Oh, please tell me more.
OK, it uses the EXT bus only, and as Bonknuts says, it gets the video signals while they are still digital for an effectively flawless picture.
It's only possible on systems with the EXT bus, although he says that with some effort, you could probably still attach a CD-ROM system.
1024x768 is a standard XGA resolution, and 1280x720 is standard 720p. Games that are 256 pixels wide can be multiplied by 4 to fit 1024 exactly, while games that are 346 pixels wide like R-Type can be multiplied by three to fit in 1280.
He says something about a black and white function, which I can't accurately paraphrase because I don't completely understand the technical details. Does the system have an internal function that can make all the graphics black and white (greyscale)?
The sync coming from the system is either 59.82Hz or 60.05hz, depending on what the game sets. Digital signals are an even 60Hz, and this causes the frame problem. He doesn't say specifically that his setup drops a frame, but rather that something "goes off" about every six seconds. It might just be tearing.
He says he tried various things to fix this, but in the end, there is no solution that allows perfect stability and perfect sync. It's impossible short of altering the internal timing.
He'd like to know if there's a hucard, not a CD game, that frequently changes the VCE register at address 0x1fe400/bit1:0 for testing.
He'd like to know more about VCE register bit2.
And any games that use the VCE in weird ways.
The guy in the comments says that bit2 has to do with countering the color jittering you see when the screen scrolls in composite video. The writer replies saying he'd like to learn about games that use this register.