CP (IY+d)

Operation

A <- A - (IY+d)

Mnemonic

CP

Operands

(IY+d)

b7b6b5b4b3b2b1b0
1 1 1 1 1 1 0 1$FD
1 0 1 1 1 1 1 0$BE
d

Description

The contents of the Index (register pair IY) Register is added to a two's complement displacement d to point to an address in memory. A logical AND operation is performed between the contents of this address and the contents in the Accumulator, the result is stored in the Accumulator.

Condition Bits Affected

Sis set if result is negative, otherwise it is reset.
Zis set if result is 0, otherwise it is reset.
His set if borrow from bit 4, otherwise it is reset.
P/Vis set if overflow, otherwise it is reset
Nis set.
Cis set if borrow, otherwise it is reset.

Example

If the Accumulator contains $63, Index Register IY contains $1000, and memory location $1005 contains $60, then upon the execution of

	CP	(IY+$05)

the P/V flag in the F register is reset.