## NEG = Negate

Hex | Mnemonic | Cycles
--- | --- | ---
CE A4 | NEG A | 12
CE A5 | NEG B | 12
CE A6 nn | NEG [N+#nn] | 20
CE A7 | NEG [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

    ; NEG Ds
    ;
    ; Ds = Source/Destination

    Ds = 0 - Ds

### Description

8-Bits Destination is negated.

### Conditions

Zero: Set when result is 0

Carry: Set when result is not 0

Overflow: Set when result is 0x80

Sign: Set when bit 7 of the result is 1

### Examples

    ; A = 0x01
    NEG A
    ; A = 0xFF (0 - 0x01 = 0xFF)
    ; F = (Zero=0):(Carry=1):(Overflow=0):(Sign=1)

    ; B = 0x00
    NEG B
    ; B = 0x00 (0 - 0x00 = 0x00)
    ; F = (Zero=1):(Carry=0):(Overflow=0):(Sign=0)

    ; [HL] = 0x80
    NEG [HL]
    ; [HL] = 0x80 (0 - 0x80 = 0x80)
    ; F = (Zero=0):(Carry=1):(Overflow=1):(Sign=1)

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