That might a tough one to replace, if you cannot find the original. It is a 16-pin package, and no one makes this package anymore. It is a bipolar PROM, and it is a 4-bit PROM which makes this even more of a challenge. The pinout is equivalent to an Intersil IM5623 or Fujitsu MB7052. I played around with this awhile back, which is why it is still fresh in my head. None of the programmers I had read this chip. I had to hodge-podge an adapter to read it. But reading it is only half the battle.
This PROM doesn't actually contain code. Instead, it contains a truth table, as it acts like a PAL or GAL. We call it a "combinational logic" PROM, and in this particular case it is used to address the DRAM. Even if you have the binary file for it, you need to get something like a 2716, along with an adapter, so that it can fit into the 16-pin socket on the motherboard. There are some people who sell adapters for this very purpose. The people who usually do this sort of thing are 8-bit arcade game enthusiasts.
