The RTEMS Project

What is RTEMS? RTEMS is an open source Real Time Operating System (RTOS) that supports open standard application programming interfaces (API) such as POSIX. RTEMS stands for Real-Time Executive for Multiprocessor Systems. It is used in space flight, medical, networking and many more embedded devices. RTEMS currently supports 18 processor architectures and approximately 200 Board support packages.

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Supported by the community

Need help? Our strong community of users and developers are always around to answer questions

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Flexible deployment options

Choose how you deploy RTEMS within your company or organisation

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Open Development

We host our own GitLab, Mailing lists and you can find us on Discord

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You are in control

The entire RTEMS development cycle is public with all source. Long term maintenance is made easy and reliable.

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30 years

RTEMS has been an open source project for 30 years. Long term support. Long term availability.

Development site
Build where you need

RTEMS actively maintains a working toolchain for Windows, Linux, OS X and FreeBSD

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Features

RTEMS comes with a complete set of features to help you with your application.

Kernel

  • Multitasking capabilities
  • Homogeneous and heterogeneous multiprocessor systems
  • Event-driven, priority-based pre-emptive scheduling
  • Optional rate-monotonic scheduling
  • Intertask communication and synchronization
  • Priority inheritance
  • Responsive interrupt management
  • Dynamic memory allocation
  • High level of user configurability
  • Portable to many target environments

API

  • POSIX 1003.1b API including threads
  • RTEID/ORKID based Classic API (similar to pSOS+) from the VMEbus Industry Trade Association.
  • TCP/IP including BSD Sockets
  • uITRON 3.0 API
  • GNU Toolset Supports Multiple Language Standards
  • ISO/ANSI C
  • ISO/ANSI C++ including Standard Template Library
  • Ada with GNAT/RTEMS

Networking

  • High performance port of FreeBSD TCP/IP stack
  • UDP
  • ICMP
  • TCP
  • DHCP
  • RARP
  • BOOTP
  • PPP

Device Driver

  • Block Device Cache
  • Device Only File System
  • ATA Block Driver

File System

  • In-memory Filesystem (IMFS)
  • Mini-IMFS (reduced services and footprint)
  • Device File System (lowest memory Filesystem, devices only)
  • MS-DOS FAT32
  • MS-DOS FAT16
  • MS-DOS FAT12
  • RTEMS File System (RFS)
  • TFTP client Filesystem
  • NFS client

Block Devices

  • ATA Disk Drives
  • RAM Disk
  • Volatile Disk
  • Flash Disk
  • SPI SD Card

Debugging

  • GNU debugger (gdb)
  • DDD GUI interface to gdb
  • Thread aware
  • Debug over Ethernet
  • Debug over serial port

Clients

  • Domain Name Service (DNS) client
  • Trivial FTP (TFTP) client
  • Network Filesystem System (NFS) client

Servers

  • FTP server (FTPD)
  • Web Server (HTTPD)
  • Telnet Server (Telnetd)
  • Sun Remote Procedure Call (RPC)
  • Sun eXternal Data Representation (XDR)
  • CORBA
  • PPPD

Latest News

New RTEMS website

  • October 20, 2024

    • Welcome to the new RTEMS Website using Hugo and Tailwind. Source available soon.

    More news...