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Anyone got a set of 80s Fujitsu databooks?

Wide DIP. If it was a mask ROM, I'd expect other identification. I've got two of them on a board and other than the Fujitsu logo, part number and date code (83), there's nothing.
I've run into Fujitsu IC parts before--the numbering system is purely unique. For example, consider the Fujitsu MB8877 - a +5 volt pin-compatible clone of the WD1793. I've also got a bunch of TTL logic like that--they're 74LS parts, but Fujitsu numbering.
 
Took a look at the PCB. The MB14275 is paired with an MB14276 and there is a small bit of labeling--one has 00 and the other has 08.
Looks like a mask-programmed ROM. Damn.
 
I checked all the books on Archive.org and Bitsavers and its not listed in any... Think you are stuck contacting them. 14xxx series is microprocessor family/ttl logic.
 
Oh, I did those checks before posting here and even checked some of the Chinese chip sellers. No dice. So they're ROMs and I don't have a clue what the original contents were.
 
I checked all the books on Archive.org and Bitsavers and its not listed in any... Think you are stuck contacting them. 14xxx series is microprocessor family/ttl logic.

It isn't because I haven't been trying. Fujitsu data books are particularly difficult to find.
 
No kidding. I have some Fujitsu ICs that I picked up in the 80s and can either find no mention at all, or just a passing mention. For example, I've got a couple of what appear to be hybrid CRT controllers; sort of a PGA in a can. I have part numbers, but no datasheets.
 
Out of curiosity, what are these mysterious chips from? If they are (probably) ROMs have you tried reading them, or is it obvious that the magic smoke escaped?
 
Just feeling one of them running very hot tells me that they're not right--and, of course, the function isn't there. I suppose that I could try to read them, but I'm not sure what that would get me. Oh--paper tape reader.
 
I just bought a paper tape reader with these same chips (MB14275 and MB14276) - haven't powered it up yet, I'll try to dump the roms before I do.
 
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No hurry--I may have succeeded in getting mine to sit up and perform--could have been a problem in a misplaced PSU ground (note that the +5 and +24 supply lines have independent ground returns; you need to tie the pins on the edge connector is powering from a common-ground power supply).
At any rate, I've got to cut some firmware and do a little carpentry before I'm ready to proceed.
 
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At first glance they don't look like normal ROMS. On the 14276 pins 19-23 are pulled high and pins 1-11 are connected directly to pins 13-23 of the 14275. Also, the only other chips are a handful of discrete logic.
 
Yup, it's a puzzle. The later readers (IIRC 2702) used conventional MPU logic.
Could it be that the two chips constitute an MCU? Without even a schematic, it's a guessing game.
 
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