## CMP = Compare (16-Bits)

Hex | Mnemonic | Cycles
--- | --- | ---
D4 nn nn | CMP BA, #nnnn | 12
D5 nn nn | CMP HL, #nnnn | 12
D6 nn nn | CMP X, #nnnn | 12
D7 nn nn | CMP Y, #nnnn | 12
CF 6C nn nn | CMP SP, #nnnn | 16
CF 18 | CMP BA, BA | 16
CF 19 | CMP BA, HL | 16
CF 1A | CMP BA, X | 16
CF 1B | CMP BA, Y | 16
CF 38 | CMP HL, BA | 16
CF 39 | CMP HL, HL | 16
CF 3A | CMP HL, X | 16
CF 3B | CMP HL, Y | 16
CF 5C | CMP SP, BA | 16
CF 5D | CMP SP, HL | 16

### Execute

    #nnnn    = Immediate unsigned 16-Bits
    BA       = Register BA: (B shl 8) or A
    HL       = Register HL: (H shl 8) or L
    X        = Register X
    Y        = Register Y
    SP       = Register SP (Stack Pointer)

    ; CMP Sc2, Sc
    ;
    ; Sc2 = Source 2
    ; Sc  = Source

    (discarded) = Sc2 - Sc

### Description

"16-Bits Source 2" subtracts with "16-Bits Source", result is discarded.

This instruction is used to compare values.

### Conditions

Zero: Set when result is 0

Carry: Set when result is < 0

Overflow: Set when result overflow 16-bits signed range (< -32768 OR > 32767)

Sign: Set when bit 15 of the result is 1

### Examples

    ; BA = 0x2EF0
    CMP BA, $1337
    ; BA = 0x2EF0
    ;      0x1BB9 (0x2EF0 - 0x1337 = 0x(0)1BB9)
    ; F = (Zero=0):(Carry=0):(Overflow=0):(Sign=0)

    ; HL = 0xBB7E
    ; BA = 0xCF12
    CMP BA, HL
    ; HL = 0xBB7E
    ; BA = 0xCF12
    ;     0xEC6C (0xCF12 - 0xBB7E = 0x(1)EC6C)
    ; F = (Zero=0):(Carry=1):(Overflow=0):(Sign=1)

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