#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;
 }

}