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MICROPROCESSOR INSTRUCTION REFERENCE->DCR

b:# DCR s    Decrement operand s


s <- s - 1


Flags
    

S	Set if result -ve, else cleared
Z	Set if result zero, else cleared
AC	Set if half carry, else cleared
P	Set if parity even else cleared
C	Not affected

s:	No of bytes	Cycles
		8085	8080A
r	1	4	5
M	1	10	10

register r may be one of A,B,C,D,E,H,L
M is memory addressed by the HL
register pair