int clockPin = 2;
int ledPin = 13;

void setup() {
  pinMode(clockPin, OUTPUT);
  pinMode(ledPin, OUTPUT);
  Serial.begin(9600);
}

void loop() {
  digitalWrite(clockPin, HIGH);
  digitalWrite(ledPin, HIGH);
  delay(500);
  
  digitalWrite(clockPin, LOW);
  digitalWrite(ledPin, LOW);
  delay(500);
  
  Serial.println("Clock pulse generated");
}