| 摘要 |
PURPOSE:To improve the system performance of data transmission by providing a special interruption mode to detect a specific slave station and executing data transmission/reception with the slave station and informing the end of data transmission/reception to a terminal device after the end. CONSTITUTION:Interruption codes INTO, INT1,-INTn are set by taking a specified supervisory time T as a time interval in the master station transmission data, a slave station address is scanned sequentially, and a slave station, e.g., slave station 2k, subject to input data change from a terminal device 7 returns an ACK signal only when the address (k) is accessed. Only when the ACK signal is returned within the specified supervisory time T from the slave station 2k, the mode is transited to the normal transmission mode, the data transmission with high reliability is attained, and when it is finished, the changed state of all slave stations 21, 22-2n are scanned at the said interruption mode again. |
