| 摘要 |
PURPOSE:To attain effective retransmission by transmitting a link setting frame in which the list of a disconnected slave station is set when the quality of a line is deteriorated and when a master station retransmits data to a slave station which is set to be the out of communicating object, grasping the state of the slave station and performing retransmission. CONSTITUTION:When the quality of the line is deteriorated in the middle of data transmission and the master station sets the slave station which becomes unreceivable to be out of the communication object and it retransmits data to respective slave stations after first communication terminates, the interface part 102 of a multiple address communication controller 302 informs a disconnection control part 104 of the threshold value of the number of answers with respect to the link set frame which is informed from a computer and which has been disconnect-controlled and a timer value showing transmission intervals, and gives multiple address information to a transmission control pare 103. It informs a disconnection control part 104 of the address of the disconnected slave station when the slave station is disconnected after the termination of transmission. It supervises the answer to it, grasps the reception state of the slave station and retransmits multiple address to the disconnection control part 107. Thus, effective communication is attained while normal transmission control is not affected. |
