Book Image

BeagleBone Black Cookbook

Book Image

BeagleBone Black Cookbook

Overview of this book

There are many single-board controllers and computers such as Arduino, Udoo, or Raspberry Pi, which can be used to create electronic prototypes on circuit boards. However, when it comes to creating more advanced projects, BeagleBone Black provides a sophisticated alternative. Mastering the BeagleBone Black enables you to combine it with sensors and LEDs, add buttons, and marry it to a variety of add-on boards. You can transform this tiny device into the brain for an embedded application or an endless variety of electronic inventions and prototypes. With dozens of how-tos, this book kicks off with the basic steps for setting up and running the BeagleBone Black for the first time, from connecting the necessary hardware and using the command line with Linux commands to installing new software and controlling your system remotely. Following these recipes, more advanced examples take you through scripting, debugging, and working with software source files, eventually working with the Linux kernel. Subsequently, you will learn how to exploit the board's real-time functions. We will then discover exciting methods for using sound and video with the system before marching forward into an exploration of recipes for building Internet of Things projects. Finally, the book finishes with a dramatic arc upward into outer space, when you explore ways to build projects for tracking and monitoring satellites.
Table of Contents (16 chapters)
BeagleBone Black Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Device Tree / advanced – adding DT overlay to run a custom cape


BeagleBone Black introduced the idea of Device Tree overlays that provide even more functionality to DT by modifying the tree in user space, typified in our prior example. With DT overlay, there is no need to reboot.

We saw in our earlier section on sysfs usage the directory/extension .capemgr, which refers to cape manager. The BeagleBone kernel uses cape manager as a way to provide dynamic loading and unloading of device tree fragments both at compile time and from user space after the device has booted. We will demonstrate this again here; except this time, we will use DT to enable a custom cape, one which delivers audio I/O functionality to the BBB.

Getting ready

In addition to your usual BBB setup, we will use Audio Cape Rev. B, available from CircuitCo (http://boardzoo.com/index.php/beaglebone-black/bone-audio.html). Attach the cape to your BBB's header stack, following the orientation shown in the following pictures:

Note

If...