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SLA bb,BCDE
SLA bb,JKHL     Shift Left Arithmetic     Rabbit 4000/5000 Instruction

Opcode	Instruction	Operation
----	SLA bb,BCDE	BCDE = {BCDE[30,0],0}   CF = B[7]   bb = bb - 1 repeat while bb!=0
DD 88	SLA 1,BCDE	repeat the operation 1 time
DD 89	SLA 2,BCDE	repeat the operation 2 times
DD 8B	SLA 4,BCDE	repeat the operation 4 times
----	SLA b,JKHL	JKHL = {JKHL[30,0],0}   CF = J[7]   bb = bb - 1 repeat while bb!=0
FD 88	SLA 1,JKHL	repeat the operation 1 time
FD 89	SLA 2,JKHL	repeat the operation 2 times
FD 8B	SLA 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 left the bits of BCDE or JKHL. Bits 0 through 30 are each shifted to the next highest-order bit position (bit 0 moves to bit 1, etc.). Bit 31 is shifted to the C flag. Bit 0 is reset.

Figure 18: The bit logic of the SLA instruction.

The operation happens bb number of times, which can be 1, 2 or 4.