| 摘要 |
PROBLEM TO BE SOLVED: To perform communication between a security control device and a maintenance apparatus, while taking into consideration the security mode.SOLUTION: The security control device includes a communication specification table, in which a plurality of communication specifications having different transfer speeds are stored. A PC for maintenance includes a communication specification table in which communication specifications of the PC itself are stored and a communication specification designation table 311 for designating one communication specification from the communication specification table of the security control device. When communication between the PC and the control device is started, the present security mode and the load state of the control device are transmitted from the control device to the PC. The PC selects a communication specification from the communication specification designation table, based on the combination of the security mode and the load state and transmits the information of the selected communication specification to the control device. The control device selects a communication specification from the communication specification table in accordance with the received information and determines the communication specification of communication between the control device and the PC, based on the selected communication specification. The PC also determines the communication specification of communication between the PC and the control device, on the basis of the communication specification selected from the communication specification designation table in accordance with the combination of the security mode and the load state. |
