This is just a simple program I wrote for an Arduino Mega 2560 board with a generic ultra-sonic sensor and a 16x2 LCD display board. The main point for me is just to learn how to write C++ and gain ...

PIN Code Access: Secure the system with a 6-digit PIN. LCD Display: 16x2 LCD for user interaction and status updates (e.g., "Enter Pin", "Alarm Active", "Motion Detected"). Keypad Input: A 4x4 matrix ...