| 摘要 |
PURPOSE:To transmit descending information quickly without generating transmission delay in ascending information by using a poling method for the ascending information and transmitting the descending information by using the idle time of the poling cycle. CONSTITUTION:When descending information other than a poling signal does not exist, information Ri-1 is transmitted from a local office receiving the poling signal Pi-1 sent from a master office, and immediately after receiving the information Ri-1, the master office transmits a signal Pi to the succeeding different local office. The master office receives information Ri from the local office receiving the signal Pi and repeats said operation. If descending information to be transmitted is generated, the information is transmitted as a signal Cj during the idle time of a descending transmission circuit which does not transmit normal poling signals Pi-1, Pi.... At that time, respective pieces of information Ri-1, Ri... from local offices to the master office are transmitted by the ordinary poling method. |
