there's another thread about CD-ROM drives and the XTIDE somewhere here.
Essentially it boils down to this:
1) Our XTIDE hardware is unique. We use a nonstandard way of getting data to-from the drive. We do that because we have to in order to get 16bits of data down to our 8bit ISA bus.
2) because of #1, no existing CD-ROM.sys driver is going to be able to talk to a CD drive attached to XTIDE. Another gotcha is that most CD drivers use 386 instructions, which we can't do either.
3) I'm ~90% sure that there aren't any hardware/signal issues that would stop us from reading CDs on the XTIDE. There may be some gotchas with regard to our missing alternate status register that I haven't yet come across.
4) I am actively (when the g/f allows me to work!) working on writing a simple test chunk of code to try and read a sector off a CD. Once I can get that done, I will need to write an entire .sys driver file that you would need to load in your config.sys to get CD support on the XTIDE card. It's a big job, and I've never done real CD work at this low level before, but I am absolutely going to try. If there are no hardware issues with XTIDE itself to get CDs working, then we should absolutely move into production on XTIDE. If there are changes that need to be done, then we're sitting at another prototype cycle. I think CD support is important enough to delay production if it's a feature we can add.
Edit: oh, booting off a CD is a whole different beast. I doubt there is enough room in our 8k BIOS (especially after we add HD FDD support) for the code required to boot. Not ruling it out, but it's a long shot.
BTW: I ate at the very mexican restaurant that the "el torito" CD specification document was named after.
http://en.wikipedia.org/wiki/El_Torito_(CD-ROM_standard)
