030a figure e-2. CX25870/871?s slave interface with a graphics controller as the timing master graphics controller digital rgb or yprpb clock CX25870/ cx25871 hsync* vsync* blank* optional) 100381_031 r or p r g or y b or p b
appendix e hdtv output mode CX25870/871 e.3 interface bit functionalit y in hdtv output mode: flicker-free video encoder with ultrascale technology e-4 conexant 100381b e.3 interface bit functionality in hdtv output mode: when the CX25870 is transmitting high-d efinition outputs, several interface bits behave differently than their opera tion while broadcasting standard-definition television. these bits and their techni cal functionality are summarized in the following list: the blank* pin must be an input regardless of the slave or pseudo-master interface. if the blan k function is not enabled with the blank* pin, then the blank* pin (#38) should be tied high permanently. the en_blanko bit has no effect because the blank* signal must be an input. the same rule holds for vga(r/g/b) ? dac output operation. the en_dot bit has no effect. this bi t is related to the standard flicker filter. the fld_mode[1:0] bit field has no effect. for 1080i or any other hd-related interlaced input, vsync*'s leading edge must be received within 5 clock cycles of the middle of the total line length. for 1080i, this means the vsync* leading edge must be received on any clock period between the (2200 / 2) 5 clocks = 1095th and 1106 th clock pulse. the polarity reversing bits (hsynci, vsynci, and blanki) perform the same operations as they do with standard definition outputs.
CX25870/871 appendix e hdtv output mode flicker-free video encoder with ultrascale technology e.4 interface timing between the hdtv source device (master) 100381b conexant e-5 e.4 interface timing between the hdtv source device (master) and CX25870/ cx25871(timing slave) while in hdtv output mode, the CX25870/871 encoder should receive interface signals from the mpeg2 decoder or display processor. the interface signals that should be shared between the two devices are the hsync*, vsync*, blank*, clki, and pixel data lines (p[23: 0]). the blank* signal is optional. this signal is only necessar y if the data master cannot transmit the digital codes representing the blank leve ls to the CX25870/871. to reiterate, the codes for the digital blanking levels of th e r, g, b inputs are equal to 00 hex. the digital codes for blanking change to 10 hex for the r, g, and b pixel inputs if conversion to offset analog rgb component video outputs is desired. finally, the values for digital y must be 10 hex and for pr and pb, digital samples have to equal 80 hex for the blank period for component video out (ypbpr). clko will only be necessary if pseudo-master is used as the chosen interface. to switch the CX25870/871 encoder into hdtv output mode, the serial master must program both the out_mode [1:0] bits to 11(dac mode) and set the hdtv_en bit to 1(bit 7 of the hdtv register). immediately after these and all other steps listed in table e-1 and table e-2 , the encoder will be set up to properly generate a set of hdtv outputs so long as the synchronization, clock, and data signals are transmitted in accord ance with the timing diagrams found at the back of appendix e by the master device.
appendix e hdtv output mode CX25870/871 e.4 interface timing between the hdtv source device (master) and CX25870/ cx25871(timing slave) flicker-free video e-6 conexant 100381b table e-1. CX25870 register settings for alternate 24-bit rgb multiplexed in?hdtv yp b p r out and hdtv rgb out atsc resolution CX25870 register address 1080i 720p 480p explanation 0xd6 0c 0c 0c out_mode [1:0] field set to 11=dac mode to turn on hdtv outputs. video[0-3] is hdtv output mode . hdtv_en bit must be set as well. video[0] = hd r or pr, video[1] = hd g or y, video[2] = hd b or pb 0x2e c3 c2 c5 hdtv_en set. rgb2yprpb set. raster_sel [1:0] field adjusted for each atsc resolution. hd_sync_edge set for 480p resolution only. for rgb out, rgb2yprpb bit must be 0 so th is register will be 83 / 82 / and 85. for eia770.3 compliance, disable the trilevel sync on both the p r and p b outputs by setting the rpr_sync_dis(bit 5) an d bpb_sync_dis(bit 3) bits. 0x32 01 01 00 setup_hold_adj bit is bit 4. csc_sel bit set for hi-frequ ency atsc resolutions only. 0x3c 80 80 80 mcompy stays the same for 480p/720p/1080i in, y/pr/pb out. or rgb out. 0x3e 45 45 48 mcompu must be changed for 480p and 720p/1080i in, y/pr/pb out. mcompu must be changed to 80hex for 480p/720p/1080i in, rgb out. 0x40 51 51 5b mcompv must be changed for 480p and 720p/1080i in, y/pr/pb out. mcompv must be changed to 80hex for 480p/720p/1080i in, rgb out. 0xc4 01 01 01 state of en_out varies according to interf ace used with master devi ce. hex value of 01 for this register corresponds to pseu do-master without a blank* interface. 