The original EMBEDDED topic has been moved to TARGET Embedded (Embedded Systems without OS)
An embedded system is a computer system designed to perform one or a few dedicated functions, often with real-time computing constraints. It is embedded as part of a complete device often including hardware and mechanical parts.
In contrast, a general-purpose computer (such as a PC), is designed to be flexible and to meet a wide range of end-user needs. Embedded systems control many devices in common use today. See Wikipedia:Embedded System for further description.
As general purpose systems (PCs) are becoming smaller and smaller and embedded systems become more and more powerful (and universally usable devices), the border between embedded systems and general purpose computers will blur in future. Also a point of discussion would be to which section smart phones will end up.
We can divide embedded systems into several sections:
Embedded systems without general purpose operating system (OS)
For these devices, a special target in FPC exists TARGET Embedded
For thes devices, special targets exist in FPC. Also there exist specially built crosscompilers for the X86 Windows platform:
- Gameboy Advance (OS_TARGET=gba CPU_TARGET=arm BINUTILSPREFIX=arm-eabi)
- Main processor: ARM7tdmi)
- Sub processor: Z80 arm-gba-fpc-2.4.2.i386-win32.zip
- Nitendo DS (OS_TARGET=nds CPU_TARGET=arm BINUTILSPREFIX=arm-eabi)
- Main processor: ARM946E-S (67 MHz, in DSi: 133 MHz)
- Sub processor: ARM7TDMI (33 MHz) arm-nds-fpc-2.4.2.i386-win32.zip
Embedded systems with a general purpose operating system
There are several operating systems commonly used in embedded systems
Here several flavours exist: From (slightly to radical) slimmed down desktop Linux distributions (like Debian) to even slimmer variants consisting of a Linux kernel and some compact tools packages like BusyBox. Other variants like:
- Open RTLinux aim on enhancements of the real-time behaviour.
- ARM Linux Embedded Systems
- i386 Linux Embedded Systems
Here we have XPe (Windows XP Embedded) which behaves mostly like its desktop counterpart (i386 only) but offers the following benefits:
- System Builder allows to include/exclude components to slim down the system
- Readonly Filesystems supported for more robust operation
- Licensing done in System Builder; no individual licensing at product rollout
The successor is <please add>
Another other branch is Windows-Mobile/Windows CE family of operating systems.
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