RichardBrown384 / Eichhoernchen

Acorn Archimedes A3000 Emulator in C++23
https://github.com/RichardBrown384/archimedes
MIT License
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[FEATURE] MEMC could support RAM sizes other than 4Mb #15

Open RichardBrown384 opened 2 months ago

RichardBrown384 commented 2 months ago

Is your feature request related to a problem? Please describe. It would be nice if the MEMC could support RAM sizes other than 4Mb.

Describe the solution you'd like The MEMC can support 512Kb, 1Mb, and 2Mb of RAM configurable at start.

Describe alternatives you've considered Not implementing this feature. Ideally you want to have as much RAM as possible. It would only be necessary if we wanted to support software that insisted on having less RAM.

Additional context The physical ram is not linear and RISC OS uses knowledge of this to detect the amount of RAM present.

After referring to the VTI manual we probably need to map the address onto the Row/Column Address registers correctly. See Appendix A RAM Address Bus.