A PROCESS AND SYSTEM FOR ERROR DETECTION IN A COMPUTER-CONTROLLED TELEPHONE EXCHANGE

摘要

A method of supervising a plurality of data processing units in a redundant data processing system for controlling a telephone exchange having redundant digital switching networks, preferably of the TST type (Time-Space-Time), said processing units serving i.a. to set up and delete redundant communication channels through the switching networks. The process is original in that error detecting is provided for by comparing associated telecommunication output data from each switching network, a discrepancy in anyone of said comparisons indicating an error in the set up by the controlling units of the respective communication channel through the switching networks. This obviates micro-synchronization of the units which may consequently comprise more than two units. Thus the invention provides for n+1 redundancies and allows a more efficient error finding since a larger number of units can execute a program in a plurality of separate program phases and the said error indicating signal of the invention is used for initiating exchange of the program phases between the units. In a preferred embodiment the exchange is of the TST type (Time-Space-Time switch) and there is provided a plurality of comparator circuits corresponding to the number of output time switches in each switching network, said comparator circuits being directly connected to the respective output time switches for comparing the time division multiplexed output data from the time switches.