85mb Micropolis in a Microvax II?

From: Jerome Fine <jhfine_at_idirect.com>
Date: Sun Nov 22 15:38:00 1998

>Daniel T. Burrows wrote:

> The RD53's were Micropolis 1325's. If you can find a 1325 you need to
> install a jumper in R7 location on the main board to make it look like an
> RD53. Also install jumper blocks on W1, W2, and DS3.
> Dan

Jerome Fine replies:

Almost correct, as far as I know, but if you do so, you will likely
lose DUA0: if it is not WRITE PROTECTED when you boot.

IF YOU ARE USING TWO HARD DRIVES IN A BA23
BOX, YOU MUST!!!!!!!!!!!!!!!!!!!!!!!!!!!!!! SET THE SECOND
DRIVE AS DS4!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

The last time (and only) I set both drives on DS3, I lost the format
on both and could not recover DU0: - it was on a PDP-11, but
I doubt that the DS3 / DS4 setting requirements are different on
a uVAX II.

Note that the settings on a BA123 with the special I/O distribution
board in slot 13 are very different in that 4 hard drives are allowed
of you don't have any floppies AND all hard drives are set for DS3!

> -----Original Message-----
> From: Computer Room Internet Cafe <netcafe_at_pirie.mtx.net.au>
> To: Discussion re-collecting of classic computers
> <classiccmp_at_u.washington.edu>
> Date: Sunday, November 22, 1998 5:36 AM
> Subject: 85mb Micropolis in a Microvax II?
>
> >Hi all,
> >
> >Just pulled a Micropolis 85Mb MFM Hdd out of a genuine, but dead, IBM 286.
> >Model is 1335, and is also marked as being an ST506.
> >Am I correct in assuming it would work in a Microvax II that presently has
> >a single RD53, as a second drive?
> >If so, is there deep magic involved in the install?
> >I seem to recall seeing something about needing special
> >software that is not supplied with the Microvax to put in a
> >non DEC drive.
> >The Microvax is currently running VMS 5.4
> >
> >TIA
> >
> >Geoff Roberts
> >Computer Room Internet Cafe
> >Port Pirie
> >South Australia.
> >netcafe_at_pirie.mtx.net.au
> >

On a PDP-11, there are DEC formatting programs, but I don't know
what you use on a VAX/VMS? I suggest that you take great care.
I also suggest that you either backup DUA0:

Also, the format for an RD53 on an RQDX2 is incompatible with the
format on an RQDX3.

Sincerely yours,

Jerome Fine
RT-11/TSX-PLUS User/Addict
(Almost no one wants Y2K Patches for any version of RT-11)
Received on Sun Nov 22 1998 - 15:38:00 GMT