In the last installment of our tutorial series we built a simple circuit on a breadboard and programmed an ATmega168 to make it run. That proves that you know how to follow directions, but the eureka ...

Bitwise XOR compares each binary digit of the two inputs. The XOR returns a 1 when only one of the two digits is a 1, otherwise, it returns a zero for that position. Let’s say the coordinates were 3, ...