Posts by raxrip

    The fact that you had to unlock the STM32 before you could flash it, could mean it has been used before. Did you buy it from China? I flashed a few KFF's but never had to unlock the STM32. But I sometimes buy programmable chips from China, always advertised as "brand new, genuine and unused" and all of it has been proven to be untrue.

    Same happened to me when I ordered from China and at the time I was working on my dumper tool I use to order from China in hope that they came read protected. (RDP1 or RDP2) Usually they came with RDP1 but I also once got an RDP2 protected chip which required double glitching to get the firmware out. One funny thing is that this RDP2 protected chip could also be downgraded to RDP1 and then RDP0 by erasing the content so the chip worked flawlessly after this. Info from STM states that after setting RDP2 it would be impossible to downgrade again :)

    And in case some one is wondering how to dump a read protected chip then wallet.fail did a great job on this that was introduced at CCC some time ago. This is of course only the first step but helped me on the right path.

    Problem is that the VIC don't see the ROM using the bus handler so 6502 need to copy data from ROM to RAM and that is why the slow 16 fps.

    This is bitmap mode so if using text mode the CPU should be able to copy a whole screen within a raster scan.

    If I am not wrong in Ultimax Mode the VIC should to access data from the catridge.

    As far as I know ultimax mode uses the vic handler and that handler is running in an infinite loop and I don't know if code could be injected to it.

    Kim also wrote a comment on that handler saying it is using 100% CPU so don't know if that could be used.


    In c64_interface.c:

    #define C64_BUS_HANDLER(name) <- The one I use atm


    ---


    // This supports VIC-II reads from the cartridge (i.e. character and sprite data)

    // but uses 100% CPU - other interrupts are not served due to the interrupt priority

    #define C64_VIC_BUS_HANDLER(name)

    Seems to be plenty of juice left for running code on the STM when using the C64 bus handler.


    Problem is that the VIC don't see the ROM using the bus handler so 6502 need to copy data from ROM to RAM and that is why the slow 16 fps.

    This is bitmap mode so if using text mode the CPU should be able to copy a whole screen within a raster scan.

    HI

    I am looking at the source code for the KFF and was wondering if the STM chip can be used like a Super CPU. That is NOT simulating the Super CPU itself but using the STM chip to update some GFX memory the C64 can see (or should I say the VICII chip can see)

    Looking at the KFF code I found this comment:
    "
    This supports VIC-II reads from the cartridge (ie character and sprite data) but uses 100% CPU - other interrupts are not served due to the interrupt priority"

    So I guess the STM chip is 100% busy when data is fetched from it but I assume the STM could run some code when the VICII is drawing the border and that there are now sprites there?

    Alternately using a different STM chip like the STMH750 running at 480MHz with a new PCB.


    You think there is room fore some game code to run on the STMF405 combined with the VICII is fetching data from it?


    regards