| 摘要 |
PURPOSE:To shorten control time from a blocking state to the incorporation of an in-use system, by providing a communication controller with a transmitting and receiving means for an indication signal for blocking release and a confirmation signal for the blocking release through a circuit in a blocking state. CONSTITUTION:Under the control of a central controller 1a, data from the storage device 1b of a communication controller 1 is passed through a data channel controller 1b and a data transfer controller 1e and then transferred to a communication controller 2 from a modulator and demodulator 1f through a data circuit l1. In this case, when, for example, a fault in a parity check is detected by a transfer controller 2e, a signal for blocking the circuit l1 is transferred between the communication controllers 2 and 1 through a normal circuit lm. Once the circuit l1 recovers from the fault, an indication signal for blocking release is sent through the modulator and demodulator 1f under the control of the controller 1a, and the controller 2 when receiving it clear blocking display in a state storage device to send a confirmation signal for the blocking release out of the modulator and demodulator 2f. Once receiving it, the controller 1 performs blocking releasing operation similarly. |
