char A[] = {0x01, 0x02, 0x04, 0x08, 0x10, 0x20, 0x40, 0x80};

void setup() {
  // put your setup code here, to run once:
  // for(int i=22; i<30; i++){
  //   pinMode(i, OUTPUT);
  // } 
  DDRA = 0xFF;
}

void loop() {
  // put your main code here, to run repeatedly:
  for(int i=0; i<8; i++){
    PORTA = A[i]; delay(1000);
  }
  for(int i=7; i>=0; i--){
    PORTA = A[i]; delay(1000);
  }
}