#define F_CPU 8000000UL

#include <avr/io.h>
#include <avr/interrupt.h>
#include <util/delay.h>
#include "util.h"

int main(void) {
    DDRB = 0xff;
    for (;;) {
	PORTB = 0xAA;
	delay_ms(500);
	
	PORTB = 0xFF;
	delay_ms(500);
   }
}