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hoglet67 / RGBtoHDMI

Bare-metal Raspberry Pi project that provides pixel-perfect sampling of Retro Computer RGB/YUV video and conversion to HDMI
GNU General Public License v3.0
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TI99 4/A TMS-RGB Palette.. #358

Closed dabonetn closed 4 months ago

dabonetn commented 6 months ago

I'm trying to get a NTSC TI99/4a working with the RGB2HDMI using a TMS-RGB. I've got the latest analog board from Retrohack shack.

I'm getting a nice stable picture using a modified Camputers Lynx profile, But the colors are off.

sampling=5,5,5,5,5,5,5,0,1,0,5,0,0,0,0,0,0,0,0,0,100,256,100,256,100,256,256,256 geometry=60,25,256,252,280,286,3,2,3,0,6000000,384,5000,312,4,0,0

Screen Capture. capture0

Emulator output showing proper colors. TI99-4A_Win994a_Simulator_Startup_Screen

Suggestions on where to get started?

IanSB commented 6 months ago

@dabonetn

Getting the TI99/4a fully working with an analog RGBtoHDMI is quite difficult because the video voltage levels are a bit too close together to separate reliably. I have got it fully working both with a direct connection to the YUV output and using the TMS-RGB but the levels need adjusting as it warms up so it is not really a good solution.

However a lumacode board for the TI99 and other systems using the same video chip like the Colecovision has been developed and I now have a prototype for testing so that should be available in the future.

dabonetn commented 6 months ago

I just saw about the TMS board yesterday on his github. Can't wait.

IanSB commented 5 months ago

@dabonetn FYI: https://github.com/c0pperdragon/LumaCode/issues/13#issuecomment-1902838176

dabonetn commented 4 months ago

Lumacode bought and installed... Works great. This can be closed.