Did you know...? Difference between RLA and RL A

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Did you know that there are differences between instructions RLA (opcode #17) and RL A (opcode #CB #17)? While RLA is only one byte long and lasts 4 clock cycles, RL A is two bytes long and lasts 8 clock cycles. Additionally, RLA only sets the Carry flag according to the high bit 7 and sets the H and N flags to zero.

RL A additionally sets the S flag if the result was negative, the Z flag if the result was zero, and the P/V flag according to the parity of the result.

mikezt