What is this? IBM 3422

[rmay635703]

 

[Al Kossow]

where did you come up with "3422" ????

it's probably a board out of a 3174, judging by IC date codes, made in 1988

boards have a 7 digit part number, this one's is 6147566

web searches for IBM board numbers is collossally awful

 

[rmay635703]

Thanks

It was a random number on the board, I used to have a dozen random boards like this some populated with lots of silver cans, they came with a bunch of AT style motherboard scrap
this one managed to miss my last recycling run as I never knew what purpose these served.

 

[Al Kossow]

it's unfortunate they were ecycled. there are hobbyists now interested in late 80's IBM non-PC equipment

 

[rmay635703]

it's unfortunate they were ecycled. there are hobbyists now interested in late 80's IBM non-PC equipment

I tried to get folks interested but given I didn’t know what they were no one seemed to be interested at the time.

 

[Al Kossow]

I've been doing a lot of IBM documentation scanning from that era because so little was generally known about their products in the hobby community.
Now there's a small but growing community of people hacking on 80s IBM comms and midrange equipment.

 

[g4ugm]

I don't think its out of a 3174. I own a couple and there is is nothing like that in any of them. However similar boards are found in lots of other IBM equipment from tape drives, disk drives down to the Selectric Electronic Composer...

 

[Al Kossow]

I really need to create a directory of IBM board pictures and part numbers on bitsavers.
They moved away from the old 360-era block connectors in their products around then.

 

[Chuck(G)]

The stopper for a lot of people is IBM-unique labeling and parts. I can clearly see Intel, Hitachi, Mitsubishi, Motorola and TI logos on the ICs on that board, but they're all house-numbered. And what do you do about the IBM silver-can hybrid circuits?

You can make some guesses--the Intel 40 pin DIP might be an 8085 with SRAM off to the right of it. But that would only be a guess--it could also be an 8051 or some custom design.

 

[Al Kossow]

An IBM to jelly bean list exists.
I don't know if anyone else has been expanding it.

http://bitsavers.org/pdf/ibm/logic/IBM_Part_Number_to_Industry_Part_Number.txt

IBM was like AMP with their "7 digit number could be anything" numbering scheme, then they went to
nnxnnnn alphanumeric numbering

the really frustrating thing is they don't put board part numbers on their engineering drawings

I've been trying to add that information to the FE information that I've been accumulating

Also, no one had been photographing the insides or the boards of their equipment.
Like I said, not a lot of hobbyist interest in anything bigger than PCs until recently.

 

[Chuck(G)]

4178615 8085 MICROPROCESSOR

The XCO adjacent to it is tagged with 6.144Mhz, so the 8085 is running at 3.072MHz, which is a convenient number if you're doing serial protocols. But that could be coincidental.

So my guess was right there--but the rest of the large DIPs don't appear in the list.
Yet, all of these had to be procured via a detailed specification. I wonder where that documentation wound up?

 

[recoleta]

Found a blister full of tin can IBM 3422 chips here in Córdoba, Argentina.
They belonged to a Lab in the UTN-FRC.