The long-term goal of this project is to develop adequate languages for the specification, modelling, and programming of hard real-time systems, in particular in embedded systems. This research is motivated by the need for efficient and safe design of these systems, and we believe that currently used languages, like C, do not provide adequate support for all aspects of the design process.
Real-time and embedded systems are often reactive in nature, meaning that execution is driven by external events to which the system should respond with appropriate actions. Such events can be simple, but many systems are supposed to react to sophisticated situations involving a number of simple events occurring in accordance with some pattern. A systematic approach to handle this type of systems is to separate the mechanism of event pattern detection from the definition of appropriate responses. The event detection mechanism can for example be based on an event algebra, i.e., expressions that correspond to the event patterns of interest are built from simple events and operators from the algebra.
We have developed a novel event algebra with two important characteristics: It complies with intuitive algebraic laws and the detection can be correctly performed with limited resources in terms of memory and time. The future work includes formulating schedulability analyses and scheduling algorithms for tasks triggered by event algebra expressions, in particular for the case when these tasks exist together with time triggered tasks with hard deadlines.
Event-Pattern Triggered Real-Time Tasks (Oct 2008) Jan Carlson, Jukka Mäki-Turja, Mikael Sjödin 16th International Conference on Real-Time and Network Systems (RTNS)
An event algebra extension of the triggering mechanism in a component model for embedded systems (Apr 2005) Jan Carlson, Mikael Åkerholm Formal Foundations of Embedded Software and Component-Based Software Architectures (FESCA)