Anyone have the PINOUT of the Front Ports on the 71B?


I have the signals (I think). From reading the Hardware IDS, I believe the following are the signals: BUS[0:3], *STR, *CD, Vdd, Gnd, Din, Dout, *INT, *IR14, Halt (except for port 1). I could be wrong on these, but there are 13 pins and this is my guess on the 13 signals. Anyone feel free to correct me, if I'm wrong.

However, I can't find any description on which pin is which. I can figure this out, in time, but I was wondering if anyone knows the pin numbering on the HP-71B Front Ports?


Edited: 21 Aug 2006, 2:08 p.m.


There are 13 contact positions on a module. Of these 13 possible contacts, 11 are common. So, I presume the two that are not common are the Din and Dout (but I could be wrong). Further, it's easy to spot Vdd and Gnd. And the "module pulled" contact seems obvious. However that still leaves 8 to figure out.

Here are two photos.

Port 3 is interesting, in that it has a pad, recessed further in, that can't be reached by a module. Anyone know what this is for?

Edited: 22 Aug 2006, 1:22 a.m.


This puzzle is easy:

Pin 1: GND

Pin 2: *Int (module pulled)

Pin 3: OD /HALT (depends on port)

Pin 4: IR14 (I/O handshake and wakeup)

Pin 5: Daisy out (only for Prot Extender)

Pin 6: Daisy in

Pin 7: *C/D Data/Command signal

Pin 8: Strobe

Pin 9: B0 (I/O 0)

Pin10: B1 (I/O 1)

Pin11: B2 (I/O 2)

Pin12: B3 (I/O 3)

Pin13:Vdd (6V)
(Sorry, I can't get the line-breaks right)

I have this Pins printed out on a paper that says 'CHHU V1N1'. I don't know if it is on the Museum's DVD, or on TOS!


Thanks this helps a lot. I had already determined which was *CD, *STR, Bus[0:3], Vdd, Gnd and Module Pulled (but not INT) but the rest were a mystery. I was also originally wrong on the Din/Dout. I have one of those LogicPort Analyzers and it made it fairly easy to spot *STR, *CD and Bus[0:3]


Edited: 23 Aug 2006, 4:11 p.m.

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