Posted By
SVS
on 2022-01-07
03:49:26
 |  Re: Accessing 256k of Plus4?
I own a 256K expanded Plus4. The O.S. works as following, for each access to the banked memory:
a) Disable IRQ;
b) Set bank#
c) Read/write
d) Set bank#3
e) Enable IRQ
The routine must reside inside common area (0..$1000 or 0..$4000).
You can retrive more info on Ultimate map that states the differences between standard O.S. and OS92 (the Solder/Hannes version with banking).
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