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About eCos


eCos is provided as an open source runtime system supported by the GNU open source development tools. Developers have full and unfettered access to all aspects of the runtime system. No parts of it are proprietary or hidden, and you are at liberty to examine, add to, and modify the code as you deem necessary. These rights are granted to you and protected by the eCos license. It also grants you the right to freely develop and distribute applications based on eCos. We welcome all contributions back to eCos such as board ports, device drivers and other components, as this helps the growth and development of eCos, and is of benefit to the entire eCos community.

One of the key technological innovations in eCos is the configuration system. The configuration system allows the application writer to impose their requirements on the run-time components, both in terms of their functionality and implementation, whereas traditionally the operating system has constrained the application's own implementation. Essentially, this enables eCos developers to create their own application-specific operating system and makes eCos suitable for a wide range of embedded uses. Configuration also ensures that the resource footprint of eCos is minimized as all unnecessary functionality and features are removed. The configuration system also presents eCos as a component architecture. This provides a standardized mechanism for component suppliers to extend the functionality of eCos and allows applications to be built from a wide set of optional configurable run-time components. Components can be provided from a variety of sources including the standard eCos release, commercial third party developers and open source contributors.

The royalty-free nature of eCos means that you can develop and deploy your application using the standard eCos release without incurring any royalty charges. In addition, there are no up-front license charges for the eCos runtime source code and associated tools. eCos delivers, without charge, everything necessary for basic embedded applications development.

eCos is designed to be portable to a wide range of target architectures and target platforms including 16, 32, and 64 bit architectures, MPUs, MCUs and DSPs. The eCos kernel, libraries and runtime components are layered on the Hardware Abstraction Layer (HAL), and thus will run on any target once the HAL and relevant device drivers have been ported to the target's processor architecture and board. Currently eCos supports 13 different target architectures:

  • 68K/ColdFire
  • ARM (including ARM7TDMI, ARM9TDMI, Cortex-M, StrongARM, XScale)
  • CalmRISC16 and CalmRISC32 (RedBoot only)
  • Fujitsu FR-V
  • Fujitsu FR30
  • Hitachi H8/300
  • Intel x86
  • Matsushita AM3x
  • MIPS
  • NEC V8xx
  • PowerPC
  • SuperH

Support includes many of the popular variants of these architectures and evaluation boards. Many new ports are in development and will be released as they become available.

eCos has been designed to support applications with real-time requirements, providing features such as full preemptability, minimal interrupt latencies, and all the necessary synchronization primitives, scheduling policies, and interrupt handling mechanisms needed for these type of applications. eCos also provides all the functionality required for general embedded application support including device drivers, memory management, exception handling, C, math libraries, etc. In addition to runtime support, the eCos system includes all the tools necessary to develop embedded applications, including eCos software configuration and build tools, and GNU based compilers, assemblers, linkers, debuggers, and simulators.

The following core functionality is provided:

  • Hardware Abstraction Layer (HAL)
  • Real-time kernel
    • Interrupt handling
    • Exception handling
    • Choice of schedulers
    • Thread support
    • Rich set of synchronization primitives
    • Timers, counters and alarms
    • Choice of memory allocators
    • Debug and instrumentation support
  • µITRON 3.0 compatible API
  • POSIX compatible API
  • ISO C and math libraries
  • Serial, ethernet, SPI, I2C, framebuffer, CAN, ADC, wallclock and watchdog device drivers
  • USB slave support
  • TCP/IP networking stacks
  • C++ Standard Template Library (uSTL)
  • GDB debug support

System requirements

The eCos net distribution is available in both Linux and Windows versions. The Linux version is tested under recent versions of the Fedora, openSUSE and Ubuntu distributions for x86 and should work under most Linux variants. The Windows version has been tested under Microsoft Windows 2000 Professional, Windows XP and Windows Vista. It should also work under Windows NT4 with SP6a. The use of eCos under Windows 95/98/ME is no-longer supported.

The eCos net distribution is supplied with full support for configuration of eCos on all host platforms via both a graphical configuration tool and a command-line tool. It is intended to be used in conjunction with GNU development tools which are available freely on the net. As a minimum, the gcc compiler, gdb debugger and binutils tools are required to build eCos, link with application code and undertake debugging.