Abstract: An electronic apparatus comprising a detecting unit, a communications unit, and a power control circuit. The power control circuit supplies power to a communication circuit unit based upon a result of detection of the detecting unit.

Abstract: Between two nodes, data in the form of two different signals are transmitted bidirectionally, in accordance with IEEE1394 through one optical fiber cable. At the time of data transmission, data of two different signals is converted to data of one type of signal at one node, and transmitted to the optical fiber cable, and at the other node, the data received from the optical fiber cable is converted to the original data of two different signals, and transmitted to a subsequent processing circuit in accordance with IEEE1394. At this time, in a transmission sequence for requesting and granting priority of transmission over the optical fiber cable between both nodes, the priority of transmission is granted alternately to both nodes.

Abstract: In a communication network in which a plurality of equipments each having a function implementing unit having a plurality of functions and a communication control unit having communication function communicating with each other, the communication control unit includes a recording medium and stores on the recording medium in advance a plurality of pieces of function information related to at least one function held by the corresponding function implementing unit, and inquires function information of each of other equipments at the time of communication. Therefore, management of various equipments and function information of various equipments in correspondence with each other becomes unnecessary, load in processing including communication is relieved and functions of respective equipments can be controlled efficiently.