Embedded systems

An embedded system is a special purpose computer system designed to perform one or a few specific functions. The main difference between embedded systems and a general-purpose computer is that the computer can do many different tasks depending on programming. Since embedded systems are dedicated to specific tasks, engineers can optimize it, increasing the performance and reliability.

Embedded systems range from small digital devices such as portable video players, to big factory controllers; and its complexity varies from low, controlled with a single microcontroller to very complex systems with multiple processors and units.

The term "Embedded System" is not totally defined, some devices are not embedded systems such as handheld computers; however they share some elements with embedded systems- such as the operating system and micro processors.

History

In the first years if computers in the 1930-40's, computer were dedicated to a single task, but were far too large and expensive for most kinds of tasks performed by embedded computers of today.

One of the first embedded systems we can mention was the Apollo Guidance Computer, developed at the MIT Instrumentation Laboratory. Another early mass-produced embedded system was the Autonetics D-17 guidance computer of the minuteman missile, released in 1961.  It was build from transistor logic and had a hard disk for main memory.

Since theses early applications, embedded systems have come down in price and they had increased enormously in processing, low power and functionality. Through the years the cost of microprocessors and controllers has fell thus it became easy to replace expensive knob-based analog components such as potentiometers and variable capacitors with up/down buttons or knobs.

The integration of microprocessors and microcontrollers has further increased the application for which embedded systems are used into areas where traditionally a computer would not have been considered. The embedded systems are usually more complex than a traditional solution, most of the complexity is in the hardware and very few additional components may be need and most of the design effort is in the software.