Re: SCSI Strangeness

[gtolar@blkbox.com (Glynne Tolar)]

Jim Wong (jd-wong@uxa.cso.uiuc.edu) wrote:
: I'm experiencing some bizarre SCSI behavior with my GS; I have an
: Apple High Speed SCSI card, a 20 MB Seagate drive, and a 105 MB
: Quantum disk.  The Seagate is the last device in the SCSI chain and is
: internally terminated.

Well, my first stab at this would be to attack the Apple HS SCSI card.  
Since it does not supply TERMPWR to the SCSI bus.  This is usually where 
SCSI problems reside when the Apple card is involved.  And I'm almost 
sure the Quantum need it.  The Seagate (for all the times I've hated the 
one I use to have) does not require TERMPWR since it supplies it own.

Solution, get a RamFAST.  Ok, I know...  Well you could modify the HS 
SCSI or the Quamtum to supply TERMPWR, but without qualified help I'd not 
recomend it since you could harm your card and/or drive.

: When I boot from the smaller drive, everything
: seems to work perfectly.  On the other hand, when I switch the drives'
: SCSI id's to boot GS/OS from the Quantum, my machine crashes at
: seemingly random points during the boot process, sometimes dumping me
: into the monitor, sometimes simply hanging, and sometimes generating
: error messages like "Unable to load TS 2..." or "...Apple Disk 3.5
: requires a driver..."; if I press the space bar to see what's being
: loaded, it occasionally dumps inverse characters all over the screen as
: the system heads south.  Booting ProDOS 8 by holding down the pressing
: the "8" key seems to work, however.  Can anyone explain this odd
: behavior?