Newsgroups: comp.sys.mac.hardware
Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!zaphod.mps.ohio-state.edu!magnus.acs.ohio-state.edu!pat
From: pat@magnus.ircc.ohio-state.edu (Patrick E Plaisted)
Subject: Re: Both hard drives on to boot Mac Plus?
Message-ID: <1991Mar27.173936.10638@magnus.acs.ohio-state.edu>
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Organization: The Ohio State University
References: <1991Mar27.050325.3851@schaefer.math.wisc.edu>
Date: Wed, 27 Mar 1991 17:39:36 GMT
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In article <1991Mar27.050325.3851@schaefer.math.wisc.edu> lindhurs@schaefer.UUCP (Scott Lindhurst) writes:
>I just connected two hard drives to my Mac Plus, and now I can't
>boot from one until they are both turned on.  Then the one with
>the higher SCSI id boots.  Either one connected individually
>will boot, it's just that when both are connected, they both
>have to be turned on get the Mac even to recognize their
>existences.

The problem is that one of your drives (almost certainly the old one) 
needs to be powered up in order to provide power to the termination 
resistors.  Even if it's not the last one in the chain, it makes your 
scsi chain invalid unless it's powered up, hence the reason your mac 
won't boot.

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Patrick Plaisted                     |pat@agvax2.ag.ohio-state.edu
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I'm not quite sure who's ideas these are; I think they're mine...