PM Opc SHL

SHL = Shift Left

Hex	Mnemonic	Cycles
CE 84	SHL A	12
CE 85	SHL B	12
CE 86	SHL [N+#nn]	20
CE 87	SHL [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

; SHL Ds
;
; Ds = Source/Destination

Ds = Ds SHL 1

Description

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

NOTE: This instruction can be used as an unsigned integer multiplication by 2.

Conditions

Zero: Set when result is 0

Carry: Set when the old bit 7 was 1

Sign: Set when bit 7 of the result is 1

Overflow remain unchanged.

Examples

; A = 0x04 (4)
SHL A
; A = 0x08 (8)
; F = (Zero=0):(Carry=0):(Sign=0)

; B = 0x45 (69)
SHL B
; B = 0x8A (138)
; F = (Zero=0):(Carry=0):(Sign=1)

; B = 0x84 (138)
SHL B
; B = 0x14 (20)
; F = (Zero=0):(Carry=1):(Sign=0)

; [HL] = 0x80 (128)
SHL [HL]
; [HL] = 0x00 (0)
; F = (Zero=1):(Carry=1):(Sign=0)

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