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SBC (IX+d)
SBC (IY+d)     Subtract Through Carry     Rabbit 2000/3000/4000/5000 Instruction

Opcode	Instruction	Operation
DD 9E d	SBC (IX+d)	A = A - (IX+d) - CF
FD 9E d	SBC (IY+d)	A = A - (IY+d) - CF

Clocks	8-Bit Access	16-Bit Unaligned	16-Bit Aligned
Rabbit 2000/3000/4000	9	n/a	n/a
Rabbit 5000	10	9	8

Flags				ALTD			IOI/IOE
S	Z	L/V	C	F	R	SP	S	D
·	·	V	·	·	·		·

Description

Subtracts the C flag and the data whose address is:

• the sum of IX and the 8-bit signed displacement d, or

• the sum of IY and the 8-bit signed displacement d

from A. The result is stored in A.

These operations output an inverted carry:

• The C flag is set if A is less than the data being subtracted from it.

• The C flag is cleared if A is greater than the data being subtracted from it.

• The C flag is unchanged if A is equal to the data being subtracted from it.

The Rabbit 4000/5000 assemblers view "SBC A,(IX+d)" and "SBC (IX+d)" as equivalent instructions. The same is true for "SBC A,(IY+d)" and "SBC (IY+d)."