Quote:
Originally Posted by litwr
Thanks. It is now not actual. However it sounds like another Moto's oddity for me. I needed to save C flag because every MOVE (it is yet another oddity) clears it! I could find a way to write my code without this saving. I don't know any other processor which works so unusually with arithmetic flags. x86 has PUSHF/POPF, LAHF/SAHF. They can be quite useful although rather rarely.
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Call this a failed theory if you want, but the carry on the 68k has been made so that the flag for testing isn't the same as for multi-precision.
Therefore any data move will change C (usually cleared, exactly like a cmp with zero would have done). But not X. Maybe you can use X in your code rather than C ? Why do you want to preserve the carry anyway ?