Real-Time Operating Systems

• Alpha Kernel (Carnegie Mellon University) Group Members
• C Executive and PSX (JMI Software Systems)
  C EXECUTIVE is a operating system kernel for embedded applications - providing a small, efficient, real-time software environment for programs written in C. C EXECUTIVE, as small as 5 KB in ROM space, is available on 8-, 16- and 32-bit CISC and RISC processors, providing the foundation for a common, corporate-wide, portable software strategy. PSX provides a single-user, single-group, subset of POSIX.1, with up to 32,000 preconfigured processes. PSX adds a substantial subset of the POSIX.1 system calls to the basic C EXECUTIVE kernel. Using these calls allows applications to migrate from POSIX-conformant UNIX platforms to board-level systems, or vice versa.
• Chimera (Carnegie Mellon University)
  The Advanced Manipulators Laboratory, at Carnegie Mellon University, has developed the Chimera Real-Time Operating System, a next generation multiprocessor real-time operating system (RTOS) designed especially to support the development of dynamically reconfigurable software for robotic and automation systems. Version 3.0 and later of the software is already being used by several institutions outside of Carnegie Mellon, including university, government, and industrial research labs.
• Harmony (National Research Council of Canada)
  Harmony is a multitasking, multiprocessing operating system for realtime control, developed at the National Research Council to serve a need for a flexible system for realtime control of robotics experiments and for other applications of embedded systems where predictable temporal performance is a requirement. Harmony is extensible, configurable and portable, both across different target computers (typically assembled from single-board computers), and across different development hosts.
• Helios (Perihelion Distributed Software)
  Helios is a micro kernel operating system for embedded and multiprocessor systems. The operating system is modular in design and can scale from an embedded runtime executive up to a fully distributed operating system.
• ITRON
  ITRON (industrial TRON) is a real-time operating system specification for embedded systems. Many products have been developed based on the ITRON specifications. ITRON is a de-fact standard operating system specification in Japan for consumer applications.
• KeyKOS
  KeyKOS is an operating environment for S/370 computers which provides a high level of security, reliability, performance, and productivity. It allows emulation of other environnzens such as VM, MVS, and POSIX. Development of KeyKOS ceased in 1990. Many of the ideas of this system have been carried forward into EROS
• Lynx (Lynx Real-time Systems)
  LynxOS is a proprietary UNIX-like real-time operating system. LynxOS looks and feels like UNIX from the user/programmer point of view. It was developed from the ground-up with high performance, deterministic hard real-time response in mind. Although LynxOS is conformant with POSIX 1003.1 it is not derived from any AT&T/USL/Novell source code. The OS is in effect a complete re-implementation of UNIX from a real-time perspective.
• Maruti (University of Maryland) Group Members
  Maruti is a time-based operating system research project at the University of Maryland. With Maruti 3.0, we are entering a new phase of our project. We have an operating system suitable for field use by a wider range of users, and we are embarking on the integration of our time-based, hard real-time technology with industry standards and more traditional event-based soft- and non-real-time systems.
• MTOS
• OS9 (Microware Systems Corporation)
  OS-9 is a real-time, multiuser, multitasking operating system developed by Microware Systems Corporation. It is modular, allowing new devices to be added to the system simply by writing new device drivers, ]or if a similar device already exists, by simply creating a new device descriptor. All I/O devices can be treated as files, which unifies the I/O system. In addition, the kernel and all user programs are ROMable.
• OSE
  OSE is a full-featured family of high quality, reliable and high performance real-time operating systems from Enea OSE Systems, Sweeden. There is an OSE kernel for every need, from OSE Basic (for Z80, i8051 and others) up to OSE Delta (for M68k, PPC and others). OSE Delta is also the first RTOS to be certified according to the software quality standard IEC 1508. OSE Delta supports runtime configuation, runtime program loading, multi-CPU systems and TCP/IP.
• QNX
  A micro-kernel, distributed, real-time, fault-tolerant, POSIX-certified OS for the x86. QNX adopts the approach of implementing an OS with a 10 Kbyte micro-kernel surrounded by a team of optional processes that provide higher-level OS services. QNX is fully distributed, with all system interfaces network transparent. QNX has successfully been used in tiny ROM-based embedded systems and in several-hundred node distributed systems.
• Roadrunner
  In traditional operating systems, input/output (I/O) subsystems implement a push-pull environment that provides system calls to allow user applications to pull data from or push data to a device. An important set of applications make combined use of push-pull to implement simple streaming, i. e. data is moved from one device to another with no transformations. Using push-pull I/O to implement these applications does not provide maximum performance. This work proposes a kernel design optimized for simple streaming applications. The Roadrunner operating system is being developed specifically to implement multiple, concurrent, high-speed speed data streams with Quality-of-Service (QOS) parameters.
• Real-Time Mach Project (Carnegie Mellon University) Group Members
  Related to: Mach
  Real-Time Mach is a research prototype real-time operating system intended for use as a vehicle for doing real-time systems research. The system is being developed by the ART Project in the School of Computer Science, Carnegie Mellon University.
• RTEMS (Redstone Military Arsenal)
  RTEMS is a real-time operating system for embedded computer systems with the following features:
  • support for homogeneous and heterogeneous multiprocessor systems
  • event-driven, priority-based, preemptive scheduling
  • optional rate monotonic scheduling
  • intertask communication and synchronization
  • responsive interrupt management
  • dynamic memory allocation
• RTMX O/S
  Group Members: RTMX Incorporated
  RTMX is a commercial, BSD 4.4-derived, real-time system that offers POSIX 1003.4 real-time programming support with user tunability along with the standard UNIX functionality of BSD networking, X windows, and a full C development environment.
• RTX
  Group Members: Mike Podanoffsky
  RTX is a very small, very fast real time executive that utilizes signals and queuing as a basis for managing and scheduling tasks. It becomes very easy to support multiple processors, communication channels, and to synchronize processes. RTX is completely free, but it is not public-domain software. If you decide to use the software, you may receive an automatic license to do so even in commercial products, if you provide adequate, reasonable credit to its developer.
• Spring Real-Time Project (University of Massachsetts, Amherst) Group Members
  The Spring kernel has been designed and implemented to support/provide predictability, on-line dynamic guarantees, atomic guarantees, end-to-end scheduling and resource reservations. It utilizes a micro-kernel design for multiprocessor architectures and provides an interface to remote processes, support for distributed shared memory, and predictable low level communication. The kernel exists as a component of Spring's integrated environment. This environment extracts significant semantic information and this information is used at runtime to support flexibility. (ed: This is not the same as the Spring OS from Sun, which unfortunately has the same name.)
• Sumo (Lancaster University)
  Related to: Chorus
  Over the past few years members of the SUMO team have been designing and implementing a microkernel based system with facilities to support distributed real-time and multimedia applications and ODP based multimedia distributed application platforms. We are interested in both communications and processing support for distributed real-time/ multimedia applications in end systems, and believe that such applications require thread-to-thread real-time support according to user supplied quality of service (QoS) parameters.
• VxWorks (Wind River Systems)
  VxWorks(R) is the premier development and execution environment for complex real-time and embedded applications on a wide variety of target processors. Three highly integrated components are included with VxWorks: a high performance scalable real-time operating system which executes on a target processor; a set of powerful cross-development tools which are used on a host development system; and a full range of communications software options such as Ethernet or serial line for the target connection to the host.