| 摘要 |
PURPOSE:To prevent the confusion of a telephone circuit network due to a fault of a computer, etc., by adding transmitting and receiving circuits of a signal to a network controller to transmit and receive the signal in addition to the control executed by an electronic computer, etc. CONSTITUTION:An electronic computer 2 is connected to a telephone circuit 3 via a network controller 1, and this controller 1 is provided with a signal transmitting circuit 12, a signal receiving circuit 13, a communication fault detecting circuit 18 and an outgoing/incoming control circuit 14. These circuits 12, 13, 14 and 18 are connected to a microprocessor 11. In case the communication has no reply between an interface circuit 15 of the controller 1 and the computer 2 or a system breakdown switch 19 of the circuit 18 is set, the processor 11 decides a fault of the computer 2 and has an automatic incoming reply by control of the circuit 14. Then the processor 11 switches a data communication line 20 to the side of the computer 2. Then the circuits 12 and 13 transmit and receive signals in addition to the control of the computer 2. This prevents the confusion of the circuit 3 due to a fault of the computer 2, etc. |
