Arduino Chess Clock

by benhur.goncalves @ instructables.com:

Hey folks! After making an Arduino smartwatch just last week, I received many complaints,or tips, to use a RTC (real-time clock) module. That’s because the Arduino timer is not very precise, it can lose a couple a minutes along a full work day. Luckly, I had one of those modules at my home, I decided to give it a try. However, I faced some challenges along the way, as I can show you here.

Arduino Chess Clock – [Link]