I have an interest in retro hardware and have been experimenting with replicating the original 8088 based PC on a set of PCBs for my own fun and education.
This is a very interesting card, in that I understand that it can replicate the floppy drive?
My design is simplified in that I did not implement DMA, as I felt it unecessary. The Tandy1000 also omits DMA and was nevertheless able to read and write data from/to the floppy disk controller IC (and was the inspiration). Unfortunately I have run into problems trying to get floppy I/O to work.
Again I get the impression that this card doesn't have DMA, so I wondered if the "virtual" floppy was accessed via I/O ports?
Sorry if my assumption is way off base(!), but if the "virtual" floppy doesn't use DMA, then presumably use of this card would need a custom BIOS or possibly an option ROM (which I again assume that it can emulate) to allow the INT13 floppy/HDD routines.
I just wondered if this card might be a way to help me get my hardware to boot DOS? I have my own minimal BIOS so I can change the floppy disk code if there was some alternative I/O based way of accessing the floppy hardware. I was already thinking about doing something similar to give me an I/O based floppy interface, speed is not an issue for me, possibly using a Teensy in a similar way. But there's no need to re-invent the wheel!
Again apologies (I found information unclear), but what bus speed does this card support? Does it stall the CPU using RDY/wait to extend bus cycle for faster CPUs?
Many years ago I figured a way to use a PIC to emulate a small specialised ROM chip which was no longer available and I had to find a way to return the data quickly enough for it to be read correctly. Thankfully the ROM it replaced was quite slow. I get the impression that the PICO must be doing something similar, but emulating both RAM and ROM and I/O ports?
Perhaps I should join the discord?
Anyway I think it is a fabulous project and yet another clever way of using modern cheap hardware to emulate parts (possibly unobtainable or expensive) of a retro computer. I am sorry to hear that the author was disappointed at the lack of initial enthusiasm from the retro community.