The Chance for Ada to Support Distribution and Real-Time in Embedded Systems

  • Juan López Campos
  • J. Javier Gutiérrez
  • Michael González Harbour
Part of the Lecture Notes in Computer Science book series (LNCS, volume 3063)


This paper presents a modification of GLADE – the current GNAT implementation of the Ada 95 Distributed Systems Annex (DSA) – to support the development of distributed applications with hard real-time requirements. This modified implementation, that we call RT-GLADE (Real-Time GLADE), is specially suitable for embedded applications composed of a small number of heterogeneous processors and communication networks, because it ensures pre-dictable timing behaviour. A real-time model of the implementation allows the application developer to determine and optimize the overall timing behaviour by applying the corresponding schedulability analysis and priority assignment tech-niques. This realtime version of GLADE continues to conform to the DSA, so the entire real-time application can be built within the Ada 95 context. To imple-ment RT-GLADE, we provide a priority-based communication network over standard Ethernet that is used to ensure predictable transmission times.


Real-Time Embedded Systems Distributed Systems Ada 95 Modelling Schedulability 


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Copyright information

© Springer-Verlag Berlin Heidelberg 2004

Authors and Affiliations

  • Juan López Campos
    • 1
  • J. Javier Gutiérrez
    • 1
  • Michael González Harbour
    • 1
  1. 1.Departamento de Electrónica y ComputadoresUniversidad de CantabriaSantanderSPAIN

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