0xc6 80 80 80 state of en_blanko & en_dot varies according to interface used with master device. hex value of 80 for this register corresponds to pseudo-master without a blank* interface. in_mode[2:0] = 000 - defines input format as 24-bit rgb multiplexed. 0xce 24 24 24 adjust this register as necessary to route y/pr/pb out from the CX25870's 4 dacs out_muxd[1:0]= 00 =video[0] = pr = r {disabled from dacdisd=1} out_muxc[1:0]= 10 =video[2] = pb = b out_muxb[1:0]= 01 =video[1] = y = g out_muxa[1:0]= 00 =video[0] = pr = r 0xa0 21 21* 8c pll_int[5:0] = 21 for 720p @ 74.25 mhz *pll_int[5:0] = 20 for 720p @ 74.16 mhz 0x9e 00 00** 00 pll_fract[15:8] = 00 for 720p @ 74.25 mhz **pll_fract[15:8] = f5 for 720p @ 74.16 mhz 0x9c 00 00** 00 pll_fract[7:0] = 00 for 720p @ 74.25 mhz **pll_fract[7:0] = c3 for 720p @ 74.16 mhz 0xba 28 28 28 slaver set. interface is slave timing (pseudo-master or slave) hsync*/vsync* sent to CX25870. dacd disabled. pr/y/pb tran smitted from daca/dacb/dacc wait state = 75 ms. yes yes yes ready encoder for timing reset oper ation. 75 ms = many factors of safety. 0x6c c6 c6 c6 set timing_reset bit. cleared automatically. (*) = if graphics controller is character b ased with 8 pixel clocks/character, pll_int sh ould be modified to generate a 74.1600 0 mhz. clko and clki frequency. (**) = if graphics controller is character b ased with 8 pixel clocks/character, pll_fr act should be modified to generate a 74.1 6000 mhz. clko and clki frequency.
CX25870/871 appendix e hdtv output mode flicker-free video encoder with ultrascale technology e.4 interface timing between the hdtv source device (master) 100381b conexant e-7 table e-2. CX25870 register settings for 24-bit yprpb multiplexed in?hdtv yp b p r out atsc resolution CX25870 register address 1080i 720p 480p explanation 0xd6 0c 0c 0c out_mode [1:0] field set to 11=dac mode to turn on hdtv outputs. video[0-3] is hdtv output mode . hdtv_en bit must be set as well. video[0] = hd pr, video[1] = hd y, video[2] = hd pb 0x2e ab*** aa*** ad*** hdtv_en set. rgb2yprpb off. raster _sel[1:0] field adjusted for each atsc resolution. hd_sync_edge set for 480p resolution only. for eia770.3 compliance, the tril evel sync has been di sabled on both the pr and pb outputs by setting the rpr_sync_dis(bit 5) and bpb_sync_dis(bit 3) bits. 0x32 09 09 08 drvs[1:0] = 00 fo r 3.3v interfacing. should be adjusted to nonzero value for low voltage interface. in_mode[3] = 1 = input format is alternate 24bit yp r p b multiplexed setup_hold_adj bit is bit 4. csc_sel bit set for hi-frequ ency atsc resolutions only. 0x3c 80 80 80 mcompy stays the same for 480p/720p/1080i in, y/pr/pb out. 0x3e 80 80 80 mcompu stays the same for 480p/720p/1080i in, y/pr/pb out. 0x40 80 80 80 mcompv stays the same for 480p/720p/1080i in, y/pr/pb out. 0xc4 01 01 01 state of en_out varies according to interface us ed with master device. h ex value of 01 for this register corresponds to pseudo-m aster without a blank* interface. 0xc6 84 84 84 state of en_blanko & en_dot varies according to interface used with master device. hex value of 80 for this register corr esponds to pseudo-master without a blank* interface. in_mode[2:0] = [1]100 - input format is alternate 24bit yp r p b multiplexed 0xce 24 24 24 adjust this register as necessary to route y pr pb out from the CX25870's 4 dacs out_muxd[1:0]= 00 =video[0] = pr {disabled from dacdisd=1} out_muxc[1:0]= 10 =video[2] = pb out_muxb[1:0]= 01 =video[1] = y out_muxa[1:0]= 00 =video[0] = pr 0xa0 21 21* 8c pll_int[5:0] = 21 for 720p @ 74.25 mhz *pll_int[5:0] = 20 for 720p @ 74.16 mhz 0x9e 00 00** 00 pll_fract[15:8] = 00 for 720p @ 74.25 mhz **pll_fract[15:8] = f5 for 720p @ 74.16 mhz 0x9c 00 00** 00 pll_fract[7:0] = 00 for 720p @ 74.25 mhz **pll_fract[7:0] = c3 for 720p @ 74.16 mhz 0xba 28 28 28 slaver set. interface is slave timing (pseudo-master or slave) hsync* & vsync* sent to CX25870. dacd disabled. pr transmitted from daca, y tr ansmitted from dacb, an d pb transmitted from dacc wait state = 75 ms yes yes yes ready encoder for timing reset oper ation. 75 ms = many factors of safety. 0x6c c6 c6 c6 set timing_reset bit. cleared automatically. note(s): (*) = if graphics controller is character b ased with 8 pixel clocks/character, pll_int should be modified to generate a 74.1600 0 mhz clko and clki frequency. (**) = if graphics controller is character based with 8 pixel clocks/character, pll_fract should be modified to generate a 74.1 6000 mhz clko and clki frequency. (***) = conversion from yprpb digital input to hdtv rgb out not possible with CX25870/871.
