| 摘要 |
PURPOSE:To uniform the priority of transmission control shared by each slave station by activating a timer incorporated in each slave station through simultaneous polling, and confirming that no signal exists on a transmission line after time-up of the timer, and transmitting data. CONSTITUTION:Each slave station 2 activates the timer 9 to simultaneous polling from a master station so as to check the presence of a transmission data of the own station after time-up of the timer. When no transmission data exists, after the absence of signal is confirmed on a transmission line 3 by a transmission line signal detector 5, the data is transmitted. When the presence of the signal on the transmission line 3 is discriminated by the transmission line signal detector 5, no data is transmitted and the next polling is awaited. |
