Times is a modelling and schedulability analysis tool for embedded real-time systems, developed at Uppsala University in 2001. It is appropriate for systems that can be described as a set of preemptive or non-preemptive tasks which are triggered periodically or sporadically by time or external events. It provides a graphical interface for editing and simulation, and an engine for schedulability analysis. The main features of Times are:
A graphical editor for timed automata extended with tasks [1], which allows the user to model a system and the abstract behaviour of its environment In addition the user may specify a set of preemptive or non-preemtive tasks with parameters such as (relative) deadline, execution time, priority, etc.
A simulator, in which the user can validate the dynamic behaviour of the system and see how the tasks execute according to the task parameters and a given scheduling policy. The simulator shows a graphical representation of the generated trace showing the time points when the tasks are released, invoked, suspended, resumed, and completed.
A verifier for schedulability analysis, which is used to check if all reachable states of the complete system are schedulable that is, all task instances meet their deadlines. A symbolic algorithm has been developed based on the DBM techniques and implemented based on the verifier of the Uppaal tool [2].
A code generator for automatic synthesis of C-code on LegoOS platform from the model. If the automata model is schedulable according to the schedulability analyser the execution of the generated code will meet all the timing constraints specified in the model and the tasks.