Date   : Fri, 25 May 1990 09:53:07 PDT
From   : rzh@lll-lcc.llnl.gov (Roger Hanscom)
Subject: Xerox 820... upgrade to DS/DD

Sorry to post this, but e-mail to ficc.ferranti.com failed.

Peter da Silva writes:

>I have a Xerox 820 with 2 SS/DD drives.  Can I just get a couble of cheepy
>IBM-PC 360K drives and stick them in there to get DS/DD, or is there some

Unfortunately, Peter, the 820 is based on the WD 1771 controller which is
SD *only*.  There are (were?) upgrade kits available for this beast to
make it DS/DD (390K on 5.25" diskettes).  When applied to the 820, it
thinks it's a Kaypro.  I did one, and jumped the clock to 5 MHz.  The
result is a really nice machine!  The vendor had connections to MicroC,
and was located in Aloha, Oregon.  I can get more info, if you're in-
terested.
It also may be possible to put two DS drives on the vanilla 820, and
use sides as logical drives, i.e. A: is drive 1 side 1, B: is drive 1
side2, C: is drive 2 side1, etc.  This works best with 8" drives, but
I think that you'll have only about 250K per side because each side
is formatted as standard SS/SD (26 128b sectors/track, 77 tracks).

            roger                 rzh@lll-lcc.llnl.gov

Q:  Know the difference between a terrorist and a woman with PMS?
A:  One can negotiate with the terrorist!


End of INFO-CPM Digest V90 Issue #93
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