TRH9000 - The Yamaha V9990 based open-source video card for the MSX

I agree. I would use a custom cable anyways but please use something that is real sturdy on the cartridge side.

Will it only accept RGB in? Or is composite also an option? I mean most of the MSX1 computer don't have RGB. Just asking, it will be great either way!

New update. First test batch arrived, and the first TRH9000 was built.

Still not with the full superimpose circuit, but with the appropriate places for connectors and ICs to allow further testing and validation. We are very close to release a full compatible GFX9000 card using the LMH1980 sync separator instead of the old CXA2075 encoder. Still need to perform a few corrections and adjustments to make sure the board offers good video quality.

First superimpose test was not successful tough. Not getting a superimposed screen and I believe is due to the signal we need to provide back to the V9990 to sync the image. Picture below shows the image I'm getting when attempting to superimpose.

Lots of tests during upcoming weeks.

Make sure you have a good ground plane in this design. The second generation gfx9000 card has very bad grounding resulting a seeing vertical lines in sync with vram access of the v9990 (or something like that).

Why, these modes are not supported internally by the V9990!? Do you need extra components to use them?
Do the other V9990 cards support these modes?

I started a sample program for MSXgl to check all the V9990 features but for the moment, I only tested all pattern modes relative features.

Also these modes will not work on scart. For it to work you need a vga output. iirc v9990 has a composite sync singal, which needs to be split to a hsync and vsync for vga modes.