#include <avr/io.h>             // for the input/output register

  #include <util/delay.h> 

  #include <stdio.h>

  

  

  int main(void)

  {

  

  DDRB = 0xFF;

  PORTB = 0x01;

  

  

  while(1)

  

  {

  _delay_ms(400);

  PORTB = PORTB*2;

  if(PORTB == 0x40)  PORTB = 0x01;

   }

  

  }