To program these chips, [Aaron] first had to wire up the microcontroller into a circuit. This was just a bit of perf board, a resistor, a few caps, and a USB A plug.

Making a clock with a common microcontroller like an Arduino isn’t very difficult. However, if you’ve tried it, you probably discovered that keeping track of wall time is difficult with… ...

To make things a little easier on yourself, Arduino shield-maker 1Sheeld shows off how to hack a clock to change color depending on traffic conditions.