CMP

 


Opcode

Operand

Description

CMP

R

M

Compare register or memory with accumulator

 

 

—  The contents of the operand (register or memory) are compared with the contents of the accumulator.

 

—  Both contents are preserved .

—  The result of the comparison is shown by setting the flags of the PSW as follows:


 

—  if (A) < (reg/mem): carry flag is set

—  if (A) = (reg/mem): zero flag is set

—  if (A) > (reg/mem): carry and zero flags are reset.

—  Example: CMP B or CMP M

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