Controller Takt

/* Bit setzen */

#define sbit(var, bit) ((var) |= (1 << (bit)))

/* Bit löschen */

#define cbit(var, bit) ((var) &= (unsigned)~(1 << (bit)))

/* Byte definieren*/

#define byte uint8_t

/* Bit togglen */

#define tbit(var,bit) ((var) ^= (1 << (bit)))

#include <avr/io.h>

#include <avr/interrupt.h>

int main(void)

{

  sbit (DDRB,PB2);

  init_pwm();

    while(1)

    {

    }

}

void init_pwm (void)

{

  cli();          // Interrupts kurz deaktivieren

  TCCR1B = 4;        // Interrupt = Takt/256

  TIMSK1 |= (1<<TOIE1);   // Interrupt freischalten

  sei();                  // Interrupts global einschalten

}

//Timer 1 Interrupt

ISR(TIMER1_OVF_vect) {

  tbit (PORTB,PB2);

}