There is almost no practical upper limit Bob if you use the Address line shifting hardware approach. The S100 bus has 24 Address lines (16MB). If you switch RAM banks by switching in/out RAM cards via a hardware port, in theory 8 bits X RAM card size (I have not seen all bits/256 hardware). However again this is way more than you would need.
See here for more info:-
You can run a non banked version of CPM3 in about 60K or less, however two banks are the norm, more banks are really only used for disk buffering/speed.
On Friday, March 20, 2015 at 12:30:36 PM UTC-7, Bob Bell wrote:
Good afternoon oh wise group,
Happy Friday! and Happy Spring!
I am working on my implementaton of CPM3.
I think DR says this in the manual somewhere, but I can't put my finger on it right now: Does anyone know off the top of their heads...
What is the maximum number of memory banks that CPM3 will work with?
I know the minimum is 2.
And what is practical?
I'll have a relatively vast amount of memory (like 1MB), so I could implement 16 banks, but I have a feeling that's overkill.
Thanks to everyone for helping!
Bob Bell