COMMUNICATION CONTROL DEVICE AND CONTROL METHOD

摘要

If the data type of unprocessed data is not changed when the operation of control units (102a, 102b) is changed, table A' of the control unit (102b) corresponding to table A of the control unit (102a) is all cleared, and table B is created in an area different from that of table A'. The data of old type stored in table A is converted to data of new type. The data of new type is stored in table B. When the conversion of the old type to the new type is started, the differential data (data of the old type) written in the control unit (102a) is stored in table A' the data of which is cleared. The stored differential data is converted data of the new type. The data of the new type is written in table B. The related data of table A' is cleared. When differential data disappears by the type change, the system is switched from the operating one to the standby one.