DVI to CVBS conversion

1) EDID is only required by the source.  If the source doesn't care about the EDID and pumps out XGA60 regardless then all's good.  You can override the HPD in the ADV7611 and set it up for XGA just fine.

2) For the ADV7611, the output resolution will be the same as the input resolution.  The device will not do format conversion.  It can change the color space and package the output into BT656 or what ever, but the timing remains the same.  If XGA60 goes in, that's what will come out.  Also note that XGA60 is an RGB format so the output will either be RGB 444 or YCbCr 444 on a 24 bit bus.  It doesn't make sense to output RGB on an 8-bit bus in BT656 format since you really can't interleave RGB correctly.

3)  The ADV7611 is the newest part and has the best performance.  It'd stick with it.

4) Originally I thought the DVI input was going to carry a CVBS format (720x480) so I wasn't worried about it.  However now that the input is XGA60 (1024x768@60) and the output needs to be CVBS, these are two different formats.  You'll need some kind for format converter.  XGA60 has a pixel clock of 65MHz while CVBS pixel rate is 13.5MHz.  You can't just feed the 7611 into the 739x and expect it to work.  Either you run the RGB through an FPGA and down convert yourself or get a chip like the ADV8003 which can do the down conversion.

1) EDID is only required by the source.  If the source doesn't care about the EDID and pumps out XGA60 regardless then all's good.  You can override the HPD in the ADV7611 and set it up for XGA just fine.

2) For the ADV7611, the output resolution will be the same as the input resolution.  The device will not do format conversion.  It can change the color space and package the output into BT656 or what ever, but the timing remains the same.  If XGA60 goes in, that's what will come out.  Also note that XGA60 is an RGB format so the output will either be RGB 444 or YCbCr 444 on a 24 bit bus.  It doesn't make sense to output RGB on an 8-bit bus in BT656 format since you really can't interleave RGB correctly.

3)  The ADV7611 is the newest part and has the best performance.  It'd stick with it.

4) Originally I thought the DVI input was going to carry a CVBS format (720x480) so I wasn't worried about it.  However now that the input is XGA60 (1024x768@60) and the output needs to be CVBS, these are two different formats.  You'll need some kind for format converter.  XGA60 has a pixel clock of 65MHz while CVBS pixel rate is 13.5MHz.  You can't just feed the 7611 into the 739x and expect it to work.  Either you run the RGB through an FPGA and down convert yourself or get a chip like the ADV8003 which can do the down conversion.