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BANK MAP confusion

  • Hi,


    I'm trying to wrap my head around all this banks and maps memory maps thing. I read the pieces about it in the user manual some times now, but I just don't understand it.


    Can somebody lay it down for me in a simple way? .. this is strictly about mega65 mode - not c65 or c64.


    What memory is available to me when the machine starts? That is bank 0 I assume?

    How do switch banks (in assembler)?

    What happens when I have code running in bank 0 and decide to change banks? The next line of code would be executed in the new bank? Would I then have to make sure my code is copied to all banks I use?

    The manual mentions 4 methods of bank switching. When would I use which method? .. and how exactly do I do it? I mean, on the c64 it was simple with setting $01 depending on what "layer" you needed. I cannot find documentation that helps me understand how/what I can/should do?
    How is mapping different from banking?
    How do I access the "slow" memory?

    Sorry, but as you can see I am a bit confused. I hope some kind soul can explain this in a way an old, seasoned c64 assembler programmer can understand :)


    Trap

  • Hi Trap/Bonzai

    first thing you should keep in mind, when using the banks, there is a huge change in the config between the last official

    Commodore ROM 911210 and the MEGA65 ROM 92XXXX.
    If you're using the Commodore ROM, i would suggest to have a look Zaadii s video. he explains it pretty good.
    https://www.youtube.com/watch?v=5yGxGrHcrzA
    And for comparison, Bit Shifter described the changes in Paul's guest blog post between the 911210 and the 92XXXX pretty good:
    https://c65gs.blogspot.com/202…it-shifter-improving.html

  • Ah yes. I've seen Zaadii's video. I still feel I miss some things, but maybe its just a matter of playing around.


    Well, we are meeting this weekend in our group and we plan to explore the m65 a lot. I hope the conclusion could be some updates to the m65 book. We'll see.


    Is it safe to assume that the current implementation is the final? It would be extremely difficult to develop for a platform if the fundamentals aren't fully in place? As an example, my group mate just told me that most of the included BASIC demos stopped working after updating to the latest firmware. I haven't verified this and don't know the exact details, but thought it was important information to share.

  • In that case i would suggest to use the 911210 ROM. There won't be changes done with it.