FANDOM


Cpu






The Instruction set below can be downloaded in Word format from the Crib Sheets page.


Instruction

Syntax

Description

ADC

ADC #op1

ADC op1

ADC op1,X/Y

ADC (op1,X)

ADC (op1), Y

add with carry

AND

AND #op1

AND op1

AND op1,X/Y

AND (op1,X)

AND (op1), Y

and (with accumulator)

ASL

ASL A

ASL op1

ASL op1,X

arithmetic shift left

BCC

BCC op1

branch on carry clear

BCS

BCS  op1

branch on carry set

BEQ

BEQ  op1

branch on equal (zero set)

BIT

BIT op1

bit test

BMI

BMI op1

branch on minus (negative set)

BNE

BNE op1

branch on not equal (zero clear)

BPL

BPL op1

branch on plus (negative clear)

BRK

BRK

interrupt

BVC

BVC op1

branch on overflow clear

BVS

BVS op1

branch on overflow set

CLC

CLC

clear carry

CLD

CLD

clear decimal

CLI

CLI

clear interrupt disable

CLV

CLV

clear overflow

CMP

CMP #op1

CMP op1

CMP op1,XY)

CMP (op1,X)

CMP (op1),Y)

compare (with accumulator)

CPX

CPX #op1

CPX op1

compare with X

CPY

CPY #op1

CPY op1

compare with Y

DEC

DEC #op1

DEC op1

decrement

DEX

DEX

decrement X

DEY

DEY

decrement Y

EOR

EOR #op1

EOR op1

EOR op1,X/Y

EOR (op1,X)

EOR (op1), Y

exclusive or (with accumulator)

INC

INC op1

INC op1,X

increment

INX

INX

increment X

INY

INY

increment Y

JMP

JMP op1

JMP (op1)

jump

JSR

JSR op1

jump subroutine

LDA

LDA #op1

LDA op1

LDA op1,X

LDA op1,Y

LDA (op1,X)

LDA (op1),Y

load accumulator

LDX

LDX A

LDX  op1

LDX op1,X

load X

LDY

LDY A

LDY  op1

LDY op1,X

load Y

LSR

LSR A

LSR op1

LSR op1,X

logical shift right

NOP

NOP

no operation

ORA

ORA #op1

ORA op1

ORA op1,X

ORA op1,Y

ORA (op1,X)

ORA (op1),Y

or with accumulator

PHA

PHA

push accumulator

PHP

PHP

push processor status (SR)

PLA

PLA

pull accumulator

PLP

PLP

pull processor status (SR)

ROL

ROL A

ROL op1

ROL op1,X

rotate left

ROR

ROR A

ROR op1

ROR op1,X

rotate right

RTI

RTI

return from interrupt

RTS

RTS

return from subroutine

SBC

SBC #op1

SBC op1

SBC op1,X

SBC op1,Y

SBC (op1,X)

SBC (op1),Y

subtract with carry

SEC

SEC

set carry

SED

SED

set decimal

SEI

SEI

set interrupt disable

STA

STA op1

STA op1,X

STA op1,Y

STA (op1,X)

STA (op1),Y

store accumulator

STX

STX op1

STX op1,X

store X

STY

STY op1

STY op1,Y

store Y

TAX

TAX

transfer accumulator to X

TAY

TAY

transfer accumulator to Y

TSX

TSX

transfer stack pointer to X

TXA

TXA

transfer X to accumulator

TXS

TXS

transfer X to stack pointer

TYA

TYA

transfer Y to accumulator