Programming Embedded Systems in C and C++

2 Chapter 1: Introduction

general-purpose computer is a blank slate; the manufacturer does not know what

the customer will do with it. One customer may use it for a network file server,

another may use it exclusively for playing games, and a third may use it to write

the next great American novel.

Frequently, an embedded system is a component within some larger system. For

example, modern cars and trucks contain many embedded systems. One embed-

ded system controls the anti-lock brakes, another monitors and controls the vehi-

cle’s emissions, and a third displays information on the dashboard. In some cases,

these embedded systems are connected by some sort of a communications net-

work, but that is certainly not a requirement.

At the possible risk of confusing you, it is important to point out that a general-

purpose computer is itself made up of numerous embedded systems. For exam-

ple, my computer consists of a keyboard, mouse, video card, modem, hard drive,

floppy drive, and sound card—each of which is an embedded system. Each of

these devices contains a processor and software and is designed to perform a spe-

cific function. For example, the modem is designed to send and receive digital

data over an analog telephone line. That’s it. And all of the other devices can be

summarized in a single sentence as well.

If an embedded system is designed well, the existence of the processor and soft-

ware ...