Pseudorandom, iterative method and apparatus for automatically creating addresses

摘要

A pseudorandom, iterative method and apparatus for automatically creating an address for each remote unit of a data communication network comprising a plurality of remote units, such as the seat electronic units (17) of a passenger aircraft, and a central unit, such as a central transmitter/receiver unit (13). The formats of the message frames that control the flow of data between the central unit and the plurality of remote units includes a synchronization word, a command word, and a series of data word segments. The number of data word segments is equal to or greater than the number of remote units. The pseudorandom, iterative method and apparatus assigns addresses such that one and only one remote unit is associated with a data word segment position. First, the central unit transmits an ADDRESS ASSIGN PHASE 1 command to each remote unit. In response, each remote unit randomly selects a data word segment position and replies to the central unit in the selected position. Next, the central unit transmits an ADDRESS ASSIGN PHASE 2 command. All of the remote units that replied in the first data word segment position that contained a reply respond to the ADDRESS ASSIGN PHASE 2 command. All other remote units are locked out. The responding remote units randomly select another data word segment position and respond to the central unit in the selected position. The central unit retransmits an ADDRESS ASSIGN PHASE 2 command. All of the remote units that responded, in the first data word segment position that contained a response, reply to the ADDRESS ASSIGN PHASE 2 retransmission. All of the remote units that responded in other positions are locked out. The transmission of ADDRESS ASSIGN PHASE 2 commands is repeated for N cycles. Alternatively, the process can be repeated until the remote unit response is found to be error-free, which indicates that the response was produced by a single remote unit. In either case, after completion of the ADDRESS ASSIGN PHASE 2 command transmissions, the central unit transmits an ADDRESS ASSIGN PHASE 3 command, which instructs the single responding remote unit to assign itself a unique address and, then, lock itself out of the iterative process. Thereafter, the entire process is repeated until no further responses are received to an ADDRESS ASSIGN PHASE 1 command.