Eprom Modules for the HP 75

[Paul Berger (Canada)]

All of the ROMs plugged into the front as well as ROMs contained in the expansion pod are bank selected in and out of the same 8K window in the address space. There are also two internal ROMs in the 75 that share this space. The 75's bank selecting scheme using specific addresses to select and deselect a ROM. It is up to the ROM to monitor the appropriate addresses to know when to turn on and turn off. There are pins on the front ports that the plugin ROM uses to identify which port it is in and which addresses it should monitor. The ROM section of the service guide shows a map of the addresses used.

I would be interested in knowing what connector Dominique plans to use.