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A project log for HP 4952A turned general purpose CP/M machine

Attempting to reverse engineer an HP 4952A into a general purpose z80 computer capable of running CP/M.

trevor-johansen-aaseTrevor Johansen Aase 12/31/2018 at 22:350 Comments

On the bottom left we have all the CRT controls. The two AMD chips are presumably dual port RAM chips as the previous several 4951's all used this to eliminate any bus timing issues.

The DLC is not listed on the 4951C schematics but it has its on 32k RAM & ROM.

The Green chips are a z80 and PIO that connect to the pod pin-header. When removed the system still passes the self test so that weird. Apparently the "Remote" processor is the 8051 on the memory board. Maybe this is the capture streaming processor only and just relays data.

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