| 摘要 |
PURPOSE:To prevent the lowering of the data transfer capability of the system, by using an optional idle channel on a trunk circuit to transmit and receive control information such as a line folding instruction. CONSTITUTION:When the transmission of control information such as a line folding instruction and a backup instruction from a multiplex concentrator and alloter device 4 to a multiplex concentrator and alloter device 9 in the center side is required, a trunk circuit control part 44 of the concentrator and alloter device 4 scans parameter set areas to search an idle channel. When an idle channel is found, a specific address is set to the parameter set area of this channel, and this channel is used to transmit control information with partitions of every four bytes. Meanwhile, the trunk circuit control part 44 of the concentrator and alloter device 9 in the center side receives this transmission sgnal; and when it is discriminated that an identification code of address information is set in the first byte and following three bytes are equal to one another and indicate an address for control information, the trunk circuit control part 44 judges that succeeding data on this channel is control information, and the trunk circuit control part 44 transfer address contents to a specific control part. |
