17 Jan
2011
17 Jan
'11
9:15 p.m.
On Mon, 17 Jan 2011, Sridhar Ayengar wrote:
Steven Hirsch wrote:
Thanks to all who responded! It turned out to be two problems:
- Active termination. I've run into this before and should have
remembered. Turning on termination at the drive (at least with IBM
drives) simply renders the entire bus non-functional.
- Synchronous negotiation. This was the default setting for both drives
and it apparently must be disabled.
Once I made those two changes together, bingo! Back to life. I'm busy
installing A/UX right now.
Steve
--
Here's the odd part: With the original
Apple-branded OEM Quantum drive
(which I do not want to overwrite) on the SCSI bus the installer
recognizes the CD-ROM and is willing to begin the process. However, with
any of the third-party hard drives in the system it is unable to
recognize _anything_ on the SCSI bus - doesn't see the hard disk or the
CD-ROM. I've checked and double-checked the jumpering on the hard disk
and it's not conflicting with the CD-ROM. Both the IBM and Fujitsu are
fairly run-of-the-mill 50-pin SCSI units.
Did you only check the SCSI ID jumpers, or did you also check the termination
and termination power jumpers? Multiple devices providing terminator power
can sometimes cause this symptom, especially if the SCSI bus arbiter is a bit
sensitive.