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
About the Author
About the Reviewer

Designing a low-pass digital filter

Joseph Fourier discovered that a complex signal could be described by a sum of sinusoids that is known as a Fourier series, and applying this idea enables us to visualize a signal frequency spectrum. A spectrum analyzer is a device that allows the frequency content of a signal to be displayed and measurements to be made. Two parameters, known as magnitude (amplitude) and phase, describe a sinusoidal signal. The magnitude spectrum describes the amplitude of each sinusoidal component that is summed, and the phase spectrum describes its associated phase. Often, we ignore the phase information and focus on the magnitude spectrum, but for some applications, particularly those that involve feedback, the phase of the signal is very important.

The magnitude spectrum of a pure 10 kHz sinusoidal signal is illustrated in the following diagram (the left panel) and that of a sampled version of the signal (the right panel):

When we sample a signal, the steps in the digitized...