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SLL bb,BCDE
SLL bb,JKHL     Shift Left Logical     Rabbit 4000/5000 Instruction

Opcode	Instruction	Operation
----	SLL bb,BCDE	BCDE = {BCDE[30,0],0}   CF = B[7]   bb = bb - 1 repeat while bb != 0
DD A8	SLL 1,BCDE	the operation happens 1 time
DD A9	SLL 2,BCDE	the operation happens 2 times
DD AB	SLL 4,BCDE	the operation happens 4 times
----	SLL bb,JKHL	JKHL = {JKHL[30,0],0}   CF = J[7]   bb = bb - 1 repeat while bb != 0
FD A8	SLL 1,JKHL	the operation happens 1 time
FD A9	SLL 2,JKHL	the operation happens 2 times
FD AB	SLL 4,JKHL	the operation happens 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

Shifts to the left the bits of the data in register BCDE or JKHL. Bits 0 through 30 are each shifted to the next highest-order bit position (bit 0 moves to bit 1, etc.). The highest-order bit (bit 31 of BCDE or JKHL) is shifted to the C flag. Bit 0 is reset. See the figure below.

Figure 20: The bit logic of the SLL instruction

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