Re: What's wrong with Revision B SCSI?

[dempson@actrix.gen.nz (David Empson)]

The Byter <cabalslexicon@hotmaill.com> wrote:

> Well, after a few trials I did get it working with GS/OS 6.0.1.  Is it
> only the format thing, or is there some other problem I should be
> seeing?  Is it possible that I have updated firmware?  How do I tell?

If you were able to boot into GS/OS without patching any system
software, then it is most likely that you already have the revision C
firmware.

If you have an original Apple SCSI card with revision A or B firmware
and you try to boot GS/OS, you will get an error message about the
firmware not being supported, and the card will be ignored.

There is a possible exception to this: if you booted from the hard drive
_and_ you don't have the SCSI drivers installed on the hard drive, then
GS/OS might let you boot with limited functionality: you won't be able
to access anything except the first partition (and floppy drives).

This is how it behaves with the High-Speed SCSI card (or revision C
firmware in the original card) if you don't have the SCSI drivers
installed.  I'm not sure whether the check for the revision A/B firmware
is part of the system itself or part of the SCSI drivers.

If you boot from a floppy which has no SCSI drivers, the SCSI card is
ignored completely, no matter which firmware revision it contains.

To check the firmware revision of your card, look at the label on the
EPROM (assuming it is an original Apple EPROM or has at least been
labelled correctly if burned by someone else):

341-0112A is revision A
341-0112B is revision B
341-0437-A is revision C