A/UX generic SCSI driver and Syquest 44Mb removable drives

[A. Lester Buck]

In article <eakdo#+=michael at xanadu.COM>, michael at xanadu.COM (Michael McClary) writes:
> Turned out the Quantum firmware (6.8 00) had a bug.  When disconnecting, it
> neglected to tell the initiator to save pointers. Come the reconnect, blooie! 
> Solution was to get new firmware from Quantum.  ((7.9 00) fixes that bug,
> 
> Suggestion for Apple:  Think seriously about having the SCSI driver save the
> pointers even if the drive doesn't ask you to.  Sure, it means a little more
> code, to support somebody else's bug.  But the bug doesn't manefest under
> finder, so when it shows up under A/UX it looks like YOUR fault, not the
> drive's.

Sure, and break all those drives that *do* conform to the SCSI-1 standard!

The updating of the SCSI pointers is a tricky business, and the target
controls everything in a SCSI transfer.  Just for example, what if
the target detects and recovers from an error, and needs to resend some
data - it disconnects and reconnects WITHOUT saving the pointers.
In SCSI, the action of saving pointers means at least that much
data is, in the target's opinion, error free.

Just because some clowns at Quantum didn't simultaneously
test run two of their drives on a single bus (by rev 6 of their
firmware, yet!), don't ask Apple to destroy their own systems.

-- 
A. Lester Buck		...!uhnix1!moray!siswat!buck