// Define the pin for the LED
#define LED_PIN 9

void setup() {
  // Set the LED_PIN as an OUTPUT
  pinMode(LED_PIN, OUTPUT);
}

void loop() {
  // Turn the LED on
  digitalWrite(LED_PIN, HIGH);
  // Wait for 1 second (1000 milliseconds)
  delay(1000);
  
  // Turn the LED off
  digitalWrite(LED_PIN, LOW);
  // Wait for 1 second (1000 milliseconds)
  delay(1000);
}