4 Apr
2013
4 Apr
'13
11:31 p.m.
Hah, a thread just in time for me!
Hello fellow collectors.
I got the card-less carcass of a pdp-11/23 (says so on the front and back type labels)
some weeks ago.
This is going to be my first pdp ever so please be a bit patient with me :)
It is the BA11 variety and contains a H9273 backplane, which as far as I could find out is
QQ-CD
(consistent with your statement below).
However the backplane has a sticker on it which is stamped "11/03" (?!)
So what kind of CPU (or more generally, kinds of boards) am I looking for to populate this
puppy?
I've already done some reading on DEC stuff from bitsavers and gleaned that in order
to make it an
11/23, it would have to hold either an M8186 (KDF11-A) or an M8189 (KDF11-B) processor.
As the M8186 only comes in a dual slot form factor, it clearly can't make use of the
CD
interconnect on the backplane. The M8189 is a quad-width board, but with the CD part
configured
for a serpentine backplane (the manual mentions two jumpers to be removed when using in
another
environment to avoid shorting signals together), so again no "meaningful" use of
the CD lanes.
What are these intended for anyway (I was thinking of some sort of PMI predecessor,
probably
wrong by now), and what boards do I need to take advantage of them in this machine?
Also, are there any ressources online about the Q-22 upgrade? I might need do do that
because I
already was promised a 512kw MOS memory board by another German collector.
TIA, yours sincerely
Arno
Pete Turnbull <pete at dunnington.plus.com> wrote:
Indeed, or as Jerome suggested, looking at the configuration of the
cards may give you a clue. So would the type of box: if it's a 3U-high
(5.25") grey-fronted-metal-panel rack-mount box with three toggle
switches, it's a BA11-N or BA11-S, which have straight backplanes (and
are all QQ-CD), if it's a small tabletop box or a 2U (3.5") it's a
BA11-V (tabletop) or BA11-M (2U) which have serpentine backplanes, and
if it's a floor-standing microPDP-11 (or microVAX) box or a chassis with
four or six pushbuttons on the front, it's a BA23 box which is QQ-CD in
the top slots and serpentine below.
Or count the card slots. All 9-slot backplanes are straight. 8-slot
and 13-slot are mixed (for microPDP-11 and microVAX). Anything else is
serpentine.
BA11-M and BA11-V boxes are relatively uncommon. If it's a BA11-N,
although the backplane is 18-bit, it's very easy to upgrade to 22-bit.
> -- which I understand can be serpentine,
All Q-Q backplanes are serpentine, and all straight backplanes are
QQ-CD. The only odd one is the hex-high DDV11-B, which is a serpentine
backplane in the ABCD positions and not bussed at all (except for power
in the standard contact positions) in EF - it's meant for custom wiring.
Of course we're assuming it's a DEC box with a DEC backplane. A
Plessey backplane, for example, might be different, but you'd probably
know if it was non-DEC, because it's pretty rare to find DEC's dark
green connectors on anything non-DEC. Plessey and GEC ones, again for
example, are white.
--
Pete Peter Turnbull
Network Manager
University of York
5 Apr
5 Apr
5:42 a.m.
On 04/05/2013 02:31 AM, Arno Kletzander wrote:
Hah, a thread just in time for me!
Hello fellow collectors.
I got the card-less carcass of a pdp-11/23 (says so on the front and back type labels)
some weeks ago.
This is going to be my first pdp ever so please be a bit patient with me :)
It is the BA11 variety and contains a H9273 backplane, which as far as I could find out
is QQ-CD
(consistent with your statement below).
However the backplane has a sticker on it which is stamped "11/03" (?!)
Look uo the backplan to find out its configuration.
So what kind of CPU (or more generally, kinds of boards) am I looking for to populate
this puppy?
I've already done some reading on DEC stuff from bitsavers and gleaned that in order
to make it an
11/23, it would have to hold either an M8186 (KDF11-A) or an M8189 (KDF11-B) processor.
Also read the fine manual for the quad width 11/23 you will find there
are jumpers/switches for
use in AB/CD backplanes. Most quad width cards also conform to that.
As the M8186 only comes in a dual slot form factor, it
clearly can't make use of the CD
interconnect on the backplane. The M8189 is a quad-width board, but with the CD part
configured
for a serpentine backplane (the manual mentions two jumpers to be removed when using in
another
environment to avoid shorting signals together), so again no "meaningful" use
of the CD lanes.
CD lines are needed for RL11 controller (two board RL01/02
controller).
What are these intended for anyway (I was thinking of
some sort of PMI predecessor, probably
wrong by now), and what boards do I need to take advantage of them in this machine?
Also, are there any ressources online about the Q-22 upgrade? I might need do do that
because I
already was promised a 512kw MOS memory board by another German collector.
And if all else fails you can replace the backplane with one that is
AB/AB as I've done that many times.
