Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!rutgers!apple!dwells
From: dwells@Apple.COM (Dave Wells)
Newsgroups: comp.sys.mac
Subject: Re: Hard disk hardware question
Message-ID: <32436@apple.Apple.COM>
Date: 15 Jun 89 03:51:56 GMT
References: <32402@apple.Apple.COM> <8400120@m.cs.uiuc.edu> <25473@agate.BERKELEY.EDU>
Organization: Apple Computer Inc, Cupertino, CA
Lines: 34

In article <25473@agate.BERKELEY.EDU> lippin@math.berkeley.edu writes:
>I've just started using a Mac II with a 40MB Apple internal hard
>drive.  Unfortunately, my old hard disk, an old and clunky 20MB LoDown
>external, can't be mounted together with the internal drive.  I
>suspect the problem is that both are set to use SCSI ID 0.  Neither
>drive has a convenient way to change the SCSI ID, so I'm looking for
>an inconvenient way.
>
>The LoDown has a controller board labeled OMTI 3100, which has a large
>number of jumpers, some of which might be used to change the ID.  Does
>someone know how to do this?

The OMTI 3100 does have a set of jumpers dedicated to SCSI ID addressing.  If
I remember right, they should be located toward the center of the board,
offset diagonally about an inch or so.  If the drive is really set to ID 0
then there should be no jumpers on any of the pins in this set.  It's a
binary configuration, so the first set (on the SCSI cable end I think) would
generate a 1 and the 3rd set would generate a 4.  If you want 6, put jumpers
on the 3rd and 2nd set.  I've started from the wrong end before and not
harmed anything, so this shouldn't be a problem.  Just try again.  (Standard
disclaimers apply)  You'll have to power off the drive each time you want
to change these jumpers or the change won't take effect (besides the increased
risk of ruining something.)


-Dave

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           Dave Wells, Apple Computer, Inc.  MS: 37-O  (408) 974-5515
          Mail: dwells@apple.com or AppleLink d.wells or GEnie D.WELLS
 These opinions may be nothing more than the ramblings of a fatigued tinkerer
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 There's one big difference between genius and stupidity.  Genius has limits.
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