Definition[]
Embedded systems are specialized computer systems that are part of a larger system or machine.[1]
An embedded system is
| “ | [a] system that performs or controls a function, either in whole or in part, as an integral element of a larger system or subsystem.[2] | ” |
Overview[]
An embedded system may be thought of as a special-purpose computer system, which is completely encapsulated by the device it controls. It is often designed to perform dedicated functions and subject to resource-limitation constraints as part of a mechanical device.
Often embedded system programs are implemented in read-only memory and are not intended to be generally reprogrammable. (In contrast, general-purpose computing systems, such as PCs, execute a wide variety of functions and are easily reprogrammed.) Most embedded systems use a mix of various firmware items that supplement the software running on the volatile memory portion of the system.
Virtually all appliances that have a digital interface — for example, watches, microwaves, video cassette recorders (VCR), digital video disc (DVD) players, and cars — utilize embedded systems.
Some embedded systems include an operating system, but many are so specialized that the entire logic can be implemented as a single program.
References[]
- ↑ Technology Assessment: Cybersecurity for Critical Infrastructure Protection, at 141.
- ↑ Department of Defense, National Computer Security Center, Glossary of Computer Security Terms (NCSC-TG-004, Ver. 1) (Oct. 21, 1988).