An embedded system is the use of a computer system built into a machine of some sort, usually to provide a means of control" (BCS Glossary of Computing and ICT). Embedded systems are everywhere in our lives, from the TV remote control to the microwave, to control the central heating to the digital alarm clock next to our bed. They are in cars, washing machines, cameras, drones and toys.
An embedded system has a microprocessor in it which is essentially a complete computer system with limited, specific functionality. As far as a user goes, they can usually interact with it through a limited interface. This typically will allow the user to input settings and make selections and also to receive output using text, video or audio signals, for example.
Characterisitcs of embedded systems
There are a number of common characteristics we can identify in embedded systems.
They are usually small, sometimes tiny and very light so they can be fitted into many products.
The computer system in an embedded system is usually a single microprocessor.
The microprocessor has been designed to do a limited number of very specific tasks in a product very quickly and efficiently.
The microprocessor can be mass-produced very cheaply.
They require a very tiny amount of power compared to a traditional computer.
They are very reliable because there are no moving parts.
Because the computer system is usually printed onto one board, if it does break down, you just swap the board; it is very easy to maintain.
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