| 摘要 |
PURPOSE:To obtain a control method for the occupying right of a loop-shaped data highwat that transfers the right of occupying a circuit in sequence and has the high efficiency of utilization of the circuit, by permitting respective stations in the circuit to exercise at a time control over the right of occupying the circuit once the circuit is free. CONSTITUTION:Stations A having station numbers 1-(n) are connected in a loop by shared transmission line B. When transmission line B has a vacancy, each station A sends the circuit occupying command, including code PADR showing its station number and its priority, to the circuit. Then, PADR is displayed by the difference between the station number of a station, which occupied the circuit up to that point, and its station number. Each station compares PADR of the command sent from the said station at the upstream side to its own PADR and, when its own PADR is less than that of the other station, obtains the right of occupying the circuit. Other stations set as PADR the difference between their own station numbers and the station number of the station having just obtained the right of occupying the circuit and wait for the next circuit vacancy. |
