void setup() {
  pinMode(4,INPUT_PULLUP);     // PIR sensor as input
pinMode(12, OUTPUT);
Serial.begin(115200);
}
void loop() {
  int a=digitalRead(4);
  if (a==1)
  {
    digitalWrite(12, HIGH);
    Serial.println("Motion detected");
  }
  else
  {
    digitalWrite(12, LOW);
  Serial.println("Not detected");  
}
delay(2000);
  }