Thief Prevention

Thief Prevention

const int sensorPin = A0;    
const int ledPin = 9;        

int sensorValue = 0;         
int sensorMin = 1023;       
int sensorMax = 0;           

int buzzer = 8;
void setup() {
  
  pinMode(13, OUTPUT);
  pinMode(buzzer, OUTPUT);
  digitalWrite(13, HIGH);
  Serial.begin(9600);
  
  while (millis() < 1000) {
    sensorValue = analogRead(sensorPin);

    if (sensorValue > sensorMax) {
      sensorMax = sensorValue;
    }

    if (sensorValue < sensorMin) {
      sensorMin = sensorValue;
    }
  }

  digitalWrite(13, LOW);
}

void loop() {
  // read the sensor:
  sensorValue = analogRead(sensorPin);

  sensorValue = map(sensorValue, sensorMin, sensorMax, 0, 255);

  sensorValue = constrain(sensorValue, 0, 255);
  int val = 255-sensorValue;
  Serial.println(val);
  
  if (val==255){
    tone(buzzer,1000);
  }
  else{
    noTone(buzzer);
  }
  analogWrite(ledPin, val);
}