[Coco] 6309 microprocessor project: 11-05-2003

John Collyer johncollyer at zoominternet.net
Wed Nov 5 17:18:06 EST 2003


6309 microprocessor project.

Hello,

The emulator's memory module is done.  It gets it's memory from calling the
win32 api and is designated as read/write/execute, this is to support the
special opcode $11FF.  The emulator memory model follows Paul Barton's NoCan
32MB/64MB interface, but stops at 16MB.  It uses the MMU extension registers
located at $FF80-$FF8F along with the MMU registers at $FFA0-$FFAF.

It also has support for the Multi-Pak and allows you to hold up to four 32K
ROM cartridges.  Whenever you use the front switch on the Multi-Pak you'll
get a RESET, but you can change the active cartridge by using the software
latch located at $FF7F.  It can tell if you have a 32K or 16K ROM cartridge
in the slot by checking the bits MC0, MC1 located in $FF90.

I'm still writing it in assembly language, so it's pretty darn fast.  Next
it's on to the hardware module, and I'll bet it'll be a long hard slog!


More later.

John Collyer




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