Abstract—The SPEEDS project is aimed at making rich components models (RCM) into a mature framework in all phases of the design of complex distributed embedded systems. The RCM model is required to be expressive enough to cover the entire development process from requirements to code through design, and also capture both functional and non-functional aspects. In this paper we propose a language-based framework for real-time component interfaces in SPEEDS that is suitable at the ECU layer when a target processor has been identified, and WCET analysis done. We assume a discrete time model.