PM Opc ROL

ROL = Rotate Left

Hex	Mnemonic	Cycles
CE 94	ROL A	12
CE 95	ROL B	12
CE 96 nn	ROL [N+#nn]	20
CE 97	ROL [HL]	16

Execute

A       = Register A
B       = Register B
[N+#nn] = Memory: (I shl 16) or (N shl 8) or #nn
[HL]    = Memory: (I shl 16) or HL

; ROL Ds
;
; Ds = Source/Destination

Ds = (Ds SHL 1) OR (Ds SHR 7)

Description

"8-Bits Destination" bits are rotated left by 1.

Conditions

Zero: Set when result is 0

Carry: Set when bit 0 of the result is 1

Sign: Set when bit 7 of the result is 1

Overflow remain unchanged

Examples

; A = 0x04
ROL A
; A = 0x08
; F = (Zero=0):(Carry=0):(Sign=0)

; B = 0x45
ROL B
; B = 0x8A
; F = (Zero=0):(Carry=0):(Sign=1)

; B = 0x84
ROL B
; B = 0x15
; F = (Zero=0):(Carry=1):(Sign=0)

; [HL] = 0x80
ROL [HL]
; [HL] = 0x01
; F = (Zero=0):(Carry=1):(Sign=0)

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