int T=500;
void setup() {
DDRD = 0xFF;

}

void loop() {
  for (int x=PD0;x<=PD7;x = x+1){
  PORTD=~(1<<x);
  delay(T);
  }
  for (int x=PD7;x--;){
  PORTD=~(1<<x);
  delay(T);
  }
  for(int i=0;i<=2;i++){
  PORTD = 0b11111111;
  delay(T);
  PORTD = 0b00000000;
  delay(T);
  }
  for(int i=0;i<=2;i++){
  PORTD = 0b10101010;
  delay(T);
  PORTD = 0b00000000;
  delay(T);}
}