Service robots are complex, heterogeneous, software intensive systems built from components. Recent robotics research trends mainly address isolated capabilities on functional level. Non-functional properties, such as responsiveness or deterministic behavior, are addressed only in isolation (if at all). We argue that handling such non-functional properties on system level is a crucial next step. We claim that precise control over application-specific, dynamic execution and interaction behavior of functional components -- i.e. clear computation and communication semantics on model level without hidden code-defined parts -- is a key ingredient thereto. In this paper, we propose modeling concepts for these semantics, and present a meta-model which (i) enables component developers to implement component functionalities without presuming application-specific, system-level attributes, and (ii) enables system integrators to reason about causal dependencies between components as well as system-level data-flow characteristics. This allows to control data-propagation semantics and system properties such as end-to-end latencies during system integration without breaking component encapsulation.