ISO: Motorola MDP-1000 info/software

[Josh Dersch]

On Wed, Sep 30, 2020 at 5:20 AM ED SHARPE via cctalk <cctalk at classiccmp.org>
wrote:

> whats  the  story on  this...i  see  items   but no pix. also   check
> your  spelling on Motorola; Instrmentation and Control, Inc.  that  is  in
> the  index. let me  now  if  there  is a photo  group  for this at  least
> with the  covers   I always  wondered if it  was  just  a  12 bit  computer
> or  if it  was   software  compatible  with pdp-8? I wonder  what  else
> this  division of Motorola produced....   there  was a  teleprinter   they
> made...   Here is  the link  to the  teleprinter  it  is  filed under gov
> div. http://www.smecc.org/motolola_government.htmi  think i got the  12
> bit  computer manual  from same person.


The link is dead (seems misspelled, but even correcting it (and changing
htmi to html) doesn't result in a link that works).  I can't find any
reference to you posting a link to the manual in the cctalk archives, but
that doesn't mean it isn't there, somewhere.  If you're able to scan this
manual, I'd love a copy.

The MDP-1000 is in no way like a PDP-8.  Different memory word-size, has an
actual ALU, 5 registers, etc.  It's a very odd little system.  I was doing
a bit more reading last night and while the ALU is 12 bits wide, the Link
(carry) bit is the carry out from bit 7.  Logical operations only operate
on the low 8 bits, though there are variants that work on the upper 4 bits
only, as well.

- Josh