const int reedPin = D2; 
const int ledPin = D0;

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

void loop() {
  int reedState = digitalRead(reedPin);

  if (reedState == LOW) {
    digitalWrite(ledPin, HIGH); // Turn on the LED
    Serial.println("Magnet detected!"); 
  } else {
    digitalWrite(ledPin, LOW); // Turn off the LED
    Serial.println("No magnet."); 
  }

  delay(100);
}