Marko Mäkelä wrote: > On the C128 MMU, EXROM and GAME are general purpose input/output pins. > In C128 mode, you can use them as outputs: the PLA doesn't care about > them. If you programmatically switch to C64 mode, you can set EXROM > and GAME as you wish, but you can't control them afterwards, since the > MMU won't be addressable in the C64 mode. > > So, as I understand this, in order to make a cartridge that supports 128mode, I need to put the ROM /CE on one switch (to bank it in an out), and EXROM (and game) on another switch, in order to force 64 mode (or for use on a real 64). I wonder if that should also be reflected on an address line on the EPROM, so different boot roms get mapped in depending on machine mode (128 versus 64) Jim Message was sent through the cbm-hackers mailing listReceived on 2009-03-26 04:41:32
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