Build a Binary Clock with Elixir and Nerves

Chapter 5Build the Clock’s Circuit

This is the part of the project that all hardware lovers crave. You’ll be planning and building the hardware that will make up the clock. It’s the shortest part of the book but might take the longest to execute depending on how much experience you have.

For the first time, we’ll use a constant current LED driver. Since that much is a mouthful, we’ll sometimes refer to it as a constant current driver, or even driver. Here’s what it does.

As you work in this chapter, you’ll work inside a new mix project called Clock. It will have the implementation for the entire binary clock. Like software, hardware systems are built in layers. The interfaces between the layers make it easy to isolate services and let engineers ...