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SRA bb,BCDE
SRA bb,JKHL     Shift Right Arithmetic     Rabbit 4000/5000 Instruction

Opcode	Instruction	Operation
----	SRA bb,BCDE	BCDE = {B[7],BCDE[31,1]}   CF = E[0]   bb = bb - 1 repeat while bb != 0
DD 98	SRA 1,BCDE	repeat the operation 1 time
DD 99	SRA 2,BCDE	repeat the operation 2 times
DD 9B	SRA 4,BCDE	repeat the operation 4 times
----	SRA bb,JKHL	JKHL = {J[7],JKHL[31,1]}   CF = L[0]   bb = bb - 1 repeat while bb != 0
FD 98	SRA 1,JKHL	repeat the operation 1 time
FD 99	SRA 2,JKHL	repeat the operation 2 times
FD 9B	SRA 4,JKHL	repeat the operation 4 times

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

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

Description

Arithmetically shifts to the right the bits of the data in register BCDE or JKHL. Bits 1 through 31 are each shifted to the next lowest-order bit position. The highest-order bit of BCDE or JKHL is shifted into itself and the lowest-order bit is shifted to the C flag. See the figure below.

Figure 21: The bit logic of the SRA instruction.

The instruction repeats the number of times specified by bb, which can be 1, 2 or 4.