Simple Embedded Linux System
by Vincent Sanders and Daniel Silverstone
Introduction
Constructing an embedded system with Linux is often seen as a complex undertaking. This article is the first in a series which will show the fundamental aspects of constructing such systems and enable the reader to apply this knowledge to their specific situation.
This first article covers the construction of the most basic system possible, which will provide a command shell on the console. Along with the rest of the series, it assumes a basic understanding of a Linux-based operating system. While discussing concepts and general approaches, these concepts are demonstrated with extensive practical examples. All the practical examples are based upon a Debian- or Ubuntu-based distribution.
What is an embedded system?
The term “Embedded System” has been applied to such a large number of systems that its meaning has become somewhat ill-defined. The term has been applied to everything from 4-bit microcontroller systems to huge industrial control systems.
The context in which we are using the term here is to refer to systems where the user is limited to a specific range of interaction with a limited number of applications (typically one). Thus, from the whole spectrum of applications which a general purpose computer can run, a very narrow selection is made by the creator of the embedded system software.