Found another good description:

ftp://ftp.seagate.com/acrobat/reference/111-1c.pdf

My emulation is based on two specifications only: ATA-1 for emulated harddisks and ATA/ATAPI-4 for CD-ROM drives(still buggy for some unknown reasons).

Yes, both are combined into a single version, using either ATA-1(HDD only) or ATA/ATAPI-4(CD-ROM only). And even so, only implemented the mandatory commands(and read/write many commands, since XT-IDE strangely seems to assume they exist with autodetection, even though they aren't mandatory).

superfury wrote:

Yes, both are combined into a single version, using either ATA-1(HDD only) or ATA/ATAPI-4(CD-ROM only).

Yes that is fine. I will be doing exactly the same thing. However when you learn that is a bit less clear 😀

superfury wrote:

And even so, only implemented the mandatory commands(and read/write many commands, since XT-IDE strangely seems to assume they exist with autodetection, even though they aren't mandatory).

That makes sense. My aim will initially be the same.

I would have suggested older ATA specifications and OSDEV articles/examples about ATA storage devices.

Me, too. Personally, I'd also make sure good WD1003 compatibility is assured.
http://geekscomputer.blogspot.de/2008/07/ata- … mmands-set.html
http://www.vcfed.org/forum/archive/index.php/t-41445.html

Edit: Also have a look at an older release of PCE. If you need more documentation, have a look at archive.org.
Magazines and PC repair/compendium books from the mid-80s do often contain valuable information.

Thank you Jepael and Jo22, those are good pointers. I'll see if I can compile a list of resources and put it here for other to use.