I have was appears to be a memory board made by "EMM". It also appears to be Q-bus, at least the power and ground seem to be in the right places to be Q-bus. Anyway, the board has 64 of these chips, and looking at the interconnection between chips, they appear to be arranged in 2 groups of 32. The chips are labeled: SEMI 4200ACC 7733 These are 22 pin chips, made in 1977, but I can't seem to find any chip manufacturer named SEMI or any reference to this 4200 number. Can anyone identify these chip?