appendix e hdtv output mode CX25870/871 e.4 interface timing between the hdtv source device (master) and CX25870/ cx25871(timing slave) flicker-free video e-8 conexant 100381b in the default format, the hsync* signal is active low and must always be received as an input in hdtv output mode . its function is to allow the graphics controller to tell the encoder when the start of a line occurs. check the timing diagrams that appear later in this section for proper hsync* timing. in the default format, the vsync* signal is active low and must always be received as an input in hdtv output mode . its function is to allow the graphics controller to tell the encoder when the start of a frame occurs. check the timing diagrams that appear later in this section for proper vsync* timing. by default, the clock output signal w ill be transmitted via the clko port. therefore, the CX25870/871 will be in ps eudo-master interface. to switch into slave interface, the user must reset the en_out bit to turn off clko. table e-2 summarizes the default pseudo-master hdtv interface. the timing diagrams found at the end of this appendix ( figures e-5 through e-9 ) must be replicated with actual ti ming by the mpeg2 decoder or display processor for the encoder to provide correct hdtv analog rgb or analog yp b p r component video outputs. table e-3. default state of CX25870/871 immediately after switch into hdtv output mode input signals clko state of the CX25870/871 blank* hsync* vsync* state of encoder in hdtv output mode optional h h active digital rgb?analog hd rgb or digital yp r p b ?analog hd yp b p r dac conversion optional l h active start of a new line optional l l active start of a new frame
CX25870/871 appendix e hdtv output mode flicker-free video encoder with ultrascale technology e.5 automatic trilevel sync generation 100381b conexant e-9 e.5 automatic tril evel sync generation the CX25870/871 will automatically gene rate an analog synchronization pulse with three distinct voltage levels for ev ery leading edge it receives at its hsync* input (so long as raster_sel[1:0] = 10 or 11). this trilevel pulse will be comprised of a ?300 mv lowsync level, a +300 mv highsync level, and a 0 mv blanking level offset by +350 mvdc because the CX25870/871 cannot output negative voltages. figure 3, "analog and digital timing relationships", of the smpte-274m specification, shows a very detailed diagram of the trilevel sync and start of a line in 1080i mode. figure 11 of this same smpte standard illustrates the horizontal timing and trilevel sync in more detail. for those formats which require trilevel syncs, such as 1080i and 720p, the timing for certain portions of the synchronization pulses differ slightly. for instance, the amount of time each pulse is at a voltage level of ?300 mv (lowsync) is not the same from one reso lution (atsc format) to another. for 1080i, the time for the lowsync leve l each line is 44t(44 clock periods = 44*(1/74.25 mhz)= 592.5 ns for 720p, the same interval is 40t periods long which equates to 40 * (1/74.25 mhz)= 538.7 ns. in 480p resolution, in accordance with the smpte-293m specification, the CX25870/871 outputs only bilevel analog synchronization pulses. as figure 3 "analog and digital timing relationships" of the smpte-274m and -296m standards show, the period of time for the highsync also varies when moving from 1080i mode to 720p mode. in this first case, the highsync output level will be active for 44 clock periods. for 1080i, 44 clock periods * (1/74.25 mhz) = 592.6 ns. in 720p resolution, the highsync output signal will be active for 40 clock periods per output line. for 720p, 40 cloc k periods * (1/74.25 mhz)= 538.7ns, so the highsync signal will only be active for 538.7 ns per output line. due to these discrepancies, the data master will need to program the CX25870/871?s raster_sel[1:0] bits properly so the encoder knows exactly which atsc format it is going to encode . the encoder will then take care of outputting the proper anal og voltage levels (see figures e-5 through e-9 ) for the appropriate amounts of time depending on the resolution.
