int valor;

void setup() {
  Serial.begin(9600);

    for(int i = 2; i <= 6; i++){
        pinMode(i, OUTPUT);
          }
          }

          void loop() {

            valor = analogRead(A0);
              Serial.println(valor);

                if(valor > 600){

                    for(int i = 2; i <= 6; i++){
                          digitalWrite(i, HIGH);
                              }

                                } else {
                                    for(int i = 3; i <= 6; i++){
                                          digitalWrite(i, LOW);
                                              }

                                                  digitalWrite(2, HIGH);
                                                      delay(500);
                                                          digitalWrite(2, LOW);
                                                              delay(500);
                                                                }
                                                                }