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SBC A,(HL)     Subtract Through Carry     Rabbit 4000/5000 Instruction

Opcode	Instruction	Operation
7F 9E	SBC A,(HL)	A = A - (HL) - CF

Clocks	8-Bit Access	16-Bit Unaligned	16-Bit Aligned
Rabbit 4000	7	n/a	n/a
Rabbit 5000	7	7	5

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 in HL 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,(HL)" and "SBC (HL)" as equivalent instructions. In the latter case, A is used even though it is not explicitly stated.

The opcode for this instruction is different than the same instruction in the Rabbit 2000, 3000 and 3000A.