17 comments
the array is 32x32, and there seem to be four outputs at the bottom of the array. that would make this a 256x4 ROM. pin 9 (and a bunch of others) are inputs. they go through a series resistor, a diode clamp (not visible here) and into a double set of inverters. this creates a buffered version of the input and an inverted version. looks like a perfect match to the MCM14524! unfortunately it is a mask ROM: "This device is ordered as a factory special with its unique pattern specified by the user." @tubetime I think Fujitsu (or maybe it was Toshiba?) was later accepting 8mm backup tapes. Handy for the bigger ROMs |
there's something weird about the markings on the bottom of the chip