An embedded system is a type of computer that can perform a few specialised tasks. This design is contrary to the normal computer that is designed to perform a number of operations that are in many cases unrelated to each other. Embedded systems are present in many of the devices that are used today and act as their control units. The main issue with embedded systems is their optimality in the terms of cost, space and power consumption etc. as, there is no focus on increasing the functionality of the device. The term embedded system can thus, be used to refer to devices that perform certain specific functions and cannot be used to perform others by loading applications on them.
Here are a few characteristic features of embedded systems:
- Many of the embedded systems have several hardware restraints as they have to process real time inputs and must also be safe to use. Others may not have some of these constraints and thus, reduction in the cost of the hardware used is possible.
- The term embedded system does not refer to devices that are isolated but rather, they are a part of the device they control or perform some other task in.
- The software that is used in embedded systems is usually termed as firmware. The same is stored in disk drives or in ROMs as an embedded system usually lacks a full-fledged hard disk drive.
Embedded systems many times do not have a user interface as they are designed to perform only a single task. Whereas, some other devices similar to embedded systems such as PDA have a complete user-friendly interface.
The simple embedded systems usually consist of components such as buttons and LED to input the data and to show the output respectively. On the other hand, complex embedded systems have touch screens, large amount of buttons etc. for the purposes of input, output etc. In order to accommodate this large amount of buttons, they are usually placed at the edge of the screen.
Engineers have successfully made use of the internet in order to provide individuals with and interface to remote embedded systems. Thus, a single system can be used by many users at different locations.
In general, embedded systems can be classified into two types viz. microprocessors and microcontrollers. Microprocessors usually perform a single or very limited set of tasks. In many cases, a single microprocessor may not be of any use at all. Microcontrollers on the other hand can perform a number of operations and thus, can execute a complete task. They can be considered as extended versions of a microprocessor.
Microprocessors are used in various different areas of technology. For example, they are present in the cellular phones that we use. They are also used in mp3 players, refrigerators, microwaves, some remote controls, printing devices, GPS receivers etc.
Thus, embedded systems have become indispensable in today’s world and daily human activity (as it is today) without them, is practically impossible.