The green LED only goes on when the right password is used.

With this simple project it is possible to light a green LED when the right password is inserted. The LEDs can be replaced with something else, but a whole lot of extra knowlegde is required to include that to this project. 

 

Materials used:

 - Arduino Uno

 - Breadboard (30-pins is enough)

 - A few wires 

 - 2 LEDs (green and red)

 - 4 buttons

 - 10 resistors (2x 220 Ohm, 4x 1k Ohm, 4x 10k Ohm)

 

To change the password, go to the second line in the code and change the order of the numbers inside of the curly brackets.

 

It is possible to change the length of the password, just follow the steps written as comments in the code.