appendix e hdtv output mode CX25870/871 e.5 automatic trilevel sync generation flicker-free video encoder with ultrascale technology e-10 conexant 100381b the table below summarizes the di fferent permutations of the raster_sel[1:0] bits and the resolu tions/modes supported with each option. the inserted syncs will adhere to figure 3 and the analog and digital timing relationships found in the various smpte sp ecifications. all lines of the first and second fields of an inte rlaced system will contain the trilevel syncs. this includes lines #1-5 and #564-567 of the 1080i format. line 563 is an extraordinary case and the reader should defer to the smpte 274m specification for more details on this topic. an illustration of the typical trilevel sync output from the CX25870/871is shown on the next page. note that the CX25870/871 cannot transmit negative voltages. as a result, the video output is offset by +350mv to accommodate the negative sync levels listed in the governing specifications. table e-4. CX25870/cx25871 raster_sel[1:0] bit functionality raster_sel [1] raster_sel [0] hdtv/atsc mode lowsync period (ns) highsync period (ns) 11 1080i = smpte 274m (1) 44 clock periods = 592.6 ns 44 clock periods = 592.6 ns 10 720p = smpte 296m (2) 40 clock periods = 538.7ns 40 clock periods = 538.7ns 0 1 480p = smpte 293m 63 clock periods = 2.36 s. no highsync period 0 0 trilevel sync periods dictated by hsync*&vsync* input levels lowsync period = width of vsync* input highsync period = width of hsync* input note(s): (1) the CX25870/871 can also be programmed for eia-770.3 1080i fo rmat compliance. to do so, set raster_sel[1:0] = 11 and set the bpb_sync_dis and rpr_sync_dis bits to 1 to disable the trilevel sync on the pb and pr signals. (2) the CX25870/871 can also be programmed fo r eia-770.3 720p format compliance. to do so, set raster_sel[1:0] = 10 and set the bpb_sync_dis and rpr_sync_dis bits to 1 to disable the trilevel sync on the pb and pr signals. (3) to obtain any of these sm pte specifications, visit global engineering document s at: http://global.ihs.com/
CX25870/871 appendix e hdtv output mode flicker-free video encoder with ultrascale technology e.5 automatic trilevel sync generation 100381b conexant e-11 figure e-3. 1080i and 720p trilevel sync provided by CX25870/871 44t (for 274m) 44*(1/74.25 mhz) = 592.5 ns 44t (for 274m) 44*(1/74.25 mhz) = 592.5 ns 44t 44*(1/74.25 mhz) = 592.5 ns 70t (for 296m) 70*(1/74.25 mhz) = 942.8 ns 650 mv 350 mv 50 mv 40t (for 296m) 40*(1/74.25 mhz) = 538.7 ns 40t (for 296m) 40*(1/74.25 mhz) = start of the analog line 538.7 ns 100381_032 note(s): 1. trilevel sync applies to y p b , p r output signals as well as hd rgb output signals. 2. 720p trilevel sync timing differences are listed in red.
appendix e hdtv output mode CX25870/871 e.6 allowable resolutions flicker-free video encoder with ultrascale technology e-12 conexant 100381b e.6 allowable resolutions table e-5 summarizes the most popular hd resolutions or atsc video formats supported by the CX25870/871. conceivably, any hd format with a cloc k less than or equal to 80 mhz can be displayed with the raster_sel[1:0] = 00 option. this flexibility allows the CX25870/871 to receive resolutions no t yet standardized. all hdtv output mode resolutions will generate the new wss wide screen format that provides an aspect ratio of 16:9 yielding a mo vie-theatre like viewing experience. when the encoder is in hdtv output mode, the internal fifo and flicker filter blocks are bypassed. therefore, the y/p b /p r and r/g/b video outputs do not have any flickering filtering nor any overscan compensation applied to them. for 480p, 720p, and other progressive input formats, the lack of flicker filtering causes no degradation whatsoever in the video output quality as compared to the digital input. for 1080i and other interla ced input formats, the lack of flicker filtering sets off the appearance of minor flickering in screen regions with small vertical dimensions. the lack of overscan compensation in hdtv output mode results in the outer horizontal and vertical edges of the active image to appear behi nd the bezel of the television. this annoyance can be overco me by the insertion of a solid colored border around the active image itself by the data master in the digital domain. table e-5. CX25870/cx25871 hdtv supported formats a c t i v e format (h x v ) governing standards input data format (can be muxed or nonmuxed) o u t p u t a s p e c t ratio frame rate 1920x1080 = 1080i (contains trilevel syncs) smpte-274m & eia-770.3 15, 16, or 24 bit rgb or 16 or 24 bit digital yp b p r 16 : 9 30 hz. interlaced 1280x720 = 720p (contains trilevel syncs) smpte-296m & eia-770.3 15, 16, or 24 bit rgb or 16 or 24 bit digital yp b p r 16 : 9 60 hz. noninterlaced 720x480 = 480p (does not contain trilevel syncs) smpte-293m 15, 16, or 24 bit rgb or 16 or 24 bit digital yp b p r 16 : 9 60 hz. noninterlaced
CX25870/871 appendix e hdtv output mode flicker-free video encoder with ultrascale technology e.7 720p support with character clock based data masters 100381b conexant e-13 e.7 720p support with character clock based data masters character clock based graphics controllers with 8 pixel clocks per character will experience difficulty supporting the 720p atsc resolution. the reason for this is because the total line length (i.e., samples per total line = s/tl) of 1650 pixels for 720p is not evenly divisible by 8. thus, each line is comprised of an amount of characters that contains a non-zero fraction (206 + ? of a character or 206.25 total characters). to get around this shortcoming, the graphics controller must set its total line length to 1648 (htotal) pixels and change the pixel clock frequency to 74.1600 mhz. instead of the values of 1650 pixels and 74.2500 mhz. respectively as specified in the smpte-296m standard that governs the 720p resolution. all of the analog timing will then fall within th e guidelines listed in the smpte-296m specification and the CX25870 will generate the desired analog representation of the 720p atsc resolution. internal analysis of different po rtions of the 720p r/g/b and y/p b /p r waveforms has revealed that this approach is valid. all of the analog timing falls within the tolerances of the smpte-296m standard including the length of the broad pulse. in terms of clock periods, using the 74.1600 mhz. clock yields a broad pulse length in time of 20.766 s in duration. using a 74.2500 mhz. clock yields a broad pulse of 20.741 s in duration. this tiny deviation will not cause a problem for any high definition television set. to change the pixel clock frequency the encoder transmits and expects in return, the CX25870?s pll_int and pll_fract registers must be modified. for 720p support with character clock based data masters, change the pll_int[5:0] bit field from 21 hex (for 74.25 mhz.) to 20hex for 74.1600 mhz. operation. furthermore, reduce the 2-byte wide pll_fract[15:0] from 0000 hex (for 74.25 mhz.) to f5c3 hex for 74.1600 mhz. operation. this reduction in the pll_int and pll_fract registers will ensure th e encoder transmits the modified 720p clock of 74.1600 mhz. to the data master through clko and expects to receive data at this frequency coming back (via clk i). this step must be done to render 720p via characte r clock based data masters with the CX25870. programming the data master?s htotal register to 1648 is vital as well. modifying the CX25870?s h_clki register to 1648 decimal is optional because this register will have no effe ct while the encoder is outputting hdtv. in summary, for data masters which ar e character clock based with 8 and 9 pixel clocks per character and wish to support the 720p resolution, slow down the pixel input clock frequency (clki) by 90 khz. to 74.1600 mhz and compensate by reducing htotal by 2 pixels per line to 1648 pixels.
