Embedded SoPC Design with Nios II Processor and Verilog Examples

CHAPTER 1

OVERVIEW OF EMBEDDED SYSTEM

An embedded system is a special type of computer system. In this chapter, we examine the basic characteristics of an embedded system, highlight its differences from a general-purpose computer system, and introduce the concept and development flow of a “high-end” FPGA-based embedded system, which is the focus of this book.

1.1 INTRODUCTION

1.1.1 Definition of an embedded system

An embedded system (or embedded computer system) can be loosely defined as a computer system designed to perform one or a few specific tasks. The computer system is not the end product but a dedicated “embedded” part of a larger system that often includes additional electronic and mechanical parts. By contrast, a general-purpose computer system, such as a PC (personal computer), is a general computing platform and itself is the end product. It is designed to be flexible and to support a variety of end-user needs. Application programs are developed based on the available resource of the general-purpose computer system.

Since an embedded system is dedicated to specific tasks, its design can be optimized to reduce cost. A good design should contain just enough hardware resources to meet the application's required functionalities. On the other hand, a general-purpose computer system is expected to support a variety of needs and thus an application program is provided with a relatively abundant hardware resource. From this perspective, an embedded system can be thought of ...