SHL = Shift Left
| Hex | Mnemonic | Cycles |
|---|---|---|
| CE 84 | SHL A | 12 |
| CE 85 | SHL B | 12 |
| CE 86 nn | 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)