PM_Opc_CMP16.md

== 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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