DCR

 


Opcode

Operand

Description

DCR

R

M

Decrement register or memory by 1

 

 

—  The contents of register or memory location are decremented by 1.

—  The result is stored in the same place.

—  If the operand is a memory location, its address is specified by

the contents of H-L pair.

—  Example: DCR B or DCR M

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