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Post by mirkosoft on May 14, 2016 19:39:08 GMT
Hi!
I'm working on multitasking, better to say simultasking (Simulated Multitasking).
I have many resources etc. but one simple Q, maybe you ask: What a stupid Q...
Ok, no matter, for me is hard to make multitasking for both 8502 and Z80 (even two Z80) in The Ace...
Always when I look at instruction set of Z80 my eyes are on PC instructions and easy access...
So this Q is only for 8502 or X65 CPUs
How ML Monitor gets PC value which is shown in registry dump at start or R command?
Of course no matter which MLM, but especially C128's MLM... I know that it is possible to find in ROM disassembly.
Thank you for understanding!
Miro
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Post by VDC 8x2 on May 14, 2016 20:04:13 GMT
The MLM starts after a brk command. The brk command puts the program counter and the status reg on the stack.
The MLM get the value from the stack and adjusts.
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Post by mirkosoft on May 14, 2016 22:03:42 GMT
Ok, BRK. I mean it will need look how adjusts value from stack, I know that it's only from stack, but addressing is 16-bit, so it needs look at. My opinion is that programming Z80 is much easier and effective with less memory costs. But for Z80 only I don't give away my Commodore 128 and Mega 65... Like I said: Commodores changed my life
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Post by VDC 8x2 on May 15, 2016 0:39:36 GMT
subtract 2 from address, if I remember correctly.
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