Platform-based design of embedded systems on a chip consists of the parallel functionalapplication specification, configuration of the hardware platform (i.e. connection of processing,memory and physical communication channels) and mapping of the application descriptionon the processing, memory and communication resources of the hardware platform. Themain contribution of this work is the seamless object-oriented modeling and automaticrefinement of communication. In the application model, communication is specified by methodcalls on communication objects, independent from a physical communication channel. Bymeans of mapping rules, these application model method calls are automatically transformed(synthesized) and implemented on the processing, memory and communication resources of thehardware platform. This approach enables the exploration and assessment of the impact ofdifferent platform configurations and mapping rules on functional and extra-functional properties.