Intel 210200-002 manual CMP Compare, Immediate Operand with Accumulator

CMP COMPARE

CMP

Encoding:

Memory or Register Operand with Register Operand:

I00111 0 d w Imod reg rIm I

if d = 1 then LSRC = REG, RSRC = EA else LSRC = EA, RSRC = REG

Immediate Operand with Memory or Register Operand:

11 00000 s w I mod 111 rIm I data Idata if s:w=o11

LSRC= EA, RSRC = data

Immediate Operand with Accumulator:

I00111 1 0 w I data I data if w=1

if w = 0 then LSRC = AL, RSRC = data else LSRC = AX, RSRC = data

CMP Operands	Clocks*	Transfers	Bytes	CMP Coding Examples
register, register	3	-	2	CMP BX, CX
register, memory	9(13) + EA	-	2-4	CMP OH, ALPHA
memory, register	9(13) +EA	-	2-4	CMP [BP + 2], SI
register, immediate	rif	-	3-4	CMP BL, 02H
memory, immediate	10(14)+ EA	-	3-6	CMP [BX].RAOAR [01],
				3420H
accumulator, immediate	4	-	2-3	CMP AL, 00010000B

*b(w): where b denotes the number of clock cycles for byte operands and w denotes the number of clock cycles for word operands.

2-67