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SUB r     Subtract without Carry     Rabbit 4000/5000 Instruction

Opcode	Instruction	Operation
----	SUB r	A = A - r
7F 97	SUB A	A = A - A
7F 90	SUB B	A = A - B
7F 91	SUB C	A = A - C
7F 92	SUB D	A = A - D
7F 93	SUB E	A = A - E
7F 94	SUB H	A = A - H
7F 95	SUB L	A = A - L

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 r (any of the registers A, B, C, D, E, H, or L) from A. The result is stored in A. The Rabbit 4000/ 5000 assemblers view "SUB A,r" and "SUB r" as equivalent instructions.

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