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SBC A,r     Subtract Through Carry     Rabbit 4000/5000 Instruction

Opcode	Instruction	Operation
--	SBC A,r	A = A - r - CF
7F 9F	SBC A,A	A = A - A - CF
7F 98	SBC A,B	A = A - B - CF
7F 99	SBC A,C	A = A - C - CF
7F 9A	SBC A,D	A = A - D - CF
7F 9B	SBC A,E	A = A - E - CF
7F 9C	SBC A,H	A = A - H - CF
7F 9D	SBC A,L	A = A - L - CF

Clocks	8-Bit Access	16-Bit Unaligned	16-Bit Aligned
Rabbit 4000	4	n/a	n/a
Rabbit 5000	2	2	2

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

Description

Subtracts the C flag and the data in r (one of A, B, C, D, E, H or L) from A. The result is stored in A.

The Rabbit 4000/5000 assemblers view "SBC A,r" and "SBC r" as equivalent instructions. In the latter case, A is used even though it is not explicitly stated.

The opcodes for these instructions are different than the same instructions in the Rabbit 2000, 3000 and 3000A.