Two transfer modes of a band-guaranteed cycle and an event-driven asynchronous cycle are defined in a multimedia bus. In the band-guaranteed cycle, stream data is transferred between nodes in real time using a reserved band for each cycle time. Both a single-edge access and a double-edge access are provided for the stream data transfer in the band-guaranteed cycle, and it is possible to select one of the single-edge access and double-edge access for each data transfer between nodes. The transfer band of stream data on the bus can thus be expanded and the transfer efficiency of AV stream can be improved.