Book Image

GNU/Linux Rapid Embedded Programming

By : Rodolfo Giometti
Book Image

GNU/Linux Rapid Embedded Programming

By: Rodolfo Giometti

Overview of this book

Embedded computers have become very complex in the last few years and developers need to easily manage them by focusing on how to solve a problem without wasting time in finding supported peripherals or learning how to manage them. The main challenge with experienced embedded programmers and engineers is really how long it takes to turn an idea into reality, and we show you exactly how to do it. This book shows how to interact with external environments through specific peripherals used in the industry. We will use the latest Linux kernel release 4.4.x and Debian/Ubuntu distributions (with embedded distributions like OpenWrt and Yocto). The book will present popular boards in the industry that are user-friendly to base the rest of the projects on - BeagleBone Black, SAMA5D3 Xplained, Wandboard and system-on-chip manufacturers. Readers will be able to take their first steps in programming the embedded platforms, using C, Bash, and Python/PHP languages in order to get access to the external peripherals. More about using and programming device driver and accessing the peripherals will be covered to lay a strong foundation. The readers will learn how to read/write data from/to the external environment by using both C programs or a scripting language (Bash/PHP/Python) and how to configure a device driver for a specific hardware. After finishing this book, the readers will be able to gain a good knowledge level and understanding of writing, configuring, and managing drivers, controlling and monitoring applications with the help of efficient/quick programming and will be able to apply these skills into real-world projects.
Table of Contents (26 chapters)
GNU/Linux Rapid Embedded Programming
Credits
About the Author
About the Reviewer
www.PacktPub.com
Customer Feedback
Preface

Chapter 8. Universal Serial Bus - USB

Now, it's time to take a look at the Universal Serial Bus, that is, a versatile bus widely used in modern PCs that allows people to connect an electronic device to a computer. For instance, a hard disk, a keyboard, or a serial device (as seen in the previous chapter) can be all connected to a computer through the same USB port.

After a brief introduction about what this bus is and how it works, we'll show you the different types of USB devices and how they are supported in the Linux kernel. We'll see how our embedded kits can act as USB hosts in order to manage a barcode reader and how we can use the BeagleBone Black as a USB device in order to exchange data with a host PC. In this case, we will show the multi gadget and the configfs one which allows the developer to switch between different functions dynamically.