ROR = Rotate Right

Hex Mnemonic Cycles
CE 9C ROR A 12
CE 9D ROR B 12
CE 9E nn ROR [N+#nn] 20
CE 9F ROR [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
    
; ROR Ds
;
; Ds = Source/Destination

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

    

Description

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

Conditions

Zero: Set when result is 0

Carry: Set when bit 7 of the result is 1

Sign: Set when bit 7 of the result is 1

Overflow remain unchanged

Examples

; A = 0x04
ROR A
; A = 0x02
; F = (Zero=0):(Carry=0):(Sign=0)
    
; B = 0x45
ROR B
; B = 0xA2
; F = (Zero=0):(Carry=1):(Sign=1)
    
; B = 0x84
ROR B
; B = 0x42
; F = (Zero=0):(Carry=0):(Sign=0)
    
; [HL] = 0x01
ROR [HL]
; [HL] = 0x80
; F = (Zero=0):(Carry=1):(Sign=1)
    

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