HP-85 Port Extender?


The HP-85 has 4 expansion ports, but I would need 5. Does anybody know if there is a possibility to connect more than 4 expansion modules to the HP-85 (perhaps something like the HP-41 port extenders)? Or is it possible to connect the 16K memory module to the internal hardware (i.e. not using an expansion slot)? Any ideas highly appreciated :-)

Juergen (CH)


Yes, I have an HP-85A in which the previous owner has attached a ribbon cable to the rear of the expansion sockets, and then connected two sockets to the cable. These were used to mount a ROM module and 16K RAM module inside the case and leave the 4 expansion slots for interface modules.


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