int led = 13;                
int sensor = 2;              
int state = LOW;             
int val = 0;                 

void setup() {
  pinMode(led, OUTPUT);      
  pinMode(sensor, INPUT);    
  Serial.begin(115200);      
}

void loop(){
  val = digitalRead(sensor);   
  if (val == HIGH) {           
    digitalWrite(led, HIGH);   
    delay(100);                
    
    if (state == LOW) {
      Serial.println("Motion detected!"); 
      state = HIGH;             
    }
  } 
  else {
    digitalWrite(led, LOW);     
    delay(200);                
    
    if (state == HIGH){
      state = LOW;              
    }
  }
  

  Serial.println("Motion undetected!");
  delay(300);  
}