Allison
TIA, yours sincerely
Arno
Pete Turnbull <pete at dunnington.plus.com> wrote:
Indeed, or as Jerome suggested, looking at the configuration of the
cards may give you a clue. So would the type of box: if it's a 3U-high
(5.25") grey-fronted-metal-panel rack-mount box with three toggle
switches, it's a BA11-N or BA11-S, which have straight backplanes (and
are all QQ-CD), if it's a small tabletop box or a 2U (3.5") it's a
BA11-V (tabletop) or BA11-M (2U) which have serpentine backplanes, and
if it's a floor-standing microPDP-11 (or microVAX) box or a chassis with
four or six pushbuttons on the front, it's a BA23 box which is QQ-CD in
the top slots and serpentine below.
Or count the card slots. All 9-slot backplanes are straight. 8-slot
and 13-slot are mixed (for microPDP-11 and microVAX). Anything else is
serpentine.
BA11-M and BA11-V boxes are relatively uncommon. If it's a BA11-N,
although the backplane is 18-bit, it's very easy to upgrade to 22-bit.
> -- which I understand can be serpentine,
All Q-Q backplanes are serpentine, and all straight backplanes are
QQ-CD. The only odd one is the hex-high DDV11-B, which is a serpentine
backplane in the ABCD positions and not bussed at all (except for power
in the standard contact positions) in EF - it's meant for custom wiring.
Of course we're assuming it's a DEC box with a DEC backplane. A
Plessey backplane, for example, might be different, but you'd probably
know if it was non-DEC, because it's pretty rare to find DEC's dark
green connectors on anything non-DEC. Plessey and GEC ones, again for
example, are white.
6:01 p.m.
New subject: pdp-11/23 config
The loos of the *physical* media is not so much troubling as is the loss
of web content. As companies go out of business the content evaporates.
The Wayback Machine helps a bit, bot think of all of the ftp content
(which isn't preserved by archive.org) that has just plain evaporated.
I would guess that the volume of this might even be larger now than the
stuff archived on old magtape.
Of all the bookmarks I have in my browser accumulated over the last 7 or
8 years, at least half of them are dead links.
--Chuck
11:33 p.m.
New subject: pdp-11/23 config
------ Original Message ------
From: "Chuck Guzis" <cclist at sydex.com>
To: "General Discussion: On-Topic and Off-Topic Posts"
<cctalk at classiccmp.org>
Sent: 06/04/2013 02:01:04
Subject: Re: pdp-11/23 config
The loos of the *physical* media is not so much
troubling as is the
loss of web content. As companies go out of business the content
evaporates. The Wayback Machine helps a bit, bot think of all of the
ftp content (which isn't preserved by archive.org) that has just plain
evaporated.
I note from the BBC News that UK Libraries and Museums are to start
archiving web content:-
http://www.bbc.co.uk/news/entertainment-arts-22028738
I would guess that the volume of this might even be larger now than the
stuff archived on old magtape.
Of all the bookmarks I have in my browser accumulated over the last 7
or 8 years, at least half of them are dead links.
--Chuck
Dave
G4UGM
5:46 a.m.
On Apr 5, 2013, at 2:31, "Arno Kletzander" <Arno_1983 at gmx.de> wrote:
Hah, a thread just in time for me!
Hello fellow collectors.
I got the card-less carcass of a pdp-11/23 (says so on the front and back type labels)
some weeks ago.
This is going to be my first pdp ever so please be a bit patient with me :)
It is the BA11 variety and contains a H9273 backplane, which as far as I could find out
is QQ-CD
(consistent with your statement below).
However the backplane has a sticker on it which is stamped "11/03" (?!)
So what kind of CPU (or more generally, kinds of boards) am I looking for to populate
this puppy?
I've already done some reading on DEC stuff from bitsavers and gleaned that in order
to make it an
11/23, it would have to hold either an M8186 (KDF11-A) or an M8189 (KDF11-B) processor.
The H9273 is perfectly compatible with an 11/23 CPU; there
is a jumper you can set for 18-bit use. Obviously, though,
turning it into a 22-bit backplane is preferable.
Fortunately, that's pretty easy.
As the M8186 only comes in a dual slot form factor, it
clearly can't make use of the CD
interconnect on the backplane. The M8189 is a quad-width board, but with the CD part
configured
for a serpentine backplane (the manual mentions two jumpers to be removed when using in
another
environment to avoid shorting signals together), so again no "meaningful" use
of the CD lanes.
Correct. The Qbus PDP-11s only used the CD lane for PMI
(or custom logic, if you had that). I'd get the M8189 if you
can, because it saves you the hassle of finding boot ROM
and serial cards for the console.
What are these intended for anyway (I was thinking of
some sort of PMI predecessor, probably
wrong by now), and what boards do I need to take advantage of them in this machine?
For an 11/23, those lanes will just go unused. It's not
so bad, really; you have to try pretty hard to fill up 9
slots.
Also, are there any ressources online about the Q-22
upgrade? I might need do do that because I
already was promised a 512kw MOS memory board by another German collector.
The 11/23 processor manual will tell you which pins
are BDAL18:21. You just need to bus those together.
The H9273 doesn't have wire wrap stakes out the back,
so you'll have to solder, but it's not very hard at all. If it's in
a box labelled 11/23, though, check to make sure someone
hasn't already performed the modification.
- Dave
4284
days inactive
4285
days old
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participants (5)
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ajp166＠verizon.net -
Arno_1983＠gmx.de -
cclist＠sydex.com -
dave.g4ugm＠gmail.com -
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