const int pulseSensorPin = A0; // Pulse Sensor is connected to analog pin A0
const int ledPin = 13;         // Onboard LED pin

unsigned int rawValue;
unsigned long currentTime;
unsigned long previousTime = 0;
unsigned int heartRate;

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

void loop() {
  rawValue = analogRead(pulseSensorPin);
  currentTime = millis();

  // Check for the start of a heartbeat
  if (rawValue > 550 && (currentTime - previousTime) > 600) {
    digitalWrite(ledPin, HIGH); // Turn on LED
    previousTime = currentTime;

    // Calculate heart rate (beats per minute)
    heartRate = 60000 / (currentTime - previousTime);

    Serial.print("Heart Rate: ");
    Serial.println(heartRate);
  } else {
    digitalWrite(ledPin, LOW); // Turn off LED
  }
}