Wolfram Donat - Jumpstarting C: Learn the All-Purpose Programming Language for Microcontrollers and Computers

Copyright 2017. Wolfram Donat. All rights reserved.

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December 2017: First Edition

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2017-12-13 First Release

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A sk almost any computer hardware or software engineer which programming language she learned first, and the answer is bound to be C or C++. Many computer scientists start with Java or Cs stepchild, C#, but engineers normally learn C. Its the best way, after all, to get into the basics of algorithms and operating systems. The Windows, Mac, and Linux kernels, after all, are all written mostly in C. Aside from assembly, its probably one of the most basic programming languages.

C is powerful, fast, and unsexy. Its got built-in errors you may have never heard of (What the hell is a segmentation fault?!) and lets you mess with actual memory heaps and registers. There are no classes or even stringsyoure dealing with character arrays here, folks. Theres no fancy garbage collection if you use some memory for an array, youll probably want to free up that memory when youre done, or youll have a memory leak that could crash your program later.

C is cross-platform, but not in the same way that Python is cross-platform. Python code written on a Linux box can, with a few exceptions, run on a Windows machine without alterations. Most C written on a Linux computer will run on a Windows computer, but it will need to be recompiled first. C executables are specific to the machine on which theyre compiled, and transferring between operating systems can pose some unique challenges.

If you take the time to learn C (and its big brother, C++), your programming will benefit, even if youre already an experienced Python, Java, or even web programmer. Programming in C brings you back to basics, doesnt let you cut corners, and truly makes you think about what youre trying to do and the best way to do it. Yes, it can be incredibly frustratingI have lost literally hours trying to debug a piece of code, only to find it was merely missing one semicolonbut it can also be quite rewarding. Theres something about programming close to the metal that reminds me why I became a computer engineer in the first place.

Im assuming that you, the reader, bring the following to this book:

• A computer, and the ability to access the Internet
• Some knowledge of programming, even very basic
• A Raspberry Pi Zero or Zero W and all assorted cables
• Some LEDs, resistors, a breadboard, and some jumper wires

So if youre wanting to expand your horizons, and learn some new languages and some new skills, follow along and Ill teach you some C!

Chapter 1
Installing the Required Bits and Pieces

I n this chapter, youll learn about C and C++ IDEs and compilers, and Ill walk you through the process of installing them on your favorite computer. Be warned, however, that the projects in chapters 3 and 4 will be running on a Raspberry Pi Zero, which is a Linux-based system.

If you already have a Pi Zero or another Linux machine, I recommend you set it up now. The basic programs that well go through in chapters 1 and 2 will run on any system, but if youre already familiar with Linux and the Pi, so much the better.

If youd like to get started learning with Linux but dont have a computer on which to install it, I suggest you check out VirtualBox (http://www.virtualbox.org) from Oracle. VirtualBox is free and lets you install almost any client operating system (Windows, Linux, and a few others) onto a virtual computer running inside your host machine (Windows, Mac, or Linux). Since everything is free, you can download VirtualBox for your current computer, download a free Linux version (Ubuntu is probably the most popular, but you have many to choose from), start up your new virtual computer, and follow along with this book.