appendix e hdtv output mode CX25870/871 e.8 automatic insertion of broad pulses flicker-free video encoder with ultrascale technology e-14 conexant 100381b e.8 automatic inser tion of broad pulses in hd televisions, a frame shall begi n with five vertical sync lines each containing a broad pulse. broad pulses are the hd equivalent to the vertical synchronizing serration and equalization pulses used with present-day analog tvs. in response to the correct timin g provided through the vsync* input which triggers the start of a new frame, the CX25870/871 will automatically insert broad pulses and trilevel syncs on the first 5 lines of the first field(#1-#5) and the first 5 lines in the second field (563-568 for 1080i format). these broad pulses will adhere to the timing and voltage amplitudes found in various smpte specifications. figure e-6 illustrates the proper interface timing between the hdtv source device (master) and CX25870/ cx25871(timi ng slave) during lines that include a broad pulse in 1080i format. figure e-8 shows the relationship between the digital input signals and hdtv output for lin es that include a broad pulse in 720p format.
CX25870/871 appendix e hdtv output mode flicker-free video encoder with ultrascale technology e.9 hdtv output mode register and bit definitions 100381b conexant e-15 e.9 hdtv output m ode register and bit definitions table e-6. register bitmap for hdtv-specific registers 8-bit address d7 d6 d5 d4 d3 d2 d1 d0 2e hdtv_en* rgb2yprpb* rpr_sync _dis* gy_sync_ dis* bpb_sync_ dis* hd_sync_ edge* raster_sel[1:0]* 32 auto_chk drvs[1:0] setup_ hold_adj in_mode[3] datdly_re offset_rg b* csc_ sel* note(s): * = hdtv-specific bits table e-7. CX25870/871 registers 0x2e & 0x32?hdtv output mode bit descriptions (1 of 2) bit/register names bit/register definition hdtv_en enable hdtv output mode. out_mode[1:0] register bits must be set to 11(vga mode). 0 = enables vga mode. dacs will output analog r, g, b with standard bilevel (?40 ire) an alog syncs. (default) 1 = enables hdtv output mode. dacs will output hd tv compatible r/g/b or component video (y/pr/pb) outputs. trilevel syncs and vertica l synchronizing/broad pulses will be inserted automatically if raster_sel[1:0] = nonzero. note: en_scart bit must be 0 for hdtv output mode to be functional. rgb2yprpb hdtv output switching bit. this bit is only eff ective when hdtv_en = 1 and in_mode[3:0] = an rgb input format. 0 = digital rgb input to analog hdtv rgb output (default) 1 = digital rgb input to analog hdtv yp r p b output rpr_sync_dis 0 = enables trilevel sync on red or pr output. (default) 1 = disables trilevel sync on red or pr output. this bit will have to be set manual ly for eia-770.3 compliance. gy_sync_dis 0 = enables trilevel sync on green or y output. (default) 1 = disables trilevel sync on green or y output bpb_sync_dis 0 = enables tr ilevel sync on blue or pb output. (default) 1 = disables trilevel sync on blue or pb output. this bit will have to be set manually for eia-770.3 compliance. hd_sync_edge this bit is only effective wh en hdtv_en = 1 and raster_sel is nonzero. 0 = trilevel sync edges tran sition time is equal to 4 input clocks. (default) 1 = trilevel sync edges transition time is equal to 2 input clocks. raster_sel[1:0] this bit is only effective when hdtv_en = 1. 00 = device does not generate trilevel sync automatically in hdtv output mode. trilevel sync periods dictated by active hsync* input signal ( as highsync) and active vsync* input signal (as lowsync). (default) 01 = bilevel sync generation for 480p format 10 = trilevel sync generation for 720p format 11 = trilevel sync generation for 1080i format
appendix e hdtv output mode CX25870/871 e.9 hdtv output mode regi ster and bit definitions flicker-free video encoder with ultrascale technology e-16 conexant 100381b offset_rgb 0 = standard rgb graphic digital input. range is 0?255 decimal (default) 1 = hdtv offset rgb graphic digital input. range is 16?235 decimal. csc_sel 0 = standard color space conv ersion for rgb to y (r-y) (b-y) based on y = 0.299r + 0.587g + 0.114b (default) 1 = hdtv color space conversion fo r rgb to y (r-y) (b-y) based on y = 0.2126r + 0.7152g + 0.0722b table e-7. CX25870/871 registers 0x2e & 0x32?hdtv output mode bit descriptions (2 of 2)
