24 Oct
2017
24 Oct
'17
12:42 p.m.
-----Original Message-----
From: cctalk [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Dave Wade
via cctalk
Sent: 24 October 2017 10:01
To: 'Kip Koon' <computerdoc at sc.rr.com>; 'General Discussion:
On-Topic and
Off-Topic Posts' <cctalk at classiccmp.org>
Subject: RE: Which Dec Emulation is the MOST useful and Versatile?
Kip,
It depends on what your interest is! Of course PDP stood for "Programmed
Data Processor"
https://en.wikipedia.org/wiki/Programmed_Data_Processor
and avoids the use of the word computer because the backers of Digital did
not
want them building a Computer. I believed it also
helped sales as it
by-passed
corporate purchasing edicts which said only central IT
departments could
buy
computers...
The PDP8 is the smallest but most hackable, but things like Oscars 8I or
the
SBC6120 which turns up from time to time (google
SBC6120) mean that its
possible to have something approaching a physical PDP-8 to play with
rather
than just emulation. But if small is beautiful then
may be the machine for
you.
These were used all over the place. Manchester
University Medical School
had
one connected to its IBM7090, Leeds to its KDF9.
Really a revolution in
computing. Its amazing what folks got to run on these using only paper
tape.
Eventually made in a Microprocessor with the Harris
and Interrail 6100 and
then the Harris HD6120..
The PDP-11 covers a huge range of systems and I know there are still some
PDP-11's in service. At one time Barclays, a UK bank used them as Branch
Controllers so every branch had a PDP-11 and in those days there were many
more branches than there are now. I learnt BASIC on one at Salford
University
in 1977. When I worked for the uk's Natural
Environment Research Council
we
must have had hundreds of the things. We used them to
build "media
conversion" systems that would copy data from scientific instruments and
to
build front end concentrators for our Honeywell L66.
More capable than the
PDP-11 but possibly less easy to hack. Lots of different Operating Systems
out
there but for some licensing is interesting. Was used
to develop early
Unix
The VAX-11 is probably my favourite box. I have several physical VAXen
all
with the VMS OS installed. Really gives a flavour of
what interactive
computing
was like in the 1970's and 1980's. Very
capable but even less easy to
hack, and
initially big and expensive, which is why the PDP-11
continued to be
available
for many years.
There is also the PDP-10/Dec System 10 which was claimed to be a
Mainframe
but I never met one of these. Probably not for the
faint hearted.
Ah the PDP10! Although the very first computer I used was a PDP11, it was so
briefly that I really consider the PDP10 (in DECSYSTEM-20 form) to be my
first computer. It is easy to emulate in SIMH, although the SIMH emulation
is of a less capable processor (KS10) and I think KLH10 is the best emulator
for that (but I have never used it).
For general DEC goodness I would go for a PDP11 or a VAX, preferably both.
And as Dave and others have pointed out, PDP was not really a line of
computers, it was multiple lines of different computers.
I forsee a *long* thread here.
Regards
Rob