void setup() {
pinMode(2, OUTPUT);
pinMode(3, OUTPUT);
pinMode(4, OUTPUT);
pinMode(5, OUTPUT);
pinMode(6, OUTPUT);
pinMode(7, OUTPUT);
pinMode(8, OUTPUT);
}

void loop() {
int pin = 8;
while (pin >= 1){
  digitalWrite(pin, HIGH);
  delay(1000);
  digitalWrite(pin,LOW);
  pin--;
} 
}