CX25870/871 appendix e hdtv output mode flicker-free video encoder with ultrascale technology e.10 color space conversion functionality to support analog rgb 100381b conexant e-17 e.10 color space conv ersion functionality to support analog rgb or yp b p r component video outputs the CX25870/871 has the ability to recei ve a digital rgb stream prevalent in graphics controllers or chipsets with inte grated graphics with a width of 15/16/or 24-bits per pixel and transform it to a set of hdtv-compatible analog yp b p r component video outputs. the option of not converting the digital rgb stream to analog yp b p r is available as well. in this case, the CX25870/871 would output a set of hdtv-compatible analog rgb component video outputs based on the same 15/16/or 24-bits per pixel rgb digital input. the CX25870/871 can support the conversion from the hdtv color-difference digital yp b p r color space directly to analog yp b p r component video outputs seamlessly. no color space conversion nor register reprogramming is necessary for this case. however, the hdtv color-difference digital yp b p r color space is slightly different from the standard digital 4:2: 2 ycrcb (i.e., ccir601) stream found within consumer applica tions such as set-top boxes. as a result, the CX25870/871 must be reprogrammed to new register values not found in table e-1 to accommodate for th e differences in the two formats. for this complete register set, contact your local conexant field applications engineer. once obtained, program up the CX25870 as specified and it will provide analog yp b p r video outputs based on standard 4:2:2 ycrcb mpeg2 input data. the resulting outputs will be of high quality and viewable on smpte274m and smpte 296m standard hdtvs. for design simplicity, conexant recommend s the data master just send digital yp r p b for consumer applicatio ns instead of ycrcb. for reference these matrix equations for conversion into digital pb and digital pr are listed below: pb = {0.5 / (1 ? 0.0722)} (b? ? y?) where (b? ? y?) = cb pr = {0.5 / (1 ? 0.2126)} (r? ? y?) where (r? ? y?) = cr note(s): 1. the CX25870/871?s mcompu regi ster must contain a value of 45 hex prior to performing a color space conversion from digital rgb to analog ypbpr. the cx 25870/871?s mcompv register must contain a value of 51 hex prior to performing a color space conversion from digital rgb to analog ypbpr. 2. digital pb and digital pr are expressed as p?b and p?r in the smpte specifications. finally, the CX25870/871 cannot provide analog rgb video outputs from either color-difference digital yprpb or 4:2:2 ycrcb mpeg2 input data. the encoder will not perform th is color space conversion wh atsoever. for analog rgb component hd out, a digital rgb input stream must be sent by the data master.
appendix e hdtv output mode CX25870/871 e.11 recommended output filters for hdtv & sdtv flicker-free video encoder with ultrascale technology e-18 conexant 100381b e.11 recommended output filters for hdtv & sdtv according to the smpte274m standard th at governs the 1080i atsc resolution, ?the y signal for component hd video output shall have a bandwidth nominally of 30 mhz. in addition, the p r and p b signals shall have th e same bandwidth as that of the associated y signal at the an alog originating equipment.? other filter criteria found in the various smpte st andards include the amplitude limit for ripple tolerance in the passband of +/- 0.5 db relative to insertion loss at 100 khz. for group-delay, smpte states that the ?group delay in the filters (should be) sufficiently tight to produce good pe rformance while allowing the practical implementation of the filters themselves" (from smpte 274m and smpte293m(720p) standards). as result of these criteria, during high definition output mode, each CX25870 dac output requires a low pass filter with a passband from dc to 30 mhz. while adhering to the aforementioned group delay and passband ripple tolerances. unfortunately, the filtering requirements for standard definition television are quite different in several areas than filtering for hdtv. the most important difference is that standard de finition standards such as ntsc, pal, and secam require a much lower 8 mhz. passband starting at dc than hdtv. this bandwidth difference coupled with the differing voltage amplitudes of the signals themselves forced conexant to design a new low pass filter with a wider passband to accommodate the hd outputs. after extensive testing and cost/benefit trade-offs, the company r ecommends that any customer using the encoder for both its standard definition and high definition capabilities design-in the low pass filter found in figure e-4 . this filter has been shown to exhibit many of the desired roll off, ripple, and passband characteristics defined in the aforementioned smpte standards.
