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What is this microPDP-11?
- Thread starter jplr
- Start date
pbirkel@gmail.com
Veteran Member
KDF11 is the 11/23 (F11 chipset). According to online documentation this was the least powerful configuration of the MicroPDP-11. An LSI-11 (KEV11 chipset; 11/03) would normally be in a BA11-M. Of course, a previous owner could have "downgraded" the MicroPDP-11 to an LSI-11 CPU. But not, AFAIK, DEC.
Look inside :-}.
Look inside :-}.
m_thompson
Veteran Member
Yes, look at the part number on the metal stiffener on the CPU to find out which model it is.
cchhrriiss11
Experienced Member
I got one of these MicroPDP-11 machines a little while ago as well, turned out to be an 11/23+ (KDF11-B)...
Anyone got a set of the CIS chips they want to sell???
-Chris
Anyone got a set of the CIS chips they want to sell???
-Chris
jplr
Experienced Member
Thanks all,
@cchhrriiss11, so if there is no indication of the model (apart 'MicroPDP-11'), it's a 11/23?
@cchhrriiss11, so if there is no indication of the model (apart 'MicroPDP-11'), it's a 11/23?
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cchhrriiss11
Experienced Member
Best way to tell is to open it up and see what CPU card is in it... there's always a chance it might have been upgraded in the past as well?
When I was researching mine on-line, it seems most of these "unlabelled" machines came as a 11/23 (non-plus) which is a dual-width card (as opposed to the quad-width 11/23+).
-Chris
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jplr
Experienced Member
Thanks Chris,
I have no access to the machine as it is ~900km (~600miles) away and the seller is reluctant to open the it or even to send it by a transporter. He asks prospective buyers to come and have a look.
Jean-Pierre
I have no access to the machine as it is ~900km (~600miles) away and the seller is reluctant to open the it or even to send it by a transporter. He asks prospective buyers to come and have a look.
Jean-Pierre
daver2
10k Member
In that case you assume it is the 'lowest cost machine' of that type for the purpose of pricing and negotiation. If you go and see on that basis, and it turns out to be a more expensive CPU that is fitted, it is a bonus for you...
Dave
Dave
Bitly
Experienced Member
I'd be nervous about buying something the seller won't open. It reeks of an empty card cage.
CW
Hunta
Experienced Member
I thought that they were not to be found at all now, but while I had the opportunity to buy on eBay, they appeared on sale twice. Once - only a microchip, once - a complete KDF11-B.
thunter0512
Veteran Member
What is so special about a Micro PDP-11?
jplr
Experienced Member
Thanks for all comments
If someone is interested it is this sale:
The seller has 13 microPDP: microPDP, microPDP-11/53, microPDP-11/73.
Some may work, but it's not for sure.
I have the impression he might sell each for ~$100.
As he does not want to tell much about their state nor send much photos, I am not sure they are in good condition.
This is probably because he does not know much about what it is, as he previously call them "IBM" which I presume is synonymous for him of "computer".
He wants people to "come and see", whatever that means.
It's in the East part of France, 250km/150 miles from Luxembourg/Stuttgart or Zurich. I am at 900km so it's too far for taking the risk of getting junk.
So if anyone is interested, please spare a chassis/PSU and backplane for me ;-)
If someone is interested it is this sale:
The seller has 13 microPDP: microPDP, microPDP-11/53, microPDP-11/73.
Some may work, but it's not for sure.
I have the impression he might sell each for ~$100.
As he does not want to tell much about their state nor send much photos, I am not sure they are in good condition.
This is probably because he does not know much about what it is, as he previously call them "IBM" which I presume is synonymous for him of "computer".
He wants people to "come and see", whatever that means.
It's in the East part of France, 250km/150 miles from Luxembourg/Stuttgart or Zurich. I am at 900km so it's too far for taking the risk of getting junk.
So if anyone is interested, please spare a chassis/PSU and backplane for me ;-)
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pbirkel@gmail.com
Veteran Member
And the sale price is $200-300 when they appear! Since it's double-wide (spans two sockets) supporting six dies I guess that's either $100-150 per "chip" or $33-50 per die :-}. But if you really want to run DIBOL fast ...
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jdreesen
Experienced Member
...interesting, as I will be shortly passing by very very close....Thanks for all comments
If someone is interested it is this sale:
The seller has 13 microPDP: microPDP, microPDP-11/53, microPDP-11/73.
Hunta
Experienced Member
I guess for COBOL.
For DIBOL there was "DIBOL instruction set" of commands - DIS - for LSI-11.
daver2
10k Member
It is a collection of 'stuff' - much smaller than the stash I gave away last year...
If you 'visit' you never know, you may pickup a bargain. But you could also pickup a lemon.
Dave
If you 'visit' you never know, you may pickup a bargain. But you could also pickup a lemon.
Dave
I believe I have a pair of them on 11/23+ boards. What would one do with them?I got one of these MicroPDP-11 machines a little while ago as well, turned out to be an 11/23+ (KDF11-B)...
Anyone got a set of the CIS chips they want to sell???
View attachment 1252729
-Chris
Also if I recall, Cobol81 can compile with the CIS option in the 11/23+, 11/24, or 11/44 systems.
cchhrriiss11
Experienced Member
pbirkel@gmail.com
Veteran Member
Generally speaking, string processing. The 11/44 implementation is well documented:
COBOL is specifically mentioned, but not DIBOL -- so my earlier comment was likely incorrect.
Hunta
Experienced Member
Not only string processing, but also decimal arithmetic