#include <avr/io.h>
#include <stdint.h>
#include <avr/interrupt.h>

/* inverteer PB7 na 24 neergaande flanken op PB0 */

ISR(TIMER0_COMP_vect) {
    PORTB ^= 0x80;
}

int main(void) {
    TCCR0 = 0x0E;
    OCR0 = 23;
    TIMSK = 0x02;
    DDRB = 0x80;
    sei();
    while (1);
    return 0;
}