PURPOSE: To prevent an erroneous processing caused by missing or overlapping supervisory information by adding a serial number for the unit of each kind of information on the transmission side, transmitting the information and deciding the missing and overlapping of the information according to the continuity of the serial numbers on the reception side.
CONSTITUTION: At a transmitting station 1, a serial number adding part 5 adds the serial numbers of information as a part of various information to be loaded on an information field in frame configuration and when the information to be loaded on the information field is composed of plural kinds, the sequential serial number is added for each kind of information. At a receiving station 2, a serial number control part 7 controls the serial numbers while deciding the missing and overlapping of the received information by comparing sizes between the serial number of an expected value and the received serial number for each kind of received information. Thus, since the missing and overlapping of the information can be managed on the reception side, the erroneous processing can be surely prevented.
AKASHI TETSUO
KAWABE KOICHI
MEIDENSHA ELECTRIC MFG CO LTD