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Embedded software is computer software, written to control machines or devices that are not typically thought of as computers. It is typically specialized for the particular hardware that it runs on and has time and memory constraints.〔(【引用サイトリンク】url=http://www.stroustrup.com/abstraction-and-machine.pdf )〕 This term is sometimes used interchangeably with firmware, although firmware can also be applied to ROM-based code on a computer, on top of which the OS runs, whereas embedded software is typically the only software on the device in question. A precise and stable characteristic feature is that no or not all functions of embedded software are initiated/controlled via a human interface, but through machine-interfaces instead.〔(【引用サイトリンク】url=http://www.ics-control.com )〕 Manufacturers 'build in' embedded software in the electronics in cars, telephones, modems, robots, appliances, toys, security systems, pacemakers, televisions and set-top boxes, and digital watches, for example.〔(【引用サイトリンク】url=http://www.computer.org/portal/web/certification/Embedded-Systems )〕 This software can be very simple, such as lighting controls running on an 8-bit microprocessor and a few kilobytes of memory with the suitable level of processing complexity determined with a Probably Approximately Correct Computation framework〔. 〕 (a methodology based on Randomized algorithms), or can become very sophisticated in applications such as airplanes, missiles, and process control systems.〔 http://ptolemy.eecs.berkeley.edu/publications/papers/02/embsoft/embsoftwre.pdf〕 ==Operating systems== Unlike standard computers that generally utilise a small number of operating systems (largely OS X, Windows and GNU/Linux), embedded software comes in a wide variety of operating systems, typically a real-time operating system. This runs from small one-person operations consisting of a run loop and a timer, to LynxOS, VxWorks, BeRTOS, ThreadX, to Windows CE or Linux (with patched kernel). Others include OpenWrt, PikeOS, eCos, Fusion RTOS, Nucleus RTOS, RTEMS, INTEGRITY, uC/OS, QNX, FreeBSD and OSE. Code is typically written in C or C++. Ada is used in some military and aviation projects. 抄文引用元・出典: フリー百科事典『 ウィキペディア(Wikipedia)』 ■ウィキペディアで「embedded software」の詳細全文を読む スポンサード リンク
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