// 220 FOR LEDS

void setup() {
  DDRD |= 0x54; // 00010000   
}

void loop() {
  PIND = (1<<PD4) | (1<<PD6) | (1<<PD3); // xxx1xxxx
  delay(500);
  PIND = (0<<PD4) | (0<<PD6) | (0<<PD3); // xxx0xxxx
  delay(500);
}