Abstract: A line trunk group is connected by way of a compensating memory to an input and, in fact, to those of the time slot multiples of the PCM switching network. Uniform time slots of the pulse frame boundaries within the switching network are provided. However, in the last switching stage and, in fact, in time slot multiples, displacement of a pulse frame boundaries in the lines leading back to the trunk line groups is provided. In this manner, line trunk groups acquire the frame clock rate. This influences, in respect of time slots, the transmission of sub-items of information from the line trunk groups to the switching network with regard to pulse frames of these sub-items of information, i.e. the relevant time slot of the pulse frame boundaries.

Abstract: Due to a control engineering context, write and read pulse frames of time-slot multiplexers of different switching matrix stages in a multi-stage, time-division multiplex switching matrix network exhibit coinciding pulse frame boundaries. In deviation therefrom, pulse frame boundaries of the pulse frames on switching network internal time-division multiplex lines are offset due to delays that are caused by serial-to-parallel and parallel-to-serial conversions of a partial information upon their intermediate storage in the time-slot multiplexer. Of two complete memories per time-slot multiplexer, one part of the one memory and another part of the other memory are inscribed during the pulse frame of an incoming time-division multiplex line.

Abstract: A switching arrangement for pulse code modulation (PCM) time division multiplex telecommunication switching system is described. The frame storages for incoming and outgoing directions of transmission as well as their address memories, and the crosspoint address memory form a memory unit. The frame storages are read-in in cyclic sequence and read out selectively and it is possible to transfer information from anyone of the frame storages to either the same PCM trunk or to the space division switching network. Thus, there is a possibility both for return switching to the same PCM trunk and for switching through other switching units in a time-space-space-time format.