Arduino countdown timer with setup buttons

In this Instructables guide I will show you how to make your own Arduino two digit countdown timer. I made my own circuit by using the ATmega328 micro controller but this is an optional step. In this guide I will help you to make it easily on breadboard by using the Arduino uno board! We will be able to set the timer by pressing the setup buttons. We will use two digits seven segment display, so the maximum countdown time will be 99 seconds.”