Computermuseum der Fakultät Informatik deutsch français
CPU card In principle, this is the ALU with the register file. Except for two black 28 pin ICs (64x9 bit TTL RAM) at the middle top, everything is IBM custom. And also for the other DIL TTL ICs you need a list in order to decipher what function they contain. That's because - of course - IBM also labelled standard ICs from other manufacturers with a proprietary number.