Programming Embedded Systems in C and C++

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Chapter 9

In this chapter:

• Application Overview

• Flashing the LED

• Printing “Hello,

World!”

• Working with Serial

Ports

• The Zilog 85230

Serial Controller

9

Putting It All

Together

9.

A sufficiently high level of technology is

indistinguishable from magic.

—Arthur C. Clarke

In this chapter, I’ll attempt to bring all of the elements we’ve discussed so far

together into a complete embedded application. I don’t have much new material

to add to the discussion at this point, so the body of the chapter is mainly a

description of the code presented herein. My goal is to describe the structure of

this application and its source code in such a way that there is no magic remaining

for you. You should leave this chapter with a complete understanding of the exam-

ple program and the ability to develop useful embedded applications of your own.

Application Overview

The application we’re going to discuss is not much more complicated than the

“Hello, World!” example found in most other programming books. It is a testa-

ment to the complexity of embedded software development that this example

comes near the end of this book, rather than at its beginning. We’ve had to gradu-

ally build our way up to the computing platform that most books, and even high-

level language compilers, take for granted.

Once you’re able to write the “Hello, World!” program, your embedded platform

starts to look a lot like any other programming ...