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version 2011-09-19

CMPU : CoMPare Unsigned

Substract the second operand (snd register) from the first operand (either si4 or imm16). Change the borrow bit of the result : set if an unsigned borrow occured, clear otherwise.

Internally, this works just like the SUB instruction but the result is never written. It is helpful for clearing or setting the carry flag

The CMPS instruction is identical but performs a signed comparison.