Hi Paul,
I don't have a s-video cable at the moment but when I probe the luma and chroma I see a signal coming out. I suspect it looks like the composite output (grayscale color bars). If I make changes to register E42A (not E42B), I can make the output from DAC4 change to chroma, luma, or CVBS. I have mapped the DAC correctly.
Do you have an example script that sets up the ADV8005 and has successfully generated the color bar test pattern out of a SD encoder DAC supplied with CVBS data?
Thanks.