DATA CHANGE SYSTEM FOR COMMUNICATION CONTROLLER

PURPOSE:To prevent the interruption of a communication process at change of data by adding a table to a communication processor to control the change history of the communication control data on a communication controller. CONSTITUTION:When an access is given to a communication processor 1 from a data terminal 51 via a communication controller 31, for example, the processor 1 refers to a history control table 10 to read the change data on the communication control data out of the communication controller control data 6 as long as the communication control data on the controller 31 is not latest and sends the read-out data to the controller 31 to change the communication control data 81. When an access is given to a data terminal 52 from the processor 1 via a communication controller 32, for example, the processor 1 refers to the table 10 to transmit the change data on the communication control data if the communication control data on the controller 32 is not latest and performs the communication with the terminal 52 via the controller 32 and a communication network 4 after the change of the communication control data 82. Thus it is possible to prevent the interruption of a communication process at change of data.