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stefandrissen / SAM-MOD-player

SAM MOD player, an Amiga MOD player for the SAM Coupé
https://www.worldofsam.org/products/sam-mod-player
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support external RAM (megabyte) #2

Closed stefandrissen closed 5 years ago

dandoore commented 5 years ago

With regards to #6 can this be expanded to multiple One Meg interfaces?

stefandrissen commented 5 years ago

Good point!

It should not be too difficult, the larger problem however will be #6, and until #6 is done, there is no point :-)

stefandrissen commented 5 years ago

Actually, I think it will automatically work since:

Each 1 Mb External Memory unit is divided into 64 pages of 16k each, selected by the first 6 bits of ports 128 and 129. The most significant two bits of each port select one of the four possible 1 Mb External Memory units.

And being "good" assembly code I'm not checking any boundaries, so megabyte 1 will automatically flow over to megabyte 2 :-) You will need to configure your megabytes "normally" - ie 1,2,3,4

stefandrissen commented 5 years ago

4mb

stefandrissen commented 5 years ago

released - timing needs some cleaning up, but this also applies to non-megabyte...