Section: New Results

Polychronous controller synthesis from MARTE CCSL timing specifications

Participants : Huafeng Yu, Loïc Besnard, Thierry Gautier, Jean-Pierre Talpin, Paul Le Guernic.

CCSL (Clock Constraint Specification Language) [29] is defined in an annex of the UML MARTE profile [53] . We are interested in the analysis, synthesis, code generation and simulation of polychronous systems specified in CCSL. Timed systems subject to clock expressions or relations can be modeled, specified, analyzed, and simulated within software environments such as SCADE [40] , TimeSquare [44] and Polychrony. The motivation of our work, to address the simulation and code generation of polychronous systems, is to take advantage of the formal framework of Polychrony in the context of a high-level specification formalism, MARTE CCSL [62] . Yet, our work considers a novel approach with regard to previous approaches: to generate executable specifications by considering discrete controller synthesis (DCS) [56] , [51] , [52] .

Based on our previous work on clock hierarchization [61] and the general clock synthesis approach [62] , our current work concentrates on the study of interface-oriented clock synthesis in the context of distributed components. In this work, CCSL clock constraints are specified on the clocked signals that pass through the interface, and the controller to synthesize is used to ensure the constraints. Interface-level synthesis helps to reduce the synthesis complexity since communication concerns and internal component behavior are isolated from the synthesis. The controllability analysis of signals and clock relations are studied with regard to endochronous, polychronous, and reactive components. This analysis leads to the separation of controllable and uncontrollable signals in the synthesis. Observers of CCSL clock constraints have been proposed in order to specify control objectives. In addition, properties of local components and the global system, such as determinism and deadlock, are also initially studied.