Hi everyone !
At spare time I'm trying to create something VERY compatible with PC XT. The design is using modern FPGA (currently Altera Cyclone IV on DE2-115 development board, but it doesn't really matter) with real 8088, 8284 and 8288 chips.
At the moment I have almost 100% CGA-compatible video adapter (on register level) with output to VGA monitor (using 640x400 mode - every CGA pixel takes 2x2 of VGA pixels), so I'm using original XT BIOS almost for everything, except FDD and HDD.
I'm using my own int 13h BIOS handler to emulate HDD on SD card, and everything is working quite well. Tried more than 20 old classic games, they work quite well (including MS Flight Simulator and Lotus 1-2-3 that were used as a compatibility test for early IBM-compatible PCs).
Actually, I have one related question - does anyone aware of something like virtual FDD for DOS ? I wasn't planning to emulate FDD for now, but discovered that a lot of old software does exist on FDD images only and would not run from HDD. Quick search did not find anything for DOS - for Windows only... I can try to make my own emulator, but right now have too many other things to do...
And just for fun, a few pictures:
At spare time I'm trying to create something VERY compatible with PC XT. The design is using modern FPGA (currently Altera Cyclone IV on DE2-115 development board, but it doesn't really matter) with real 8088, 8284 and 8288 chips.
At the moment I have almost 100% CGA-compatible video adapter (on register level) with output to VGA monitor (using 640x400 mode - every CGA pixel takes 2x2 of VGA pixels), so I'm using original XT BIOS almost for everything, except FDD and HDD.
I'm using my own int 13h BIOS handler to emulate HDD on SD card, and everything is working quite well. Tried more than 20 old classic games, they work quite well (including MS Flight Simulator and Lotus 1-2-3 that were used as a compatibility test for early IBM-compatible PCs).
Actually, I have one related question - does anyone aware of something like virtual FDD for DOS ? I wasn't planning to emulate FDD for now, but discovered that a lot of old software does exist on FDD images only and would not run from HDD. Quick search did not find anything for DOS - for Windows only... I can try to make my own emulator, but right now have too many other things to do...
And just for fun, a few pictures:
Last edited: