#include <avr/io.h>
#include <util/delay.h>
// LED på OCR0A

int main(void)
{
  TCCR0A = (1 << COM0A1) | (0 << COM0A0)
          | (0 << COM0B1) | (0 << COM0B0)
          | (1 << WGM01) | (1 << WGM00);
  TCCR0B = (0 << WGM02)
          | (0 << CS02) | (1 << CS01) | (0 << CS00);
  OCR0A = 0;
  DDRB |= (1 << PB0); 

  uint8_t dir = 1;

  while (1)
  {
    if (dir)
    {
      if (OCR0A <= 254)
      {
        OCR0A += 1;
      }
      else
      {
        OCR0A = 255;
        dir = 0;
      }
    }
    else
    {
      if (OCR0A >= 1)
      {
        OCR0A -= 1;
      }
      else
      {
        OCR0A = 0;
        dir = 1;
      }
    }
    _delay_ms(10);
  }          
}