Data Systems Design DSD-880 8" floppy and hard drive?

From: Bob Shannon <bshannon_at_tiac.net>
Date: Tue Jul 22 19:07:00 2003

Jerome H. Fine wrote:

>>Bob Shannon wrote:
>>
>
>>RT-11, the DSD boxes cannot use stock DEC drivers.
>>
>
>Jerome Fine replies:
>
>I believe you are incorrect. The extra detail is as follows:
>
>The DSD boxes can use BOTH the hard drive (emulating
>an RL01 for the 8 MByte hard drive or 3 * RL02 for
>the 30 MByte hard drive) and the single 8" floppy drive
>(emulating an RX02) with stock (distributed) device
>drivers. I have done so with BOTH V4.00 and V5.03
>distributions of RT-11.
>

The DSD boxes I used do not emulate DEC drives, and made the 45 meg hard
drive
available as a single device.

I have, err, well, Jay West has a DSD floppy-only (RX-02) emulation in
his 11/34a out
in my garage, and that does use the standard driver.

I guess DSD had many varients, and we must be talking about different
products.

But the unibus version of the DSD interface for the floppy-hard drive
combo's I've
worked with all needed a DSD driver for RT-11.

I ~think~ the DSD driver exists, on a LINC tape (Jay's got a Computer
Operations LINC
tape drive, which also uses a non-standard driver). For some time, that
machine could not
be upgraded to a newer version of RT-11 because the LINC tape driver
would not assemble
correctly under the newer version (I cannot, for the life of me recall
which versions these were!).

Something about an interrupt function call....sorry, its been too long,
and I've forgotten the
details. Anyway, all the 'funky' drivers and their source was saved on
a LINC tape, which I loved
using more than the newer version of RT-11.

That 11/34a system has accumulated a strange set of peripherals saved
from the decommissioning
of a long series of very choice Unibus hardware, starting with a DEC
Graphic 11/40, then an 11/T55, and
an 11/60. I got rid of all of that, keeping only an 11/35 and the 11/34
due to size. Now only the 11/34
remains, and thats Jay's.

Maybe once Jay actually gets this stuff, and gets it all put together,
he will find a stack of odd drivers and
their soruce code on one of the LINC tapes?
Received on Tue Jul 22 2003 - 19:07:00 BST