HP 71B Ports

[J-F Garnier]

(06-11-2016 02:24 PM)Dave Frederickson Wrote:  When only one module is plugged into the dual HP-IL adapter I presume it works fine.

Yes, it works with one module in position 1 (lower position).
It could also work (I didn't test) with a HP-IL module in position 1 and a front port module in position 2.

Quote:When two HP-IL modules are plugged in, what does SHOWPORT report as being plugged into Port .05?

SHOW PORT will report the two HPIL ROMs in ports 0.05 and 0.07. The two holes 0.04 and 0.06 are used by the HP-IL mailboxes.

Quote:Its funny, I've configured all sorts of modules in Port 5 with Emu71 but had never thought of trying it with a physical 71.

A hardly known feature of the HP71 configuration code is that it manages ports 0 to *7*, even if ports 6 and 7 are not existent in the physical machine. So, since a long time, it is possible to configure modules in ports 6 and 7 in Emu71/DOS :-)