; Registers:
;   r16: timer0 start and stop operations

.MACRO START_BLINK
    ldi     r16,       (1 << OCF0A)                     ; Write Output Compare Flag 0 A to 1
    out     TIFR,      r16                              ; Clear Timer0 interrupt flag register

    clr     r16                                         ; Cleanup register
    out     TCNT0,      r16                             ; Reset Counter to 0

    ldi     r16,        (1 << CS02) | (1 << CS00)       ; Load prescaler value (00000101 = prescaler 1024)
    out     TCCR0B,     r16                             ; Enable clock source

    sbi     PORTB,      PB0                             ; Set LED on
.endm

stop_blink:
    cbi     PORTB,      PB0                             ; Set LED off

    clr     r16                                         ; Cleanup register
    out     TCCR0B,     r16                             ; Stop timer0 by clearing prescaler

    ldi     r16,        (1 << OCF0A)
    out     TIFR,       r16                             ; Clear timer0 interrupt flag register

    reti