const int pinLED1=8;
const int pinLED2=7;
void setup() {
pinMode(pinLED1, OUTPUT);
pinMode(pinLED2, OUTPUT);
}

void loop() {
  digitalWrite(pinLED1, HIGH);
  digitalWrite(pinLED2, LOW);
  delay(500);

  digitalWrite(pinLED1, LOW);
  digitalWrite(pinLED2, HIGH);
  delay(500);

}