// #define PIN LED_BUILTIN
// #define PIN 12
#define PIN 2

void setup() {
  // put your setup code here, to run once:
  pinMode(PIN, OUTPUT);
  Serial.begin(115200);
}

void loop() {
  // put your main code here, to run repeatedly:
  digitalWrite(PIN, HIGH);   // turn the PIN on (HIGH is the voltage level)
  delay(1000);               // wait for a second
  Serial.println("Ping");
  digitalWrite(PIN, LOW);    // turn the PIN off by making the voltage LOW
  delay(1000);               // wait for a second
  Serial.println("Pong");
}