Book Image

ARM® Cortex® M4 Cookbook

By : Mark Fisher, Dr. Mark Fisher
Book Image

ARM® Cortex® M4 Cookbook

By: Mark Fisher, Dr. Mark Fisher

Overview of this book

Embedded microcontrollers are at the core of many everyday electronic devices. Electronic automotive systems rely on these devices for engine management, anti-lock brakes, in car entertainment, automatic transmission, active suspension, satellite navigation, etc. The so-called internet of things drives the market for such technology, so much so that embedded cores now represent 90% of all processor’s sold. The ARM Cortex-M4 is one of the most powerful microcontrollers on the market and includes a floating point unit (FPU) which enables it to address applications. The ARM Cortex-M4 Microcontroller Cookbook provides a practical introduction to programming an embedded microcontroller architecture. This book attempts to address this through a series of recipes that develop embedded applications targeting the ARM-Cortex M4 device family. The recipes in this book have all been tested using the Keil MCBSTM32F400 board. This board includes a small graphic LCD touchscreen (320x240 pixels) that can be used to create a variety of 2D gaming applications. These motivate a younger audience and are used throughout the book to illustrate particular hardware peripherals and software concepts. C language is used predominantly throughout but one chapter is devoted to recipes involving assembly language. Programs are mostly written using ARM’s free microcontroller development kit (MDK) but for those looking for open source development environments the book also shows how to configure the ARM-GNU toolchain. Some of the recipes described in the book are the basis for laboratories and assignments undertaken by undergraduates.
Table of Contents (16 chapters)
ARM Cortex M4 Cookbook
Credits
About the Author
About the Reviewer
www.PacktPub.com
Preface
Index

Writing a function


Functions (sometimes called subroutines) are used to hide the complexity of underlying program statements, thereby presenting a more abstract view of the program. Abstraction is commonplace in engineering; for example, we can think of a car as comprising subassemblies that include body, engine, gearbox, suspension, and so on. The complexity within these subassemblies is only important to those specialists such as designers, test engineers, and technicians who need to interact with them. For example, the designers of the gearbox don't need to concern themselves with the intricacies of the engine, they just need to know a few important parameters. Functions provide a similar abstraction mechanism. We already met the functions LED_Initialize(); LED_On(), and LED_Off() used to initialize and switch the LEDs. We don't need to know exactly how these functions do their job but only how to use them. C provides functions as a mechanism of achieving hierarchical decomposition. For...