Hi, Thanks again for this great emulator.
I think the VGA VRAM is not wrapping correctly on mode 13, (the one with only 64 Kb).
Well, it wraps, but It always thinks the vram is 256 Kb (mode X) and I have to scroll 4 pages down until it reaches address 0 of VRAM again.
Here you see a screenshot from Dosbox (it works the same on real PC), and a screenshot using PCem, Also include a test program.
Thanks a lot.
VGA VRAM Wrap
VGA VRAM Wrap
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- DosBox.png (10.3 KiB) Viewed 5123 times
Re: VGA VRAM Wrap
Well the code was tested it on a real VGA, and PCem is working OK. So that's not a bug, it just does not wrap around 64 KB but 256 Kb.
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SarahWalker
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Re: VGA VRAM Wrap
I suspect this varies from VGA board to VGA board. Which real board was it tested with?