ARM Cortex M4 Cookbook

297 Pages·2012·7.77 MB·English

by  Dr. Mark Fisher

ARM® Cortex® M4
Cookbook
Over 50 hands-on recipes that will help you develop amazing
real-time applications using GPIO, RS232, ADC, DAC, timers,
audio codecs, graphics LCD, and a touch screen
Dr. Mark Fisher
BIRMINGHAM - MUMBAI
ARM® Cortex® M4 Cookbook
Copyright © 2016 Packt Publishing
All rights reserved. No part of this book may be reproduced, stored in a retrieval system,
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First published: March 2016
Production reference: 1020316
Published by Packt Publishing Ltd.
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ISBN 978-1-78217-650-3
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Table of Contents
Preface v
Chapter 1: A Practical Introduction to ARM® CORTEX® 1
Introduction 1
Installing uVision5 2
Linking an evaluation board 4
Running an example program 8
Writing a simple program 9
Understanding the simple use of GPIO 16
Estimating microcontroller performance 21
Chapter 2: C Language Programming 25
Introduction 25
Configuring the hardware abstraction layer 26
Writing a C program to blink each LED in turn 31
Writing a function 37
Writing to the console window 42
Writing to the GLCD 52
Creating a game application – Stage 1 55
Creating a game application – Stage 2 61
Debugging your code using print statements 68
Using the debugger 71
Chapter 3: Programming I/O 75
Introduction 75
Performing arithmetic operations 76
Illustrating machine storage classes 83
Configuring GPIO ports 85
Configuring UART ports 95
Handling interrupts 101
Using timers to create a digital clock 105
i
Table of Contents
Chapter 4: Assembly Language Programming 109
Introduction 109
Writing Cortex-M4 assembly language 111
Passing parameters between C and the assembly language 116
Handling interrupts in assembly language 121
Implementing a jump table 127
Debugging assembly language 131
Chapter 5: Data Conversion 135
Introduction 135
Setting up the ADC 137
Configuring general-purpose timers 144
Using timers to trigger conversions 150
Setting up the DAC 153
Generating a sine wave 157
Chapter 6: Multimedia Support 163
Introduction 163
Setting the RTE for the I2C Peripheral Bus 164
How to use the LCD touchscreen 167
Writing a driver for the audio codec 171
How to use the audio codec 179
How to use the camera 184
Designing bitmapped graphics 189
Ideas for games using sound and graphics 194
Chapter 7: Real-Time Signal Processing 195
Introduction 195
Configuring the audio codec 196
How to play prerecorded audio 205
Designing a low-pass digital filter 208
How to make an audio tone control 215
Chapter 8: Real-Time Embedded Systems 219
Introduction 219
Multithreaded programs using event flags 222
Multithreaded programs using mailboxes 229
Why ensuring mutual exclusion is important when accessing shared
resources 232
Why we must use a mutex to access the GLCD 237
How to write a multithreaded Pong game 241
Debugging programs that use CMSIS-RTOS 244
ii
Table of Contents
Chapter 9: Embedded Toolchain 249
Introduction 249
Installing GNU ARM Eclipse 250
Programming the MCBSTM32F400 evaluation board 255
How to use the STM32CubeMX Framework (API) 260
How to port uVision projects to GNU ARM Eclipse 269
Index 273
iii

Preface
This book begins with an introduction to the ARM Cortex family and covers its basic concepts.
We cover the installation of the ARM uVision Integrated Development Environment and topics,
such as target devices, evaluation boards, code configuration, and GPIO. You will learn about
the core programming topics that deal with structures, functions, pointers, and debugging
in this book. You will also learn about various advanced aspects, such as data conversion,
multimedia support, real-time signal processing, and real-time embedded systems. You will
also get accustomed with creating game applications, programming I/O, and configuring GPIO
and UART ports. By the end of this book, you will be able to successfully create robust and
scalable ARM Cortex-based applications.
What this book covers
Chapter 1, A Practical Introduction to ARM® Cortex®, shows you how to compile, download,
and run simple programs on an evaluation board.
Chapter 2, C Language Programming, introduces you to writing programs in C, a high-level
language that was developed in the 1970s and is popular among embedded-system
developers.
Chapter 3, Programming I/O, investigates some of the functions that configure I/O devices, and
you will gain an understanding of what is involved in writing I/O interfaces for other targets.
Chapter 4, Assembly Language Programming, explains how to write functions in assembly
language. Assembly language is a low-level programming language that is specific to particular
computer architecture. Therefore, unlike programs written high-level languages, programs
written in assembly language cannot be easily ported to other hardware architectures.
Chapter 5, Data Conversion, introduces approaches to data conversion, namely analog to
digital conversion and vice versa. This chapter also covers the principal features used by
microcontrollers for data conversion.
v
Preface
Chapter 6, Multimedia Support, discusses support for various multimedia peripherals,
which are discrete components connected to the microcontroller by a bus. Support for
an LCD touchscreen, audio codec, and camera peripherals is a very attractive feature of
the STM32F4xxx microcontroller, and selecting an evaluation board that includes these
peripherals, although more expensive, will be covered in this chapter.
Chapter 7, Real-Time Signal Processing, introduces you to Digital Signal Processing (DSP) and
reviews the ARM Cortex M4 instruction set support for DSP applications. This chapter will walk
through a DMA application using the codec, followed by designing a low-pass filter.
Chapter 8, Real-Time Embedded Systems, shows you how to write a multithreaded program
using flags for communication and ensuring mutual exclusion when accessing shared resources.
Chapter 9, Embedded Toolchain, teaches you how to install the GNU ARM Eclipse toolchain
for the Windows Operating System and to build and run a simple Blinky program on
the MCBSTM32F400 evaluation board. This chapter will also show you how to use the
STM32CubeMX Framework (API) and how to port projects to GNU ARM Eclipse.
What you need for this book
You require the Keil Development Board MCBSTM32F400 (v1.1) and ARM ULINK-ME for
this book.
Who this book is for
This book is aimed at those with an interest in designing and programming embedded
systems. These could include electrical engineers or computer programmers who want to
get started with microcontroller applications using the ARM Cortex M4 architecture in a short
time frame. This book's recipes can also be used to support students learning embedded
programming for the first time. Basic knowledge of programming using a high-level language
is essential but those familiar with other high-level languages such as Python or Java should
not have too much difficulty picking up the basics of embedded C programming.
Sections
In this book, you will find several headings that appear frequently (Getting ready, How to do it…,
How it works…, There's more…, and See also).
To give clear instructions on how to complete a recipe, we use these sections as follows:
vi
Preface
Getting ready
This section tells you what to expect in the recipe, and describes how to set up any software or
any preliminary settings required for the recipe.
How to do it…
This section contains the steps required to follow the recipe.
How it works…
This section usually consists of a detailed explanation of what happened in the previous
section.
There's more…
This section consists of additional information about the recipe in order to make the reader
more knowledgeable about the recipe.
See also
This section provides helpful links to other useful information for the recipe.
Conventions
In this book, you will find a number of text styles that distinguish between different kinds of
information. Here are some examples of these styles and an explanation of their meaning.
Code words in text, database table names, folder names, filenames, file extensions,
pathnames, dummy URLs, user input, and Twitter handles are shown as follows: "Copy the
function named SystemClock_Config() from the example."
A block of code is set as follows:
#ifdef __RTX
extern uint32_t os_time;
uint32_t HAL_GetTick(void) {
return os_time;
}
#endif
vii