How do you determine a 71B memory-mapped I/O device address?

[rprosperi]

(03-31-2021 12:21 AM)Giuseppe Donnini Wrote:  The best place to start, in my opinion, would be Nathan Meyers article "Soft Configuration Enhances Flexibility of Handheld Computer Memory", published in the July 1984 issue of the Hewlett-Packard Journal (p. 10-13).

The most advanced and detailed treatment can be found in the HP-71 Software Internal Design Specification. Chapter 2 of the first volume, entitled "System Startup and Memory Configuration", gives a general overview, while all the gritty details can be gleaned from the actual source code and its comments in the third volume (starting at address #10192h).

I've read the former article (many times!) and I don't think it addresses the device MMIO allocation/scheme with much detail (if any), its focus is more on configuring ROM/RAM blocks in the various ports.

As for the 2nd paragraph, this is indeed terrifyingly complicated, but is also likely the only source in actual documentation. Perhaps JFG or Hans know and can save the day...?