| 摘要 |
PURPOSE:To attain communication with high efficiency even with a transmission line of low quality by inserting a cancel control character after the character having a transmission error in a transmission data string and at the same time continuing the data strings at and after the character that has a transmission error thereafter. CONSTITUTION:The transmission signal delivered from a certain transmission terminal Ti (i=1-n) to a bus 20 is sent through an ascending transmission cable 21 and then returned in the opposite direction at a return point 23. The terminal Ti transmits an output data string and at the same time compares a transmission data string with a reception data string successively for every character to check whether or not the signals are returned correctly. Then the terminal Ti does not transmit the next character E if a transmission error of a character D, for example, is detected and adds a cancel control character CAN to continue the data strings following the CAN after said CAN. When a reception terminal Tj receives a data string including the CAN, the terminal Tj disuses the CAN and its preceding characters and decides the rest reception data strings as a regular reception telegram. |
