🚀 go-pugleaf

From: dal@syntel.UUCP (Dale Schumacher)

[trb@stag.UUCP ( Todd Burkey ) writes...]
> In article <28@umvlsi.ECS.UMASS.EDU> kimmel@umvlsi.ECS.UMASS.EDU (Mathew Kimmel) writes:
>>I've heard that the current version of Minix ST will not talk to Supra
>>hard disks.  However, I've also seen a message from someone who says he
>>uses a Supra hard disk with Minix ST and has no problems.  I'm not sure
>>what to believe, but I'd like to know the answer before I buy Minix.
>>Can the current version of Minix ST talk to a Supra hard disk?  If not,
>>is there a patch available that I could apply to the operating system to
>>fix this?
> 
> A friend just bought his second 30MB Supra recently and discovered that the
> newer one works fine under Minix, but the older (8 months old) Supra
> doesn't. He is using the same format/utility software for each, and
> the only obvious difference is that the drive types were different (I
> think he said the new one was Seagate and the old was Miniscribe). The
> drive type shouldn't affect operation, so there must have been other
> changes in the ST-SCSI adapter as well. I hear that Supra is working
> on the problem, so hopefully there will be a software fix for the older
> drives.

Well, the answer is "all of the above".  Some of the newest Supra hard
disks DO work just fine with Minix-ST, as does the Atari Hard Disk.  Tony
Andrews (Sozobon C) has been using Minix-ST with an Atari drive for several
weeks now and it is "rock steady".  I on the other hand have had no end
of troubles with Minix-ST and my VERY old Supra 20 (full height even).
I've also been having other problems with my machine, such as the compiler
getting and "illegal instruction" trap on one try, and working find the
next time with the same source, so I'm not in a good position to recompile
the kernel over and over.  Tony has been doing recompiles for me and
uploading (50K at a time, long distance) new versions.  I've also been
in almost daily contact with Willie Brown, from Supra Corp.  Willie wrote
most of the ST hard disk code from Supra.  Supra as a whole has been VERY
cooperative and supportive, which is nothing new for them.  I've ALWAYS
gotten GREAT customer support from them (unlike SOME companies).

Anyhow, after many trials and errors, I've managed to patch together a
kernel which can read and write my Supra drive, however it's very unclean
in it's implementation, so I'm not going to be posting my changed yet.
We still haven't figured out what is really going wrong, but we are making
(slow) progress.  The current hard disk driver is hand-optimized assembly
(the ACK compiler creates unbelievably bad code) and forceably ignores
panic()s causes by spurious hardware interupts.  Also, a change in the
code, (first attempt to remove the panic, actually) which changed the code
size by 10 bytes, caused it to fail again (alignment problems?).  So it's
obviously not something everyone wants to use right now.

I really wish I had better news.  I want my hard disk working just as badly
as everyone else, but it's going to take some time.  This appears to be a
very subtle bug.  If anyone else has gathered any useful information, I'd
be happy to hear from you.  Our efforts are temporarily on hold until after
Comdex.

PS.  A piece of advice.  Minix is not yet ready for general "users".  If
you like hacking on system software and working with an unstable environment,
go ahead and get Minix, it is really a nice toy.  Lot of nifty software
should start popping up as the initial bugs are worked out.  My first
major Minix project will probably by uucico, mail and news... as soon as
I get this hard disk problem fixed :-)

--
      Dale Schumacher                         399 Beacon Ave.
      (alias: Dalnefre')                      St. Paul, MN  55104
      ...pwcs!stag!syntel!dal                 United States of America
    "It's not reality that's important, but how you perceive things."