Book Image

C Programming for Arduino

By : Julien Bayle
Book Image

C Programming for Arduino

By: Julien Bayle

Overview of this book

Physical computing allows us to build interactive physical systems by using software & hardware in order to sense and respond to the real world. C Programming for Arduino will show you how to harness powerful capabilities like sensing, feedbacks, programming and even wiring and developing your own autonomous systems. C Programming for Arduino contains everything you need to directly start wiring and coding your own electronic project. You'll learn C and how to code several types of firmware for your Arduino, and then move on to design small typical systems to understand how handling buttons, leds, LCD, network modules and much more. After running through C/C++ for the Arduino, you'll learn how to control your software by using real buttons and distance sensors and even discover how you can use your Arduino with the Processing framework so that they work in unison. Advanced coverage includes using Wi-Fi networks and batteries to make your Arduino-based hardware more mobile and flexible without wires. If you want to learn how to build your own electronic devices with powerful open-source technology, then this book is for you.
Table of Contents (21 chapters)
C Programming for Arduino
Credits
About the Author
Acknowledgement
About the Reviewers
www.PacktPub.com
Preface
Index

static, volatile, and const qualifiers


Qualifiers are the keywords that are used to change the processor's behavior considering the qualified variable. In reality, the compiler will use these qualifiers to change characteristics of the considered variables in the binary firmware produced. We are going to learn about three qualifiers: static, volatile, and const.

static

When you use the static qualifier for a variable inside a function, this makes the variable persistent between two calls of the function. Declaring a variable inside a function makes the variable, implicitly, local to the function as we just learned. It means only the function can know and use the variable. For instance:

int myGlobalVariable;

void setup(){
}

void loop(){
  myFunction(digitalPinValue);
}

void myFunction(argument){
int aLocalVariable;
aLocalVariable = aLocalVariable + argument;
  // playing with aLocalVariable
}

This variable is seen in the myFunction function only. But what happens after the first loop? The...