I looked about XBIOS function DMAread, what is present at TOS 2.06 . I know that it is used by AHDI and Hddriver for loading second stage of IDE hard disk driver, so it must support IDE disk access too, even if it is not in DMA mode . And it seems that all available DOC online is not complete about it.
toshyp.atari.org says that it is only available at TOS 3.* - and that's wrong - we know that there is IDE support in 2.06 .
Looked some other DOCs - Atari Profibuch latest release, Compendium, etc. and none of it contain info what is device code for IDE port - for IDE master - and it is $10 - what follows after $F for last SCSI dev.
I examined this many years ago, when added IDE autoboot code for diverse TOS versions. And it worked only with my drivers - because my IDE driver does not use XBIOS 42 (DMAread), but direct HW access. So, I think that I will add it to improved TOS 1.04/1.62 - but only IDE code, just to make AHDI and Hddriver working with IDE on TOS 1.xx .
Just another case, where I could not find required data in available (and often glorified) TOS documentation online. Instead it needed some longer trace and smaller test SW to realize how to properly use it - and in my case how to add that function in TOS 1.04/1.62 .