Multi-platform distribution format (Was: Backups [was
bqt at update.uu.se
Mon Sep 21 11:47:02 CDT 2015
On 2015-09-21 18:34, Paul Koning wrote:
>> On Sep 21, 2015, at 12:28 PM, Jay Jaeger <cube1 at charter.net> wrote:
>> On 9/21/2015 4:30 AM, Johnny Billquist wrote:
>>> On 2015-09-21 02:11, Jerome H. Fine wrote:
>>>>> Chuck Guzis wrote:
>>>> Note that the RX50 was the same. DEC finally changed
>>>> their marketing policy with the RX33 drive which used the
>>>> same 3.5" HD floppy media as the PC. It was actually
>>>> possible to FORMAT those floppies under RT-11.
>>> No, DEC actually did support users formatting RX50 floppies on their
>>> own, but only on the Rainbow.
>> There was also a standalone PDP-11 diagnostic program available that
>> could do it.
> For RX50? On standard PDP11s, those used an MSCP controller, which means the controller would have to do it. Did it? The only MSCP controller I remember that did formatting was the UDA50.
For Unibus, the controller would be the RUX50. MSCP, as you say. And I
suspect that one didn't do formatting.
For Qbus, it would be the RQDX, which was MSCP, and did both the RD
disks and RX50. I'm not sure, but I think the RQDX could perform some
sort of low level formatting for the RD anyway. Not sure what it would
say if you pointed it at the RX...
> I suppose you could on a Pro, since that had its own particularly disgusting junk controller. But I haven't seen RX50 formatting there. My impression was that they came factory formatted, with the DEC-specific 10 sector per track format.
Ugh! The PRO controller probably was weird enough to not allow you, even
though as far as I understand, it was also way more primitive than MSCP.
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