High-level Real-time Language Research Articles

76 Lifestyle factors influence in the frequency in buccal micronucleus

The requirements to be fulfilled by languages in hard real-time environments, and corresponding language constructs necessitated by them, are summarised. Aimed towards enabling the production of reliable software for time-critical applications, the syntax and semantics of appropriate extensions of the high-level real-time language PEARL are described, mainly providing the following features: application oriented resource synchronisation with time-out and inherent deadlock prevention; constructs to express the exact time behaviour of tasks and to survey the occurrence and sequence of events; support of due dates observing task scheduling algorithms allowing the early detection and handling of overload conditions; accurate timing of operations; and application oriented simulation regarding the operating system overhead for software verification purposes. Finally, the operating system functions required by the proposed language elements and verification tools are outlined, and it is reported, to which extend and how they are already provided by the PEARL oriented real-time operating system PORTOS.

7 Signalling via the ALK receptor tyrosine kinase – insights from the fruitfly

The requirements to be fulfilled by languages in hard real-time environments, and corresponding language constructs necessitated by them, are summarised. Aimed towards enabling the production of reliable software for time-critical applications, the syntax and semantics of appropriate extensions of the high-level real-time language PEARL are described, mainly providing the following features: application oriented resource synchronisation with time-out and inherent deadlock prevention; constructs to express the exact time behaviour of tasks and to survey the occurrence and sequence of events; support of due dates observing task scheduling algorithms allowing the early detection and handling of overload conditions; accurate timing of operations; and application oriented simulation regarding the operating system overhead for software verification purposes. Finally, the operating system functions required by the proposed language elements and verification tools are outlined, and it is reported, to which extend and how they are already provided by the PEARL oriented real-time operating system PORTOS.

Implementation of Hard Real-Time Embedded Control Systems

Although the domain of hard real-time systems has been thoroughly elaborated in the academic sphere, embedded computer control systems –- being an important component in mechatronic designs –- are seldom dealt with consistently. Often, off-the-shelf computer systems are used, with no guarantee that they will be able to meet the requirements specified. In this paper, a design for embedded control systems is presented. Particularly, the paper deals with the hardware architecture and design details, the operating system, and high-level real-time language support. It is shown how estimates of process run-times necessary for schedulability analysis can be acquired on the basis of deterministic behavior of the hardware platform.

Recommendations for a Real Time Systems Curriculum

An outline of a syllabus for the education of real time systems engineers is given. This comprises the treatment of basic concepts, real time software engineering and programming in high level real time languages, real time operating systems with special emphasis to such topics as task scheduling, hardware architectures and especially distributed automation structures, process interfacing, system reliability and fault tolerance, and finally integrated project development support systems. Accompanying course material and laboratory work are outlined, such as suggestions for establishing a laboratory with advanced, but low-cost, hardware and software are provided.

A Language for Complex Real-Time Systems

The new generation of real-time systems are characterized by multiple, conflicting non-functional desiderata on goals. Furthermore, the systems exhibit very large size and complexity-in both application structures and underlying software and hardware platforms. We argue that current high-level real-time languages do not meet the challenge of these complex real-time systems and introduce a new language-CRL-that we claim does. Relevant real-time features of CRL are discussed and a summary is provided vis-a-vis future features that would address non-functional goals other than timeliness. A current implementation status and how CRL fits into a rather ambitious environment for the construction of complex real-time systems (under construction in our Real-Time Computing Lab at NJIT) are briefly presented.

Comparative evaluation of high-level real-time programming languages

Owing to the fast growing need for better means of building real-time systems, a number of representative languages used in real-time programming is surveyed. The evaluation focuses on seven languages which possess explicit real-time features. Based on a categorization of the latter, the seven languages are then compared with respect to their real-time capabilities. The strong points and the limitations of Ada and PEARL, the only high-level real-time languages readily applicable in industrial control environments, are covered in more detail. The evaluation reveals that none of the languages actually used in industry is genuinely real-time. Therefore, a number of new features is suggested for incorporation into existing or future languages and their run-time environments. These proposals are meant to advance the inadequate state of affairs, and also to reignite the discussion of this topic in the real-time community.

A curriculum for real-time computer and control systems engineering

An outline of a syllabus for the education of real-time-systems engineers is given. This comprises the treatment of basic concepts, real-time software engineering, and programming in high-level real-time languages, real-time operating systems with special emphasis on such topics as task scheduling, hardware architectures, and especially distributed automation structures, process interfacing, system reliability and fault-tolerance, and integrated project development support systems. Accompanying course material and laboratory work are outlined, and suggestions for establishing a laboratory with advanced, but low-cost, hardware and software are provided. How the curriculum can be extended into a second semester is discussed, and areas for possible graduate research are listed. The suitable selection of a high-level real-time language and supporting operating system for teaching purposes is considered.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Education of real-time systems engineers

An outline of a syllabus for the education of real-time systems engineers is given. This comprises the treatment of basic concepts, real-time software engineering and programming in high-level real-time languages, real-time operating systems with special emphasis to some topics like task scheduling, hardware architectures and especially distributed automation structures, process interfacing, system reliability and fault-tolerance, and finally integrated project development support systems. Accompanying course materials and laboratory work are outlined and suggestions for establishing a laboratory with very advanced, but low-cost, hardware and software are provided. It is described how the curriculum can be extended into a second semester and areas for possible graduate research are listed. The paper closes with considerations about a suitable selection of a high-level real-time language and a supporting operating system for teaching purposes.

Additional pearl language structures for the implementation of reliable and inherently safe real-time systems

The requirements to be fulfilled by languages in hard real-time environments, and corresponding language constructs necessitated by them, are summarised. Aimed towards enabling the production of reliable software for time-critical applications, the syntax and semantics of appropriate extensions of the high-level real-time language PEARL are described, mainly providing the following features: application oriented resource synchronisation with time-out and inherent deadlock prevention; constructs to express the exact time behaviour of tasks and to survey the occurrence and sequence of events; support of due dates observing task scheduling algorithms allowing the early detection and handling of overload conditions; accurate timing of operations; and application oriented simulation regarding the operating system overhead for software verification purposes. Finally, the operating system functions required by the proposed language elements and verification tools are outlined, and it is reported, to which extend and how they are already provided by the PEARL oriented real-time operating system PORTOS.

A Debugging Package for Modula

A debugging package for use in real-time with the programming language Modula is presented. The authors argue that such a package has some generality and portability in the context of modern high-level realtime languages. The facilities provided by the package, which are at a low level, and their implementation are described. These facilities include a journal, event counting, and event marking. The package has been in use for over one year and some conclusions from this use are presented. However, problems have arisen from the low level and flexible nature of the facilities and these are discussed. Finally, some execution times for the facilities are listed and ideas for future work given.

Towards The Standardization of Real-Time Operating System Kernels

Much attention has been paid to the development of high level Real-time languages these last ten years. In the expectation of a universal Real-time language (will it be Ada?), engineers may have to adopt a suitable methodology involving standard interfaces. As the tasking interface is the keystone of any Real-time operating system, we develop guide lines which may facilitate the evaluation of existing proposals or the creation of a new standard Real-time tasking interface. We analyse the existing proposals in the light of these guidelines and we set up a synthesis, present state of the BNI1 project SCEPTRE whose aim is to define a french common Real-time tasking interface.