| 摘要 |
PURPOSE:To obtain smoothly the right of transmission by a request acceptance command from a station which holds the right of transmission currently, by outputting a transmission right request command from a station which has a request to send. CONSTITUTION:In a network, a station A has a reader R and a printer P and a station B has only a printer P. A station C, on the other hand, has only a reader R. Each station is provided with a communication module. A communication module A' has a function for supply a command to other stations according to a request to send from a user and a communication module B' has only a function for operation command in response to input command information (command information). Then, a response command from a prefetch priority type soft master is waited for and once information on the transfer of the right of transmission is received, the right of transmission is obtained firstly to serve as a new soft master. The soft master station outputs a command equipped with a confirming function for connection states of stations constituting the communication system and a reporting function for the confirmed connection states to a communication circuit at specific intervals of time. |
