Statecharts for Unified Model-Based Design – As simple as possible, as rich as needed

International audiencesoftware projects using Simulink or Scade use in fact a subset of Simulink or Scade. The ‘alignment’ of these two subsets gives rise to a new concept, the ‘Unified MBD’, whose data-flow part keeps the expressiveness of both languages and has been introduced in a former paper. Here we present the control-flow part, which is much more restrictive, because the automata paradigms of Scade and Simulink differ fundamentally. But in fact, at least in our context, this loss of expressiveness is not a weakness, because our current design modelling practice is consistent with these restrictions, and because it opens the road for simple but faithful specification modelling practice