ELECTRONIC CONTROL-SYSTEM FOR CROSSBAR SWITCHES

This article describes a solution to the problem of introducing the new numbering plan for the French network in crossbar exchanges controlled by electromechanical units. The solution proposed is designed by LMT. It consists in replacing the inflexible electromechanical control circuits in existing exchanges by new electronic microprocessor-controlled interface units, which are connected to a pair of central computers. These are the same computers used in all LMT electronic, stored-program-controlled exchanges. This solution has the further advantage of making it possible to introduce new subscribers' facilities and to improve administration features, so as to upgrade crossbar exchanges to a level approaching that of the new electronic exchanges. It is considered that this is the best way to transform the present French crossbar network into the new electronic switching network.