Post Thu May 29, 2014 5:17 pm

RAM page support

I've never programmed used bank switching, but now I'm developing a new external interface to convert a 16Kb Spectrum to a machine very close to a plus 3 machine but with 512Kb of RAM, and due to it, I'm starting to be interested of this kind of programming.

I know now that ZXBasic has not support for bank-switching.

I have a suggestion about the possibility of support it natively and then support 512Kb of RAM too. The method to change the page above 128Kb is the same that the used in Pentagon, ie using bits 6 and 7 of the same port than 128Kb ($7FFD).

Could be very interesting to do it, because if we do it manually we can only use it for data, as a very fast disk, but not for code. The best way is to implement it natively. It is not possible to do that with a library.

The main challenge could be to use the same addresses for different functions.