Security is a prime concern in our day-today life. Everyone wants to be as much secured as possible. Keypad based password is one of the many method and the most common and easy one to provide security to any system.
In this project, we will learn How to design a password protected system using a 4X4 keypad with AVR ATmega32 microcontroller. Here, the user will enter a 4 digit numeric password to gain access of the system and after gaining access of the system, the user presses different keys of the 4X4 keypad and the system displays the value of the pressed key in a 16X2 alphanumeric LCD. The user enters the 4 digit numeric password by pressing different keys of the 4X4 keypad one by one. For each key pressed, a * is displayed in the 16X2 alphanumeric LCD. After entering 4 digits of the password, the microcontroller compares the entered password with the set password (1234 in our case) and displays the result of the comparison in the 16X2 alphanumeric LCD as Correct Password or Wrong Password. Once the correct password is entered, the user can press different keys of the 4X4 keypad and the 16X2 alphanumeric LCD displays the value of the pressed keys. Try entering different combinations of passwords and see the output.
| Key Pressed | Key Value |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 4 |
| 5 | 5 |
| 6 | 6 |
| 7 | 7 |
| 8 | 8 |
| 9 | 9 |
| 0 | 0 |
| * | * |
| # | # |
| A | A |
| B | B |
| C | C |
| D | D |
Softwares Required
For more detail: 4X4 Keypad based Password with ATmega32 and LCD Display
