eZ80
®
CPU
User Manual
UM007714-0908 CPU Instruction Set
120
CP A, (IX/Y+d)
Compare with Accumulator
Operation
A–(IX/Y+d)
Description
The (
IX/Y
+
d
) operand is the 8-bit value stored in the memory location specified by the
contents of the Index Register, IX or IY, added to the two’s-complement displacement
d
.
This 8-bit value is compared with (subtracted from) the contents of the accumulator, A.
The execution of this instruction does not affect the contents of the accumulator or the
(
IX/Y
+
d
) operand.
Condition Bits Affected
Attributes
S Set if result is negative; reset otherwise.
Z Set if A = (IX/Y+d); reset otherwise.
H Set if borrow from bit 4; reset otherwise.
P/V Set if overflow: reset otherwise.
N Set.
C Set if borrow; reset otherwise.
Mnemonic Operand ADL Mode Cycle Opcode (hex)
CP A,(IX+d)X 4 DD, BE, dd
CP.S A,(IX+d)1 5 52, DD, BE, dd
CP.L A,(IX+d)0 5 49, DD, BE, dd
CP A,(IY+d)X 4 FD, BE, dd
CP.S A,(IY+d)1 5 52, FD, BE, dd
CP.L A,(IY+d)0 5 49, FD, BE, dd