Subject: Re: Installer/Disk Problem
To: Alan C. Bindemann <davagatw@Mars.utm.edU, bindeman@tsun.eglin.af.mil>
From: Mark Andres <mark@giganet.net>
List: port-mac68k
Date: 01/03/1997 21:41:29
The IIcx (and a few other models I believe) are strange in that they have
no internal termination.  The only reason I know this is that I have a IIcx
which I am using to run NetBSD.  Alan's message mentions a CD-ROM which I
assume is external.  The question is whether the hard drive is also
external or internal.  

If the Lightning 730 is an external HD, ythen you should use an active
terminator on the end of the SCSI chain with the CD-ROM.

IIcx --> CD-ROM drive --> active terminator.

If the Lightning 730 is an external HD, then you should probably use active
terminators on both ends of the *external chain*.  I know this doesn't seem
like it makes sense, but it will improve SCSI performance.

IIcx --> terminator --> HD --> CD-ROM --> terminator.

I was originally using my IIcx as a scanning station in this configuration:

IIcx --> External HD --> SCSI Scanner --> terminator.

I had all sorts of problems with my internal HD until I added the active
terminator between the IIcx and the external HD.  

Mark

At  0:46 PM 1/2/97 -0600, The Great Mr. Kurtz [David A. Gatwood] wrote:
>Am error like that at the beginning of installation (mounting) is normal.
>An error like that during the installation, AFAIK, is not.  The first
>thing I'd suggest checking is SCSI termination.  The internal drive at ID
>0 should be terminated already, which takes care of the beginning end of
>the chain.  No other drives on the chain should be terminated except the
>last device.  Also, try changing SCSI cables.  Some lower-quality SCSI
>cables can introduce noise into the system that may be covered up by
>MacOS's error checking.  Finally, "pass-through" terminators may not work
>satisfactorily.  Switching to terminators with only one connector may help
>matters, and switching to active termination may improve things 
>significantly under some circumstances.
>
>Of course, that may not be the problem.  It could simply be a strange
>software issue.  No way to be certain.  Thoughts, anyone?
>
><snip>
Mark Andres                  Head, Support Dept.
           GIGANET by Business Network Telecom (BNT)
E-mail:  mark@giganet.net    URL: http://www.giganet.net/staff/mark/
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