SMS LE interface

Doc Shipley doc at
Sat Nov 25 21:04:27 CST 2006

Ethan Dicks wrote:
> On 11/25/06, Brad Parker <brad at> wrote:
>> The one I have has a boot prom; I don't know if it's rx01/02 compatible.
> I can't guarantee your model (mine is a dual floppy), but AFAIK, all
> of the SMS drives for DEC machines are at least RX01, if not RX02,
> compatible. Moreover, most, if not all, of the SMS drives should be
> able to take a totally blank floppy and format it (DEC RX01s can't
> format a thing, and the RX02 can only re-write the data portion of the
> track of a pre-formatted RX01 disk and make that part double-density,
> thus, converting an RX01-K into an RX02-K).
> There are other ways of starting with blank floppies (the RX01 format
> is large-system IBM compatible, thus standard), but few options using
> a DEC CPU.

   I have a Unibus SMS board marked FD1100I on a hand-lettered label, 
and SMS PE-HIP with an Intel 8008 and a Shugart FDC chip.  I don't 
remember which one.

   I'd love to know how to use it.  That Shugart chip implies it has a 
lot more smarts than an RX02 controller.  If it does Winchester too, so 
much the better.


   There are a 50-pin, a 40-pin, and a 30-pin header on it.  I can scan 
it Tuesday for a hi-res image if anyone's interested.

   Err.  I *assume* it's Unibus.  It came in a non-functional PDP-11/04.


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