I have two HP 71Bs and they display independant RAM differently with SHOW PORT.

The earlier metal bottomed 1984 71B will only display ports that have been declared independent with FREE PORT, thus SHOW PORT will give:

0 4096 1
0.01 4096 1
0.05 16384 2

However, the later plastic bottomed 1988 71B displays both ports that have been declared independent with FREE PORT and ports that have not. SHOW PORT on this 71B gives:

0 4096 1
0.01 4096 1
0.05 16384 2
0.02 4096 0
0.03 4096 0

As I am new to the 71B, this confused me at first but perhaps the later model 71B's had the provision to display all internal RAM ports used or not. If you MEM(0.03), the 0.03 port above, you get an error device not found message even though SHOW PORT displays it. Then again, something might be wrong with one of the 71Bs as they should diplay the same way with SHOW PORT.

Along with the above issue, the 1988 71B came with a 34K memory module inserted in slot one. It doesn't seem to work (or I have not installed it correctly - have no information on how to do this at this point) as SHOW PORT diplays:

1 0 0

When the 34K module is inserted in the 1984 71B, SHOW PORT displays nothing about it. Again, the newer 1988 71B shows ports in use or not - even with external memory modules.

Anybody ever notice this?



This is a known problem with the earliest HP71s. Get the SHOWPORT lex file and install it on the old unit and the problem will be fixed.

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