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

How to use the LCD touchscreen


The LCD touchscreen used by the MCBSTM32F400 evaluation board is a resistive film giving a resolution of 4000 × 4000 (that is, far greater than the GLCD). This recipe extends touchScreenDemo_c2v0 and illustrates how to use the LCD touchscreen.

How to do it…

Perform the following steps to use the LCD touchscreen:

  1. Return to touchScreenDemo_c2v0 and open the project.

  2. Use the RTE manager to add Software ComponentBoard Support for the Graphic LCD (in addition to the Touchscreen). Click Resolve and then OK.

  3. Open touchScreenDemo.c, and include the following headers:

    #include <stdio.h>
    #include "stm32f4xx_hal.h"
    #include "cmsis_os.h"
    #include "Driver_I2C.h"
    #include "Board_GLCD.h"
    #include "GLCD_Config.h"
    #include "Board_Touch.h"
  4. Define the following macros, global variables, and function prototypes:

    // The size of the touch-screen co-ordinates system.
    #define SCREEN_TS_WIDTH  4000
    #define SCREEN_TS_HEIGHT 4000
    
    #define wait_delay HAL_Delay
    
    /* Globals */
    extern GLCD_FONT...