Keypad Modules are expensive so to relace them in this video i am going to show you how you can make combinational lock using push button and Arduino. You will need Arduino, 8x LEDs, 6X Buttons, ...

PWM pins work the same way across all Arduino boards, so you don't need to go out of your way to buy a Mega if you already have a board supporting PWM. On the Uno, Nano, and Mini, the PWM pins are ...