avr assembly led

.equ XTAL = 16000000 ;16 mHz

.equ BTN  = 2 ;Pinnumber of PORT_D
.equ LED  = 3 ;Pinnumber of PORT_D

.def temp1 = r16
.def temp2 = r17

    ;Init stackpointer
    ldi temp1, HIGH(RAMEND)
    out SPH,   temp1
    ldi temp1, LOW(RAMEND)
    out SPL,   temp1

    ;Set led pin to output
    ldi temp1, (1 << LED)
    out DDRD, temp1

loop:
    in    temp1, PIND
    sbrc  temp1, BTN ;Check if button is pressed
    rcall led_toggle
    rjmp  loop

led_toggle:
    andi  temp1, (1 << LED)
    ldi   temp2, (1 << LED)
    eor   temp1, temp2 ;xor the led pin
    out   PORTD, temp1
    ldi   temp2, 0xFF
led_toggle_0:
    dec   temp2
    rcall delay5ms
    brne  led_toggle_0
    ret

; DELAY 50µs (variable)
delay50us:
    push temp1
    ldi  temp1, (XTAL*50/4)/1000000 ;$C8
delay50us_0:
    dec  temp1
    nop
    brne delay50us_0
    pop  temp1
    ret

; DELAY 5ms (variable)
delay5ms:
    push temp1
    push temp2
    ldi  temp1, (XTAL*5/603)/1000 ;$84
delay5ms_0:
    ldi  temp2, $C9
delay5ms_1:
    dec  temp2
    brne delay5ms_1
    dec  temp1
    brne delay5ms_0
    pop  temp2
    pop  temp1
    ret