//first sketch-03

int redLedPin = D3;
int oraLedPin = D2;

void setup(){
    pinMode(oraLedPin, OUTPUT);
    pinMode(redLedPin, OUTPUT);
}

void loop() {
  // red on, orange off
  digitalWrite(oraLedPin, HIGH);
  digitalWrite(redLedPin, LOW);
  delay(3000);

  // red off, orange on
  digitalWrite(oraLedPin, LOW);
  digitalWrite(redLedPin, HIGH);
  delay(3000);
}