Anyway, thanks for providing the crash_hatari.S source code. Looking at
that file, I wonder whether there is another bug in Hatari: You don't
switch to supervisor mode before accessing the registers ... Is it
possible to access the IDE registers in user mode on a real Falcon? I
don't believe so, but could somebody who has a Falcon easily
available please check this, just to be sure?
At least a lot of third-party IDE interfaces allow register access in
user mode, as well. Furthermore, the STBook was the other Atari with
built-in IDE. It becomes apparent from the STBook schematic that IDE
register access is possible there in either supervisor or user mode.
Hence, I wouldn't be surprised if Atari kept it that way for the Falcon.