Book Image

ARM?? Cortex?? M4 Cookbook

By : Dr. Mark Fisher
Book Image

ARM?? Cortex?? M4 Cookbook

By: 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

Performing arithmetic operations


Writing a program that adds two numbers together may seem like a trivial task. We obviously need to declare three variables, two to hold values of the numbers to be added, known as addends, and another to hold the sum. The following recipe illustrates some problems that arise due to word length.

How to do it…

The following steps demonstrate how to perform arithmetic operations:

  1. Create a new folder and name it addTwoNums_c3v0. Invoke uVision5 and create a new project named addTwoNums within this folder.

  2. Use the RTE manager to select the MCBSTM32F400 evaluation board and configure it as we did for helloWorld_c2v0, from the Writing to console Window recipe in Chapter 2, C Language Programming.

  3. Copy the files, Serial.c, Serial.h, and Retarget.c, from the helloWorld_c2v0 recipe into the folder.

  4. Create a new source file named addTwoNums.c and enter the following program. Please note that we're using the folding editor feature to omit boilerplate code:

    /**************...