24 Jul
2003
24 Jul
'03
2:20 a.m.
Message: 39
Date: Wed, 23 Jul 2003 06:59:49
To: cctalk(a)classiccmp.org
From: Joe <rigdonj(a)cfl.rr.com>
Subject: Re: Data Systems Design DSD-880 8" floppy and hard drive?
Reply-To: cctech(a)classiccmp.org
At 10:19 PM 7/22/03 -0400, you wrote:
>>Bob Shannon wrote:
>
>> The DSD boxes I used do not emulate DEC drives, and made the 45 meg hard
>> drive
>> available as a single device.
>
>Jerome Fine replies:
>
>As far as I know, the DSD 880/8 and the DSD 880/30 all used
>only a Qbus controller. And they accepted the standard DEC
>device drivers in RT-11.
>
Ok, I can enhance this info somewhat.
I used both DSD 880 -8 and -30. (with great pleasure!)
They interfaced via a 26 pin flatcable to a host Adapter, and I had both
adapters for Q-bus and Unibus. Q-bus adapter was 22-bit.
(in fact, we used a 25 pole data-switch in this flat-cable to switch this
storage-system between 2 machines, as desired)
I used this storage subsystem under RSX11-M with standard drivers, DSD provided
a utility diskette with some handouts about RSX and RT and some driver-patches
(eg for 8-meg extended RL01, or RX03) that I never used. Should have this disk
still sopmewhere. Any interest?
If it is an DSD880 for pdp11, then the emulation is RX / RL. If it is emulating
MSCP its probably the DSD 9xx series of devices.
DSD440 is a dual 8" floppy, in 5" enclosure (Half RX02-formfactor!)
and providing RX01, -02, -03 emulation for all DEC OS's of those days.
I remember there were also adapters for other architectures / busses, DSD did
not limit the 440 or 880 to DEC-machines.
There may have
been other DSD boxes in addition the the DSD 880
and DSD 440, but I had not heard about them, let alone the details.
FWIW I was looking through my Intel docs last night and found a manual
for a DSD Multibus hard drive controller.