Help needed: multiple HDU's on PC6300

[David T. Punia]

We're setting up a PC6300 as a small file server, and have been
considering two different angles. We could dive right in and get the biggest
drive we can find, but it seems the smaller drives have become such a
commodity item that the cost per bit isn't necessarily lower for the higher
capacity units, as used to be the rule. So, at least for now, we're opting
for putting a number of smaller, cheaper 10 and 20 Mb drives on. The
redundancy is nice to have, too.

To get to the point, we've got two 10 Mb and one 20 Mb drives running off
two of AT&T's HDU Controllers. Well, not running, really. We can get the
switch settings right to allow the power up diagnostics to tell us that there
are three drives out there, but DOS (MS 2.11) fails to boot. Several calls
to ATTIS's hotline failed to help us much. We've got version 1.21 ROM,s and
all three HDU's are AT&T issue, collected from other PC6300 hard disk
systems. Has anyone out there had any luck with this type of configuration?
We did find that we had to cut an I/O address jumper to get the second
controller's disk to be found, and that made sense to us, but the DIPswitch
table in the AT&T hardware reference manual is unfathomable. We've yet to
try 1.43 ROMS, but the hotline made no point of mentioning it. Any ideas?

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"Thunder is good, thunder is impressive;
but it is lightning that does the work." Mark Twain (1835-1910)
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David T. Punia, Dept. of Computer Science & Electrical Engineering
The University of Vermont, Burlington, VT 05405-0156
802-656-3330

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