Thoth, a portable real-time operating system (Extended Abstract)

Microprocessors and Microsystems, 1990

explain the design decisions behind a new operating system to support MODULA-2 for automation software As in general soRware engineering, the increasing and unsatisfied demand for automation software has focussed attention towards the portability and reuse of software. In this context severe challenges are offered by soRware components with high quality requirements, such as the capability for multitasking, hard timing conditions, high (forecastable) reliability, as well as for components with direct access to hardware and system software. With the realtirne operating system XMod an attempt has been made to design such a system that is portable and, to a certain degree, independent of its environment. A portable software development methodology has been developed based on MODUtA-2. Using this approach it was possible to implement XMod for different microprocessor classes (Intel, Zilog) without extensive additional effort. A similar approach was used to develop high-level language device drivers and a high-level language symbolic realtime debugger. microsystems realtime operating systems MODULA-2

IEEE International Conference on Computer-Aided Design, 1998

Summary form only given. Embedded DSPs and CPUs are already commonplace in board-level systems and are becoming increasingly popular on systems-on-silicon. As embedded software grows in size and complexity, real-time operating systems [(RTOSs) are required to manage the embedded processor and ensure real-time response. This tutorial will introduce the attendee to real-time operating systems for embedded computing and their use in the design of embedded software. with both basic principles and advanced practice.

2001

This work was a grant to enhance the Maruti operating system in several ways, in order to provide Mississippi State with a platform upon which their work on the Real-Time Message Passing Interface could be developed. Key technical achievements: (1) Developed predictable Myrinet communications for use in a real-time NOW; (2) Developed the MSU-Kernel to provide a POSIX OS for real-time NOWs; (3) Developed and implemented an algorithm for deploying a globally synchronized clock in a real-time NOW; (4) Developed an improved real-time scheduler for the Maruti hard real-time operating system at University of Maryland (UMD); and (5) Introduced a new parametric approach in Maruti for dynamic scheduling at UMD. Details of the results of the work are presented in papers, thesis and project reports.

This article presents quantitative and qualitative results obtained from the analysis of real time operating systems (RTOS). The studied systems were Windows CE, QNX Neutrino, VxWorks, Linux and RTAI-Linux, which are largely used in industrial and academic environments. Windows XP was also analysed, as a reference for conventional non-real-time operating system, since such systems are also commonly and inadvertently used for instrumentation and control purposes. The evaluations include worst case response times for latency, latency jitter and response time.

2001

finished. It is possible to avoid the problem by adding break points to the event handling code where the handling of urgent events can take place. On the other hand, the problem is not critical, if a powerful processor is available. The real-time properties of most embedded systems are based on the use of real-time operating systems. Application of such operating systems requires high expertise and much time. The resulting software is often heavy and hard to maintain. In this paper we present a class of application specific operating systems called ReaGOS. ReaGOS is based on a new architecture and an operating principle, where the operating system calls application programs but not vice versa. The new architecture saves both data and code memory and it is fast enough for embedded systems. The operating system is generated automatically from a high level graphical specification. Another method uses interrupt mechanisms to handle I/O driver events [5]. This method has some disadvanta...

Proceedings Real-Time Technology and Applications Symposium, 1995

Distributed multimedia applications are typical of a new class of workstation applications that require realtime communication and computation services to be effective. Unfortunately, there remains a wide gap between the development of real-time computing technology in the research community and the deployment of real-time solutions in commercial systems. In this work we explore technology for allowing two operating systems, a general purpose operating system and a predictable real-time kernel, to co-exist on the same hardware. We discuss the problems of multiplexing shared devices and partitioning shared data structures to accommodate two operating systems, and present a CPU executive that allows the IBM Microkernel (a derivative of the Mach microkernel) with an OSF/1 server to co-exist with a simple real-time kernel we have built. We also extend the traditional theory of scheduling periodic tasks on a uniprocessor to accommodate the case where a real-time kernel is allocated only a fraction of the total CPU capacity.

Embedded Systems - Theory and Design Methodology, 2012

Real-Time Operating Systems and Programming Languages for Embedded Systems hardware architecture, as it is the case of RTSJ. This is undoubtedly a new scenario in the development of embedded real time systems. There is a wide range of hardware possibilities in the market (microcontrollers, microprocessors and DSPs); also there are many different programming languages, like C, C++, C#, Java, Ada; and there are more than forty real-time operating systems (RTOS) like RT-Linux, Windows Embedded or FreeRTOS. This chapter offers a road-map for the design of real-time embedded systems evaluating the pros and cons of the different programming languages and operating systems. Organization: This chapter is organized in the following way. Section 2 describes the main characteristics that a real-time operating system should have. Section 3 discusses the scope of some of the more well known RTOSs. Section 4 introduces the languages used for real-time programming and compares the main characteristics. Section 5 presents and compares different alternatives for the implementation of real-time Java. Finally, Section 6 concludes.

IFAC Proceedings Volumes, 1990

IFAC Proceedings Volumes, 1979

Two dedicated real-time operating systems (RTOS) are analysed and compared with logical model obtained in TC-8, Purdue Europe. Specialisation is mainly concentrated to Process Management, Exception Handling and operator-RTOS interface. It is concluded that dedicated RTOS, absolutely necessary in some cases, has in all applications certain advantag e s. Consequently, the possibility to dedicate an ope rating system should be considered as an essential RTOS design problem.

EURASIP Journal on Embedded Systems, 2008

The rapid progress in processor and sensor technology combined with the expanding diversity of application fields is placing enormous demands on the facilities that an embedded operating system must provide.