ошибка proteus: неверный код операции 0xFFFF на ПК =0x068C

Question

Это мой код:

      START:
    LDI R18, 0XFF
    OUT DDRB, R18 //LET PORT B AS OUTPUT
    LDI R16, 0B01110101
    OUT TCCR0A, R16
    LDI R17, 0B01110101
    OUT TCCR0B, R17
    LDI R24, 0XFF
    OUT DDRD, R24 // LET PORT AS INPUT
    OUT OCR0A, R18


MAIN:

    IN R18, PINB //LOAD PORT B TO R18
    CPI R18, 0B00000000 //CHECK IF R18 == 0
    BREQ SPEED1 // JUMP TO SPEED1 IF R18 == 0
    OUT OCR0A, R16
    OUT OCR0B, R17

    IN R18, PINB //LOAD PORTB TO R18
    CPI R18, 0B00000001 //CHECK IF R18 == 1
    BREQ SPEED2 // JUMP TO SPEED2 IF R18 == 1
    OUT OCR0A, R16
    OUT OCR0B, R17

    IN R18, PINB //LOAD PORTB TO R18
    CPI R18, 0B00000010 //CHECK IF R18 == 2
    BREQ SPEED3 // JUMP TO SPEED3 IF R18 == 2
    OUT OCR0A, R16
    OUT OCR0B, R17

    IN R18, PINB //LOAD PORTB TO R18
    CPI R18, 0B00000011 //CHECK IF R18 == 1
    BREQ SPEED4 // JUMP TO SPEED4 IF R18 == 3
    OUT OCR0A, R16
    OUT OCR0B, R17

    RJMP MAIN

SPEED1:
    LDI R16, 0B00000001
    OUT PORTD, R16
    LDI R17, 255
    RET

SPEED2:
    LDI R16, 0B00000001
    OUT PORTD, R16
    LDI R17, 180
    RET

SPEED3:
    LDI R16, 0B00000001
    OUT PORTD, R16
    LDI R17, 100
    RET

SPEED4:
    LDI R16, 0B00000001
    OUT PORTD, R16
    LDI R17, 0
    RET

Это мой Протей:

И КОГДА Я БЕГУ, ЭТА ОШИБКА ПРОИЗОШЛА:
Invalid opcode 0xFFFF at PC=0x8C02

Я понятия не имею, что там произошло. любая помощь будет оценена.