Build a Binary Clock with Elixir and Nerves

Chapter 6Write a Clock with a Core

In the last chapter, you made a box of LEDs. In this chapter, you’ll turn it into a clock with beautiful motion. Most of the project will use techniques you’ve seen in this book. Your code will have two boundary layers: one service layer and one hardware layer. The service layer will be a basic GenServer that’s thin and simple, as shown in the following figure.

The figure shows the boundary layer where the GenServer will be, and also some layers you have not encountered in this book. You’ll need a core layer to handle the complex data structure the constant current driver needs to manipulate your LEDs. The layers ...