The program designs a home security system with two main modules: 1) an intruder detection system using a PIR sensor to detect humans and alert, and 2) a password-based door lock system. The door lock system uses a numeric keypad to accept a 4-digit password (last 4 digits of the registration number) and an LCD to display whether access is granted or denied. Upon receiving the correct password, a motor is enabled to open the door. If an incorrect password is entered or an intruder is detected, a buzzer is activated. The program is simulated and verified on an Arduino using the Tinkercad circuit simulator.

1. 19bec1224
ChallengingTask-1Home SecuritySystem:
Write a program to designhome securitysystemthatconsistsof twomainmodules(1) Intruder
detection(2) passwordbaseddoorlocksystem.The intruderdetectionsystemconsistsof PIRsensor
interfacedwithprocessingunittodetectandalertunderhumanpresence condition.Inpassword
baseddoorlock systemnumerickeypadtoacceptthe password(last4-digitof yourreg.no) from
userand LCD to displaythe message whetherpermissionisgrantedornot.Upon receivingcorrect
passwordsignal,enablemotortoopenthe door.In case of passwordmismatchor intruder
detectionconditionactivate the buzzer.SimulateandverifythislogiconArduinoUnousing
Tinkercadcircuitsimulator.
APIUsed:
lcd.begin()
lcd.write()
Serial.begin()
delay()
keypad.getKey()
Code:
#include <Keypad.h>
#include <LiquidCrystal.h>
LiquidCrystal lcd(6,7,2,3,4,5);
const byte ROWS= 4;
const byte COLS= 4;
char keys[ROWS][COLS] ={
{'1','2','3','A'},
{'4','5','6','B'},
{'7','8','9','C'},
{'*','0','#','D'}
};

2. byte rowPins[ROWS]={A3,A2,A1,A0};
byte colPins[COLS]={11,10,9,8};
intLCDRow = 0;
intdoor = 12;
inti=0;
intc=0;
char password[4] = {'1','2','2','5'};
intfl = 0;
Keypadkeypad=Keypad( makeKeymap(keys),rowPins,colPins,ROWS,COLS);
voidsetup()
{
Serial.begin(9600);
pinMode(door,OUTPUT);
pinMode(13,INPUT);
pinMode(1,OUTPUT);
lcd.begin(16,2);
lcd.clear();
lcd.setCursor(LCDRow,0);
lcd.print("Enteryourcode:");
delay(3000);
lcd.clear();
}
voidloop()
{
char key= keypad.getKey();

3. if(key)
{
Serial.print(key);
lcd.print("*");
if(password[LCDRow]!=key)
fl=1;
lcd.setCursor(++LCDRow,0);
}
if(LCDRow>=4)
{
if(fl==1)
{
lcd.setCursor(0,1);
lcd.print("WrongPassword");
digitalWrite(1,HIGH);
delay(2000);
digitalWrite(1,LOW);
fl = 0;
lcd.clear();
LCDRow= 0;
}
else
{
lcd.setCursor(0,1);
lcd.print("CorrectPassword");
digitalWrite(door,HIGH);
delay(5000);

4. digitalWrite(door,LOW);
lcd.clear();
fl=0;
LCDRow= 0;
}
}
if(digitalRead(13)==HIGH)
{
digitalWrite(1,HIGH);
delay(2000);
digitalWrite(1,LOW);
delay(2000);
}
}
Output:

5. TinkerCADLink:
https://www.tinkercad.com/things/6tyAyAQuXof-stunning-
curcan/editel?sharecode=QCKpLmdqdMSQQ4wM_pEaIRw2jYl_zxowFtxFUDJqujc
Result:
Thus,the logichasbeenimplementedsuccessfullyandverifiedinTinkercad