| 摘要 |
PURPOSE:To realize a loop transmission in an economical way, by making full use of an optical transmission line. CONSTITUTION:Transmission controlling stations 12 (12-1-12-n) are connected to a loop transmission line 11 of an optical cable to stoe many data communication devices 13 (13-1-13-m). Thus mutual communication is carried out between a device 13 belonging to an optional station 12 and another device 13 of another station 12. In this case, the station 12 divides the telegrams sent from the device 13 to the telegram unit or subblocks and composes the information frames. The information fame including the data addressed to the device 13 of another station 12 is fed to the line 11 based on the prescribed order of transmission. Then the other station 12 receives the information frame and then distributes the data addresses to the own device 13 to the corresponding device 13 when the data is found out. When the transmission is over for the information frame of a station 12, the right of transmission is shifted to the subsequent station 12. |
