PM Opc ROR

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)

« Back to Instruction set