doorLock.ino.txt

#include<Servo.h>// the header for servo predefined by arduino

Servo servo;// it defines a servo 

void setup()
{
  pinMode(13,OUTPUT);
  pinMode(7,INPUT);
  pinMode(12,OUTPUT);
  servo.attach(8);//the servo will be controlled by pin 8
  servo.write(0);//sets servo to 0 degree position
  Serial.begin(9600);
}

void loop()
{
  //code block for intrusion detection begins
  digitalWrite(12,LOW);
  delayMicroseconds(2);
  digitalWrite(12,HIGH);
  delay(10);
  digitalWrite(12,LOW);

  int t=pulseIn(7,HIGH);
  int dis=(t*0.034)/2;

  if(dis>4)
  {
  digitalWrite(13,HIGH);
  }
  else
  {
  digitalWrite(13,LOW);//comment
  }
  //code block for intrusion detection ends
  //code block for bluetooth control
  if(Serial.available()==1)//checks if any new input is available
  {
  String data=Serial.readString();//reading the input that has been communicated
  if(data=="A")//this signal depends on the app
  servo.write(90);
  else if(data=="a")// the turn off signal
  servo.write(0);
}
}