| 摘要 |
PURPOSE:To play the bracketing function at the occurrence of failure, by enabling the connection test with the DDX interface without the DDX (digital line conventional exchange) network with the communication control unit itself, in the communication control unit incorporating data circuit terminal simulator. CONSTITUTION:The data circuit terminal DCE simulator control section 13 and the line mode memory register 14 are provided in the unit 2. This simulator simulates the function of conventional exchange network for digital lines DDX by NIPPON DENSHIN DENWA KOSHA (Nippon Telegraph and Telephone Corporation). Accordingly, direct operating test can be made by the loop connection of the simulator and the unit main control section through the line connection terminal without using DDX network. Accordingly, the bracketing function of network failure or failure in the unit 2 can be played at the production of a failure. |
