STATUS READING SYSTEM FOR DUPLICATED DATA HIGHWAY SYSTEM

摘要

PURPOSE:To shorten the detecting time for the area of fault, by always securing a coincidence between the system displayed by a system control circuit and the system of an end office device that delivered the status. CONSTITUTION:When the system control circuit indicates the 1-system status reading, the central device control circuit 1110 turns the route discriminating data to ''0'' and renews the end office address successively. Thus the end office controllers 1210, 1310, 1510 and 1610 transmit the 1-system side status, and the 1- system status can be read out through the central device excepting the end office 1400. When the system control circuit indicates a reading of the 0-system status, the central device control circuit 1110 turns the route discriminating data to ''1'' and renews the end office address successively. Thus the end office controllers 1211, 1411, 1511 and 1611 transmits the 0-system side status, and the 0-system status can be read out through the central device excepting the end office 1300. In the case of the end office 1300, a nonresponse display of the 1-system side is obtained in the form of a nonresponse.