Wire Wrapper needed for PDP-7

From: Tore S Bekkedal <toresbe_at_ifi.uio.no>
Date: Mon Feb 9 13:57:27 2004

>If I understand you correctly, you are saying that major subsystems were
>added to the CPU and wired into the backplane by a former user, who removed
>these components without regard to its effect on the operability of the
>machine before you came into possession of it. That wouldn't surprise me at
>all. Many academic and lab shops did extensive custom modifications, like
>the famous BBN paging box on the Tenex KA-10s.

No, the Oregon PDP is also barely recognizeable. The PDP-7 was originally
meant to be scrapped (was laying around) but it was salvaged by Professor
Nordhagen, and ccmaniac librarian Knut Hegna (who has some other minis
next to the PDP-7) when the new library building was built in 1987.

The last trace of usage I have is 1976.

>These machines went through multiple
>revisions and field ECOs during their lifetime. There was a set of field
>maintenance prints issued for the specific revision that a customer had,
>which was then kept up to date with the machine. (At least this is true of
>the Straight-8 of similar vintage.)

I have three sets of wrap lists. My intention (bad idea?) was to wrap
an original PDP-7/A, instead of one with ECOs - and later apply
any crucial ECOs I came across. (Al, do you have any?)

I could probably cook up some program that would give me schedules
based on wire lists (if I am understanding the concept of 'schedule' correctly
as something describing the order in which the wires are to be wrapped)

The PDP-7 ended up with several ADC's, apparently it had a plotter,
an IPB, a 'poor man's API', and so on. Some EE students aparently
kept it alive during its last days, but gave up, and returned it to the
Good Professor which originally bought it, and let me work on it.
He put it in storage, and it's now an exhibit.

Funny how PDP-7's tend to turn up vacantly sitting in corners, isn't it...? :)

>I can't read a word of Norwegian, but from the pictures, it appears that
>Norsk Data
>made quite a number of interesting machines from 1967 into recent years.

Yes, it was a fairly successful machine. I've heard that the first WWW server at
CERN actually was an ND machine, which wouldn't surprise me, given
the close cooperation the two institutions enjoyed. (I've heard.)

I was yesterday at the Norwegian museum of technology, (I may be working
with them on another restoration project - IBM 360/370-ish - but that is
entirely in the future and no deals have been made yet - if this is happening,
I will of course post immediately to cctech ;)) and amongst some neat exhibits
(Jaquard loom, IBM 650 (You should have seen me - crawling down, looking
at interiors and drum)) I saw a NORD-1. I don't know much about the machine,
but I do know that the one 7 was hooked up to had three 9-tracks, 16k core, but
not a very good display - the PDP-7 was later used as something of an intelligent
terminal and data-gatherer, hooked up to some (apparently brilliant) Italian ADCs,
and letting the NORD-1 do the numbercrunching.

The NORD-1 used IC's, and came with a line printer, that's about all I know. I do
seem to remember a 16-bit word length, though. The NORD-1 was a commercially
successful machine, and earned ND quite a lot of money. I believe it was the
NORD-100 which really got ND off to a start - but that's from doubleplusvague
memory. I'll get around to translating that page :)

Back to the wire-wrapping thing: Is it really that bad? There are admittedly a lot
of wires on it, but it doesn't seem all too hard (especially with an electric wrapper!)
Am I wrong, and am I not weighing the effort correctly? Is it harder than soldering?
The pins are not small, they are about 2mm x 1mm from memory measurement.
I thank everyone offering me wrappers!


Thanks for all your help, people :)

Received on Mon Feb 09 2004 - 13:57:27 GMT

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