SYSTEM FOR DETECTING FAULT IN DATA WAY SYSTEM

PURPOSE:To detect a fault quickly by making each station independently monitor a circuit between the self-station and an adjacent station or a station next to the adjacent station. CONSTITUTION:A station ST0 transmits the 1st test signal to a station ST1 through a line L0 and the station ST1 responds to the signal. Subsequently, the station ST0 transmits the 2nd test signal to the station ST2 and the station ST2 responds to the signal. At that time, the station ST1 performs repeating operation. If a response from the station ST2 does not arrive within a fixed period, the station ST0 transmits the 3rd test signal to the station ST1. The station ST1 transmits the contents of a fault to the station ST0.