An Arduino project implementing a security alarm system featuring PIN code access via a 4x4 keypad, status updates on a 16x2 LCD, motion detection using an HC-SR04 ultrasonic sensor, and ...

For more advanced security applications, you might also want to explore our RFID door lock system using Arduino, which shares similar hardware ... memory module using I2C interface) in it. 16x2 I2C ...

User enters the password using the keypad. LCD displays whether access is granted or denied. You can modify the code to control a door motor/lock mechanism.