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> RL b,BCDE Rotate Left Through Carry Rabbit 4000 Instruction

> Opcode | Instruction | Clocks | Operation
> ---- | RL b,BCDE | 4 (2,2) | {CF,BCDE} = {BCDE,CF} b = b - 1 repeat while b != 0
> DD 68 | RL 1,BCDE | 4 (2,2) | {CF,BCDE} = {BCDE,CF} b = b - 1 repeat while b != 0
> DD 69 | RL 2,BCDE | 4 (2,2) | {CF,BCDE} = {BCDE,CF} b = b - 1 repeat while b != 0
> DD 6B | RL 4,BCDE | 4 (2,2) | {CF,BCDE} = {BCDE,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 BCDE 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.

> Figure 2: Bit logic of the RL instruction

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