Fanuc A20B-2900-0293 ROM 256Kb Memory board. Normally this memory pcb interfaces between Fanuc NC and MC.
Running on 16/18 model A control systems. This board holds the ROM such as the system memory, ladder, and programs. The quarter meg A20B-2900-0293 ROM memory pcb is available @ DNC today, either as exchange or on an outright basis stock dependent with full testing and repair services available on the 16-A and 18-A control systems.