Electronic Safe Using Arduino Uno

Overview

This project implements an electronic safe using an Arduino Uno, an LCD display, a servo motor, and a keypad. The safe can be locked and unlocked using a secret code entered via the keypad. The state of the safe (locked/unlocked) and the secret code are managed by the SafeState class.

Components

• Arduino Uno
• 16x2 LCD Display
• Servo Motor
• 4x4 Keypad
• Wires and Breadboard

Circuit Diagram

Refer to the provided circuit diagram for wiring details.

Working

This program implements a safe lock system using an Arduino, a keypad, an LCD display, and a servo motor. The system allows the user to lock and unlock the safe by entering a secret code. The main components and their functions are as follows:

• Servo Motor: Controls the locking and unlocking mechanism.
• LCD Display: Provides user interface messages.
• Keypad: Allows the user to input the secret code.
• SafeState: Manages the state of the safe (locked or unlocked) and the secret code.

Algorithm

1. Initialization:

   • Initialize the LCD display, servo motor, and serial communication.
   • Attach the servo motor to the specified pin.
   • Display a startup message on the LCD.
   • Check the initial state of the safe (locked or unlocked) and set the servo position accordingly.

2. Main Loop:

   • Continuously check the state of the safe.
   • If the safe is locked, execute the safeLockedLogic function.
   • If the safe is unlocked, execute the safeUnlockedLogic function.

3. Locking the Safe:

   • Set the servo to the locked position.
   • Update the safe state to locked.

4. Unlocking the Safe:

   • Set the servo to the unlocked position.

5. Displaying Messages:

   • Show a startup message when the system is initialized.
   • Show a wait screen with a progress bar during certain operations.
   • Show an unlock message when the safe is successfully unlocked.

6. Inputting the Secret Code:

   • Prompt the user to enter a 4-digit secret code using the keypad.
   • Display asterisks on the LCD as the user inputs the code.
   • Return the entered code as a string.

7. Setting a New Code:

   • Prompt the user to enter a new secret code.
   • Prompt the user to confirm the new code.
   • If the codes match, update the safe state with the new code.
   • If the codes do not match, display an error message.

8. Safe Locked Logic:

   • Display a locked message on the LCD.
   • Prompt the user to enter the secret code.
   • If the entered code is correct, unlock the safe and display an unlock message.
   • If the entered code is incorrect, display an access denied message.

9. Safe Unlocked Logic:

   • Display an unlocked message on the LCD.
   • Prompt the user to press '#' to lock the safe or 'A' to set a new code.
   • If the user chooses to set a new code, execute the setNewCode function.
   • If the user chooses to lock the safe, lock the safe and display a wait screen.