| 摘要 |
PURPOSE:To eliminate the need for the synchronization of the clock of each controller installed decentralizingly and the clock of a database equipment by informing current time information of the clock possessed by the controller to the database equipment and collecting the information with time pattern information possessed by the database equipment. CONSTITUTION:When a current time of a controller 11a is collated with time pattern information in a database equipment 14, the controller 11a reads its own clock 12a to obtain current time information. The controller 11a informs the current time information read with a collation request to the database equipment 14 via a communication line 13a. Then the database equipment 14 uses the current time information informed from the controller 11a and collates it with time pattern information 16 of the database equipment 14. Moreover, the result of collation is informed to the controller 11a via the communication line 13a. Thus, it is not required to completely synchronize the clock of the controllers installed decentralizingly with the clock of the database equipment. |
