Amir A. Khwaja

Syntax-directed editing environments: issues and features

Syntax-directed editing etrviraRwwnt.r are designed for the develqwtent and maintenance offormal documents such as specification, comptter programs, and structured s@vare documentation. The purpose of sttch environments is to provide a variety of facilities for the conrtructwn of the fnvnal documents in an integrated ad eq to use manner. Based on this premise, the paper identi~ the usability and design of syntax-directed editing environments tar critical issues and investigates the factors contributing to thsse issues. A number of features are formulated for the &sign andor the use of such environments. Sc.vne ~ the existing editing environments are analyzed wing theformtdated features and theresult of the anatysis is presented in a tabular fashion.

Multiple views of an executable software specification language

Abstract The front end of the software life cycle has been identified as critical in the development of software systems. The development of precise, concise, and unambiguous software specifications is the important link in the front end of the software life cycle. Executable software specification languages have been developed for prototyping as a means of demonstrating functionality. The executable specifications can serve to validate end-user needs. In addition, the executable specifications can also serve as the standard for activities downstream in the software life cycle, e.g., design validation, test data generation, and software enhancements. The iterative development process puts stringent requirements on the usability of the tools and techniques in the front end of the software life cycle. The DESCARTES specification language and support software were developed to address these issues. The DESCARTES language is a simple yet powerful approach to the specification of software systems. A language processor with an abstract execution facility allows for execution of partial through complete DESCARTES specifications. This article discusses the usability of DESCARTES in the context of evaluation criteria proposed by several specification language developers. Presented here are approaches to enhance usability in terms of providing multiple views and editing of DESCARTES specifications and using these views in an integrated fashion. Textual, graphical, and Nassi-Shneiderman representations are described for DESCARTES specifications. The DESCARTES Visual Support Environment is presented as the means for providing the multiple views.

A property based specification formalism classification

Specification formalisms may be classified through some common properties. Specification formalism classification may be used as a basis for the evaluation of the adequacy of formal specification languages within specific application domains. System modelers may use this classification to determine if the system modeling requirements can be met by a particular class of specification formalism. This paper evaluates existing specification formalism classification approaches by various researchers and highlights certain observations regarding the suggested classification schemes. The paper then proposes a specification formalism classification method using specification language properties. The proposed classification approach, loosely following the prototype theory for classification, maps specification language properties to specification formalisms and determines which language properties can best be achieved by different formalisms.

Adaptation and modification of Nassi-Shneiderman charts to represent Descartes specifications visually

Descartes is an executable specification language that supports the rapid prototyping of partial through complete software specifications. A technique developed to represent Descartes executable specifications visually by adapting the charts of I. Nassi and B. Shneiderman (1973), is described. Symbols are identified for the data structuring methods and the rationale for selecting these symbols is discussed. The benefits gained in moving a graphical technique up to the front end of the software life cycle are discussed. Sample specifications are included to illustrate the effectiveness of the technique.<<ETX>>

RealSpec: An Executable Specification Language for Modeling Control Systems

Direct support of real-time and control system features in a real-time specification language has a key role in the modeling of such systems. Correct modeling constructs in a specification language simplifies specification construction and enhances specification comprehension. This paper presents enhancements to an executable real-time specification language with constructs to model control systems. Two key control system modeling constructs are added to the language. The details of the constructs are discussed and the concepts are applied to model a gas burner system in the RealSpec language.

A visual syntax-directed editor for the Descartes specification language

The front end of the software life cycle is an important phase in the development of quality software systems. Due to the interactive nature of the requirements specification phase, automated tools assist in capturing user concepts and conveying these concepts to the developers. This paper presents a syntax-directed editor developed for the Descartes software specification language. The editor helps in constructing the specifications by detecting and preventing syntactic and static semantic errors. The editor uses the visual notation of Nassi–Shneiderman charts for the external representation of Descartes specifications. The specifications are edited in their visual form directly within the editor. Use of a syntax-directed editor for the construction of Descartes specifications is expected to reduce specification errors, enhance constructibility, and in turn increase productivity.

RealSpec: An Executable Specification Language for Prototyping Concurrent Systems

RealSpec is a declarative executable language for the prototyping of concurrent and real-time systems based on a dataflow functional model. RealSpec is developed on top of Lucid dataflow programming language by enhancing Lucid with features for real-time systems. This paper provides basic RealSpec language constructs for modeling concurrent processes, multithreading, and resource modeling. The producer consumer example is used to demonstrate the applicability of these language features.

A FRAMEWORK FOR THE EVALUATION OF REAL-TIME SPECIFICATION TECHNIQUES

Real-time and embedded software systems are becoming increasingly prevalent in everyday life. Well-defined and robust methods and methodologies are needed to support development and maintenance of such large and complex systems. Specification of a system is a critical phase of the development life cycle and has a major impact on the quality of a system. Formal specification languages and techniques are needed to be able to comprehensively and correctly define and prototype large and complex systems. The quality of a specification directly depends upon the capability of the language or technique used to express the specification. There is a need to determine language appropriateness for real-time systems. This paper establishes a real-time specification technique evaluation framework based on the features of real-time systems. The features are presented and the paper summarizes the result in terms of major features and their sub-features in a tabular form. This detailed list of features should serve not only to compare the techniques using a common framework, but also to determine the extent of real-time support that these techniques provide for specification. Application of the framework is demonstrated by testing a set of specification techniques for the specification of a real-time embedded cell phone software system.

An MFC based multi-threaded test environment for the validation of an embedded automotive microcontroller

Embedded microcontrollers are used in a multitude of commercial applications such as modems, motor-control systems, air conditioner control systems, automotive engine and antilock braking systems among others. The high processing speed and enhanced peripheral set of these microcontrollers make them suitable for such high-speed event based applications. However, these critical application domains also require that these microcontrollers are highly reliable. The high reliability and low market risks can be ensured by a robust testing process and a proper tools environment for the validation of these microcontrollers both at the component and at the system level. Intel(R)s Chandler Platform Engineering department developed an object oriented multi-threaded test environment for the validation of its 8XC196EA automotive microcontrollers. The goals of this environment was not only to provide a robust testing environment for the 8XC196EA automotive microcontrollers, but to develop an environment which can be easily extended and reused for the validation of several other future embedded microcontrollers. The environment was developed in conjunction with Microsoft(R) Foundation Classes (MFC). The paper describes the design and mechanism of this test environment, its interactions with various hardware/software environmental components, and the pros and cons of using MFC.

Enhancing extensibility of the design rule checker of an EDA tool by object-oriented modeling

Design rule checking systems are an integral part of electronic design automation tools. Rapid advances and continuous change in semiconductor technology requires that these DRC systems also change accordingly. The paper presents the architecture and mechanism of the DRC module of an IC package design tool. Design goals were identified for the module to allow easy addition, removal, and modification of rules and to minimize the effect of changes among others. The object oriented modeling technique facilitates the accomplishment of these goals by supporting concepts such as abstraction, encapsulation, inheritance, and dynamic binding. The paper puts these concepts in perspective within the context of the architecture and mechanism of the DRC module.