Per our previous discussion, I will try bypassing the pre processor (SAA7111) that does the analog to digital conversion. Patching the RGB binary wighted signals from the IIgs graphics chip into the AL250 directly and wire it for RGB565 processing.
Granted the graphics chip in the IIgs only puts out 4-4-4, but we can experiment by tying the extra inputs high and low to get the best results.
If I ever get the time ot do this, I at least now have all the pieces. It may end up being my K-fest hack project.
Reference previous discussion: http://groups.google.com/groups?hl=en&lr=&ie=UTF-8&oe=UTF-8&th=85bc3022f0c0078a&rnum=1 Michael J. Mahon wrote:
I tried a "Video Cheese Box" (Yes, really ;-) and was quite disappointed with the quality of the conversion of lowly composite video to VGA. The composite format, like the S-Video format, is fundamentally incapable of carrying the information to make a crisp IIgs display, so our hopes must be pinned on direct RGB or component video.