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

Basic commands for systemd services


systemd is modified via a configuration file, rather than a shell script. Before you perform anything too ambitious, we will take a look at how we stop, start, enable, and disable a service.

Our example will reset and reconfigure a key service that will run in your Debian distribution: the systemd-timedated.service by default.

How to do it...

Perform the following steps:

  1. Navigate to the systemd directory (root user) with the following code:

    # cd /lib/systemd/system
    
  2. Let's see what services are running, using a command that serves as the control utility for systemd, as shown in the following code:

    # systemctl
    

    You should see a long, fat list of services that show their current status on the system. The items appended with the .service filename are systemd services and controllable via the command line.

  3. Run this command to stop the service:

    systemctl stop systemd-timedated.service
    
  4. Now, disable the service using the following code:

    systemctl disable systemd-timedated...