CX25870/871 appendix e hdtv output mode flicker-free video encoder with ultrascale technology e.11 recommended output filters for hdtv & sdtv 100381b conexant e-19 figure e-4. recommended low pass filter configuration for each CX25870 dac for generation of high definition and ntsc/pal/secam tv outputs 100381_084 CX25870/871 dac d cvbs = composite #2 vaa 3.3 v 1 2 3 1 2 3 d9 bat54s sot-23 5443r10-004 r11 75.0 ? 0805 1% sd filter hd filter hd filter hd filter c21 270 pf 0805 5% 22 pf 0805 5% c22 330 pf 0805 5% l1 1.8 h 1210 5% dac b y = luma or hd y vaa 3.3 v 1 2 3 1 2 3 d7 bat54s sot-23 5443r10-004 r2 75.0 ? 0805 1% c9 62 pf 0805 5% c8 33 pf 0805 5% c10 75 pf 0805 5% bout l1 0.27 h 1210 5% dac c c = chroma or hd pr vaa 3.3 v 1 2 3 1 2 3 d8 bat54s sot-23 5443r10-004 r7 75.0 ? 0805 1% c9 62 pf 0805 5% c8 33 pf 0805 5% c10 75 pf 0805 5% cout l1 0.27 h 1210 5% dac a cvbs = composite #1 or hd pb vaa 3.3 v 1 2 3 1 2 3 d9 bat54s sot-23 5443r10-004 r11 75.0 ? 0805 1% c9 62 pf 0805 5% c8 33 pf 0805 5% c10 75 pf 0805 5% dout l1 0.27 h 1210 5% note(s): 1. hd filter imparts a passband of dc to 30 mhz. 2. sd filter imparts a passband of dc to 8 mhz.
appendix e hdtv output mode CX25870/871 e.12 timing diagrams fo r hdtv output mode flicker-free video encoder with ultrascale technology e-20 conexant 100381b e.12 timing diagrams for hdtv output mode review the next five pages ( figures e-4 through e-8 ) for illustrations of the relationship between the digital inputs received by the CX25870/871 and the hdtv output signals transmitted by th e encoder while in hdtv output mode.
CX25870/871 appendix e hdtv output mode flicker-free video encoder with ultrascale technology e.12 timing diagrams for hdtv output mode 100381b conexant e-21 figure e-5. proper interface timing between the hdtv s ource device (master) and CX25870/871 (timing slave): active line in 1080i and 720p atsc format (raster sel[1:0] = 11 or 10) for r, g, b, and y analog outputs 100381_067 . . . . . . . . . . . . . blank period (generated by controller) 70t (for 720p) 70*(1/74.25 mhz) = 942.8 ns 44t (for 1080i) 44*(1/74.25 mhz) = 592.5 ns 44t (for 1080i) 44*(1/74.25 mhz) = 592.5 ns 40t (for 720p) 40*(1/74.25 mhz) = 538.7 ns 40t (for 720p) 40*(1/74.25 mhz) = 538.7 ns 44t 44*(1/74.25 mhz) = 592.5 ns low sync period hi-sync period sync blank period rgb conversion period (digital data sent by controller 13.468 ns. 11 clk pipeline delay 11 clk pipeline delay 11 clks pipeline delay min. 4 clks 132 clks 11 clk pipeline delay rgb1 rgb2 rgb3 rgb4 rgb5 rgb6 rgb7 rgb8 rgb9 automatically generated by CX25870 blank* has no effect when either sync* is active or in the tri-level sync period r, g, b, and y (analog outputs) 650 mv 350 mv 50 mv clki [p23?p0] hsync* (input to CX25870) 1 vsync* (input to CX25870) blank* (input to CX25870) 1050 mv *assumes 24-bit non-mux rgb digital input { not to scale
appendix e hdtv output mode CX25870/871 e.12 timing diagrams fo r hdtv output mode flicker-free video encoder with ultrascale technology e-22 conexant 100381b figure e-6. proper interface timing between the hdtv s ource device (master) and CX25870/871 (timing slave): active line in 1080i and 720p atsc format (raster sel[1:0] = 11 or 10) for p b and p r analog outputs 100381_068 { not to scale . . . . . . . . . . . . . blank period (generated by controller) 70t (for 720p) 70*(1/74.25 mhz) = 942.8 ns 44t (for 1080i) 44*(1/74.25 mhz) = 592.5 ns 44t (for 1080i) 44*(1/74.25 mhz) = 592.5 ns 40t (for 720p) 40*(1/74.25 mhz) = 538.7 ns 40t (for 720p) 40*(1/74.25 mhz) = 538.7 ns 44t 44*(1/74.25 mhz) = 592.5 ns low sync period hi-sync period sync blank period rgb conversion period (digital data sent by controller 13.468 ns. 11 clk pipeline delay 11 clk pipeline delay 11 clks pipeline delay min. 4 clks 132 clks 11 clk pipeline delay rgb1 rgb2 rgb3 rgb4 rgb5 rgb6 rgb7 rgb8 rgb9 automatically generated by CX25870 blank* has no effect when either sync* is active or in the tri-level sync period p b and p r (analog outputs) 650 mv 350 mv 50 mv 0 mv clki [p23?p0] hsync* (input to CX25870) 1 vsync* (input to CX25870) blank* (input to CX25870) 700 mv *assumes 24-bit non-mux rgb digital input with color space conversion done internally 132 clks
