RL b,JKHL     Rotate Left Through Carry     Rabbit 4000 Instruction

Opcode	Instruction	Clocks	Operation
----	RL b,JKHL	4 (2,2)	{CF,JKHL} = {JKHL,CF}   b = b - 1 repeat while b != 0
FD 68	RL 1,JKHL	4 (2,2)	{CF,JKHL} = {JKHL,CF}   b = b - 1 repeat while b != 0
FD 69	RL 2,JKHL	4 (2,2)	{CF,JKHL} = {JKHL,CF}   b = b - 1 repeat while b != 0
FD 6B	RL 4,JKHL	4 (2,2)	{CF,JKHL} = {JKHL,CF}   b = b - 1 repeat while b != 0

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

Description

Rotates JKHL to the left with the C flag. Each bit in the register moves to the next highest-order bit position (bit 0 moves to bit 1, etc.) while the C flag moves to bit 0 and bit 31 moves to the C flag. This operation happens b number of times. See Figure 2 for an illustration.