| 摘要 |
PURPOSE:To avoid such inconvenience in that the MODEMs of both terminals are simultaneously put under the receiving or transmitting state, by giving priority to one of the two terminals for the right of transmission. CONSTITUTION:Each terminal is set as a master (with priority) and a slave (with no priority) in accordance with the priority setting procedure. Then a certain terminal has a request for transmission. In such case, the corresponding terminal checks the presence or absence of the carrier signal at the remote side to discriminate whether the remote side is set in the transmitting or receiving state. In case when the remote side is not in the receiving state with the corresponding terminal is at the master side, this terminal obtains immediately the right for the transmission. Then the carrier signal 15 is transmitted for a certain period of time so that the carrier signal of the master side san be detected at the slave side without fail although the request for transmission is given simultaneously from plural slave sides. Thereafter, the information 16 is transmitted. The slave side is changed to the receiving state after the transmission of the carrier signal 17 and receives the information from the master side. |