CX25870/871 appendix e hdtv output mode flicker-free video encoder with ultrascale technology e.12 timing diagrams for hdtv output mode 100381b conexant e-23 figure e-7. proper interface timing between the hdtv s ource device (master) and CX25870/871 (timing slave): broad pulse line in 1080i atsc format (raster sel[1:0] = 11)?odd field . . . . blank period (generated by controller) 44t (for 1080i) 44*(1/74.25 mhz) = 592.5 ns 44t (for 1080i) 44*(1/74.25 mhz) = 592.5 ns 44t 44*(1/74.25 mhz) = 592.5 ns low sync period hi-sync period blank period 11 clk pipeline delay 11 clk pipeline delay min. 4 clks (analog outputs) min. 4 clks 11 clk pipeline delay 11 clk pipeline delay automatically generated by CX25870 broad pulse period (generated by CX25870 encoder) blank* has no effect when either sync* is active or in the tri-level sync period r, g, b, and y, p b p r 650 mv 350 mv 50 mv [p23?p0] hsync* (input to CX25870) 1 vsync* (input to CX25870) blank* (input to CX25870) 700 mv note(s): a. CX25870/871 automatically generates a broad pulse levels and timing. if a blank* signal is not used, adhere to notes b. and c. b. r, g, b, and y digital samples have to equal 00 hex = 0 decimal for the blank period. c. pr and pb digital samples have to equal 80 hex = 128 decimal for the blank period. time scale compressed. 100381_069
appendix e hdtv output mode CX25870/871 e.12 timing diagrams fo r hdtv output mode flicker-free video encoder with ultrascale technology e-24 conexant 100381b figure e-8. proper interface timing between the hdtv s ource device (master) and CX25870/871 (timing slave): two successive active fields in 1080i atsc format (raster sel[1:0] = 11) note(s): a. CX25870/871 automaticall generates a broad pulse levels and timing. if a blank* signal is not used, adhere to notes b. and c. b. r, g, b, and y digital samples have to equal 00 hex = 0 decimal for the blank period. c. pr and pb digital samples have to equal 80 hex = 128 decimal for the blank period. 100381_070 . . . . . . . . blank period (generated by controller) 70t (for 720p) 70*(1/74.25 mhz) = 942.8 ns. 44t (for 1080i) 44*(1/74.25 mhz) = 592.5 ns. 44t (for 1080i) 44*(1/74.25 mhz) = 592.5 ns. 40t (for 720p) 40*(1/74.25 mhz) = 538.7 ns. 40t (for 720p) 40*(1/74.25 mhz) = 538.7 ns. 44t 44*(1/74.25 mhz) = 592.5 ns. low sync period hi-sync period blank period active period for odd field sync and blank period active period for even field 11 clk pipeline delay 11 clk pipeline delay 11 clk pipeline delay min. 4 clks 562 1/2 lines line (analog outputs) odd field begins even field begins automatically generated by CX25870 blank* has no effect when either sync* is active or in the tri-level sync period vsync* pulse must be received within +/- 5 clock periods of middle of the last line of the odd field. for 1080i, this vsync* leading edge must occur between the 1095 th and 1105 th clock on the 563 rd line. r, g, b, and y, p b p r 650 mv 350 mv 50 mv hsync* (input to CX25870) 1 vsync* (input to CX25870) blank* (input to CX25870) time scale compressed. sync and blank period
CX25870/871 appendix e hdtv output mode flicker-free video encoder with ultrascale technology e.12 timing diagrams for hdtv output mode 100381b conexant e-25 figure e-9. proper interface timing between the hdtv s ource device (master) and CX25870/871 (timing slave): broad pulse line in 720p atsc format (raster sel[1:0] = 10) 650 mv 350 mv 50 mv clki [p23?p0] hsync* (input to CX25870) 1 vsync* (input to CX25870) . . . . blank period (generated by controller) 70t (for 720p) 70*(1/74.25 mhz) = 942.8 ns 70t 40t (for 720p) 40*(1/74.25 mhz) = 538.7 ns 40t (for 720p) 40*(1/74.25 mhz) = 538.7 ns 44t low sync period hi-sync period blank period 11 clk pipeline delay 11 clk pipeline delay min. 4 clks min. 4 clks automatically generated by CX25870 broad pulse period (generated by CX25870 encoder) blank* has no effect when either sync* is active or in the tri-level sync period (analog outputs) r, g, b, and y, p b p r 700 mv 100381_071a note(s): a. CX25870/871 automatically generates a broad pulse level and timing. if a blank* signal is not used, adhere to notes b. and c. b. r, g, b, and y digital samples have to equal 00 hex = 0 decimal for the blank period. c. pr and pb digital samples have to equal 80 hex = 128 decimal for the blank period.
appendix e hdtv output mode CX25870/871 e.12 timing diagrams fo r hdtv output mode flicker-free video encoder with ultrascale technology e-26 conexant 100381b
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