#include <avr/io.h>

#include <util/delay.h>

 

#define BLINK_DELAY_MS 1000

 

int main (void)

{

 

 DDRB |= (0x20);
DDRD |= (0x08);
 

 while(1) {

  PORTB |= (0x20);

  _delay_ms(BLINK_DELAY_MS);
  PORTB &= 0xDF; // you can do PORTB &= ~(0x20)
  _delay_ms(BLINK_DELAY_MS);


PORTD = PORTD | 0x08;
  _delay_ms(BLINK_DELAY_MS);

PORTD = PORTD & 0xF7;
  _delay_ms(BLINK_DELAY_MS);


  

 }

}