3B2 Hard Drives

[Philip A. Gross]

flynn at clotho.acm.rpi.edu (Kevin Lincoln Flynn) writes:

>We have a problem.  We've a 3B2/400 with two 72MB drives (CDC Wrens, unless I
>misremember), and we cannot format the disks with idtools.  We say 'formhard'
>and enter the defect table, and then spits 'cannot read physical info' at us
>and quits.  Help!  We need this machine....  any information anyone has would
>be greatly appreciated.  Schemes which rely on running DOS boxes, 3B2/300s,
>/400s or a 3B15 can be implemented.

The first thing to check out here is to make sure that the drives are
addressed properly and that the resistor pack is properly installed.  The
resistor pack must be installed on the LAST drive in the chain.  You will
find a socket at the rear of each drive that can accomodate the resistor
pack.  Next to the socket is a set of Burge (sp?) jumpers.  As I recall,
the jumper farthest from the resistor pack will address the drive as 0.
Typically, the first drive in the chain is drive 0 and the second/last is
addressed as drive 1.

Next, when using idtools, I would suggest that you first select the option
for entering the defect map of the drive(s) only.  Then, if this succeeds,
proceed to the formhard option.  The formhard option should then present
the defect map information that you previously entered.  It is also
important to make sure that you describe the drive properly.  The description
of a CDC Wren II is as follows:

		Drive ID: 5
		512 bytes/sector
		 18 sectors/track
		  9 tracks/cylinder
		925 cylinders
		923 user accessible cylinders

Hope this is of some assistance.
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Philip A. Gross       The Computer Solution Co., Inc.       Voice: 804-794-3491
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        The opinions expressed here are strictly mine and nobody elses.
        << I haven't heard what I have to say about that yet. >> :-)
-- 
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Philip A. Gross       The Computer Solution Co., Inc.       Voice: 804-794-3491
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INTERNET:	pag at tcsc3b2.tcsc.com