Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!iuvax!cica!tut.cis.ohio-state.edu!ucbvax!SOLARVAX.UMD.EDU!allon
From: allon@SOLARVAX.UMD.EDU
Newsgroups: comp.sys.mac
Subject: Hopping on the SCSI bus (uptown)
Keywords: SCSI, scsi, ScSi, sCsI, Scsi, sCSI (who cares, except uNiX machines?)
Message-ID: <8907312149.AA18252@ucbvax.Berkeley.EDU>
Date: 31 Jul 89 22:50:00 GMT
Sender: daemon@ucbvax.BERKELEY.EDU
Organization: Prune Bran
Lines: 28

In Article 38747 jjs@PRC.Unisys.COM writes:

>1. Must (should?) all SCSI devices on the chain be powered up when
>   the system is running.  I had assumed this was false, now I am not so
>   sure.  Can devices on the chain be selectively powered up in general?

Well, I dunno, but some friends of mine were having a problem getting their
Mac IIx to boot from the hard disk -- it didn't even recognize the disk.
We even opened it up and checked that the connectors were tight.  Finally,
we tried turning on all the SCSI devices, the CD rom, the scanner, everything,
and it worked fine.  I guess the answer might be yes, at least in some cases.

On the other end, I was trying to get a Mac+ to boot from one hard drive and
not the other (both external).  I turned one off, and it booted from the other
one fine.  The answer might have something to do with where the terminators
are, and what the SCSI addresses are, but I don't know.  Anybody know?

                               - -= Allon =- -

BLISS is ignorance

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Disclaimer:   I don't really think anybody here cares about my opinions, or even
              knows that I have any.

Internet: allon@solarvax.umd.edu      SPAN:  UMDSW::ALLON
          allon@uap.umd.edu                  UMDUAP::ALLON
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