The ISA slot is implemented in Verilog. What I'm thinking of doing is implementing a few Verilog programs that set up various graphics modes and write something into video memory.
Almost like a game cartridge! You could just connect the one you want in the simulation and then run it, and you'll see the card do something different.
The CGA had an alternate thin font.
Here it is on top compared to the normal font beneath it.
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