2 Oct
2009
2 Oct
'09
2:28 p.m.
Does anyone have a PDP 14? Or has anyone ever seen
one out in the "wild"?
If so, please contact me directly ;)
The PDP-14 was not a conventional computer... it was what we call today a PLC
(programmable logic controller). Very adaptable to ladder logic and a bit more.
DEC was pretty swift in how they allowed the PDP-14 to be configured via a real computer
(a -11 or -8). It wasn't the GUI of PLC configuration today or even of the 80's,
but it was a good start.
The overall model of PLC configured or monitored by a computer still holds true today, I
think that DEC could have really taken this idea and run with it but the overlap between
industrial control and computers even today is less than thorough. The computer geeks
don't understand the industrial control and process engineers for the most part (thus
the common misuse of Windows PC's where a PLC could do the job far better and without
point-and-drool.)
IMHO if you are interested in PDP-14 you must also be interested in early Modicon
PLC's, which were far more common, predate the PDP-14, used core memory like the
PDP-14, and which the PDP-14 was pretty much a clone of. I think Modicon was also a
Massachusets company like DEC.
I never used a PDP-14 but I always understood them to be very much like the core-based
Modicons I used.
Tim.
2 Oct
2 Oct
4:33 p.m.
On 2 Oct 2009 at 9:28, Shoppa, Tim wrote:
IMHO if you are interested in PDP-14 you must also be
interested in
early Modicon PLC's, which were far more common, predate the PDP-14,
used core memory like the PDP-14, and which the PDP-14 was pretty much
a clone of. I think Modicon was also a Massachusets company like DEC.
Do any IBM 1710s survive? That certainly has to qualify as one of
the earliest process-control computers around.
--Chuck
11:04 p.m.
I have never seen one alive, but I have the remains of one: logic unit
boards, miscellaneous generic flip-chips, some I/O boards, etc.
Unfortunately, no backplane. This was the original PDP-14
(Straight-14?). It was to have a core-rope ROM in the final installation
vs. core. I think there were later versions that had writable program
storage.
Shoppa, Tim wrote:
The PDP-14 was not a conventional computer... it was
what we call today a PLC
(programmable logic controller). Very adaptable to ladder logic and a bit more.
Very primitive, but the right thing for discrete logic control.
I have some notes about it here: http://www.chdickman.com/pdp14/
I think Motorola had a 16pin dip logic unit that did basically the same
thing.
DEC was pretty swift in how they allowed the PDP-14 to
be configured via a real computer (a -11 or -8). It wasn't the GUI of PLC
configuration today or even of the 80's, but it was a good start.
The parts I have came from a system that was to have run a stamping
press. In this case, the PDP-14 was basically a discrete I/O adapter for
a PDP-8/e.
The overall model of PLC configured or monitored by a
computer still holds true today, I think that DEC could have really taken this idea and
run with it but the overlap between industrial control and computers even today is less
than thorough. The computer geeks don't understand the industrial control and process
engineers for the most part (thus the common misuse of Windows PC's where a PLC could
do the job far better and without point-and-drool.)
PLCs to control the process and PCs to monitor the process. I don't know
that I want Vista in charge. It might be only a tool, but that tool
might be very expensive.
IMHO if you are interested in PDP-14 you must also be
interested in early Modicon PLC's, which were far more common, predate the PDP-14,
used core memory like the PDP-14, and which the PDP-14 was pretty much a clone of. I think
Modicon was also a Massachusets company like DEC.
The cool thing about MODICON is that a simple protocol that they devised
has been widely implemented. It has become a least common denominator
language for communication between devices and controllers.
-chuck
5 Oct
5 Oct
1:14 a.m.
I worked on one or two in the field back in the '70's, but don't remember
very much about system configurations. I don't remmember anything about the
main box.
I have a VT14 terminal, 14/30's, 14/35's, ICR11, ICR8, ICS11, ICS8, some in
quantity. I also have a large quantity of H1600's, H1500's, H1550's,
H1650's
and their corresponding distributuion panels. I'm taking these numbers from
memory so the numbers might be a little off and this list is by no means
complete. The documentation for most items is here and I offered it to Al
to scan a few years ago, but he has probably forgoten about it now.
If anyone has working knowledge of this equipment, please feel free to
contact me.
On Fri, Oct 2, 2009 at 5:04 PM, Charles H Dickman <chd_1 at nktelco.net> wrote:
I have never seen one alive, but I have the remains of
one: logic unit
boards, miscellaneous generic flip-chips, some I/O boards, etc.
Unfortunately, no backplane. This was the original PDP-14 (Straight-14?). It
was to have a core-rope ROM in the final installation vs. core. I think
there were later versions that had writable program storage.
Shoppa, Tim wrote:
The PDP-14 was not a conventional computer... it
was what we call today a
PLC
(programmable logic controller). Very adaptable to ladder logic and a bit
more.
Very primitive, but the right thing for discrete logic control.
I have some notes about it here: http://www.chdickman.com/pdp14/
I think Motorola had a 16pin dip logic unit that did basically the same
thing.
DEC was pretty swift in how they allowed the
PDP-14 to be configured via a
real computer (a -11 or -8). It wasn't the GUI of PLC configuration today or
even of the 80's, but it was a good start.
The parts I have came from a system that was to have run a stamping press.
In this case, the PDP-14 was basically a discrete I/O adapter for a PDP-8/e.
The overall model of PLC configured or monitored
by a computer still holds
true today, I think that DEC could have really taken this idea and run with
it but the overlap between industrial control and computers even today is
less than thorough. The computer geeks don't understand the industrial
control and process engineers for the most part (thus the common misuse of
Windows PC's where a PLC could do the job far better and without
point-and-drool.)
PLCs to control the process and PCs to monitor the process. I don't know
that I want Vista in charge. It might be only a tool, but that tool might be
very expensive.
IMHO if you are interested in PDP-14 you must
also be interested in early
Modicon PLC's, which were far more common, predate the PDP-14, used core
memory like the PDP-14, and which the PDP-14 was pretty much a clone of. I
think Modicon was also a Massachusets company like DEC.
The cool thing about MODICON is that a simple protocol that they devised
has been widely implemented. It has become a least common denominator
language for communication between devices and controllers.
-chuck
9:05 a.m.
Paul Anderson wrote:
I worked on one or two in the field back in the
'70's, but don't remember
very much about system configurations. I don't remmember anything about the
main box.
I have a VT14 terminal, 14/30's, 14/35's, ICR11, ICR8, ICS11, ICS8, some in
quantity. I also have a large quantity of H1600's, H1500's, H1550's,
H1650's
and their corresponding distributuion panels. I'm taking these numbers from
memory so the numbers might be a little off and this list is by no means
complete. The documentation for most items is here and I offered it to Al
to scan a few years ago, but he has probably forgoten about it now.
yup.. I dug up some information out of the DEC archive at CHM which I put up
on bitsavers.
If anyone has working knowledge of this equipment,
please feel free to
contact me.
The company I worked for supported 14/30's in the Pabst brewhouse. The main
box was downloaded from a high speed serial link from the VT14. It was possible
to do ladder-logic development under OS/8 with some software my boss wrote.
Internally, the 14/30 was built like an 8/E, even used the 8's memory assy.
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participants (5)
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aek＠bitsavers.org -
cclist＠sydex.com -
chd_1＠nktelco.net -
tshoppa＠wmata.com -
useddec＠gmail.com