Modular multiplex/demultiplex apparatus

Modular multiplex/demultiplex apparatus suitable for use in a telephone communication system for processing data transmitted between local and remote telephone subscribers. The multiplex/demultiplex apparatus comprises a plurality of module units which may be interconnected together, for example, in one or more groups, for processing and routing data originating with local subscriber equipment to selected ones of a plurality of trunk group modules and associated modems for transmission to remote subscriber equipment, and for processing and routing data received by the trunk group modules and modems from remote subscriber equipment. Each module unit includes a shift register having a plurality of demultiplex input lines for receiving demultiplexed data thereon and a series input for receiving multiplexed data. Data present on the demultiplex input lines or at the series input is shifted to an output of the shift register. The module unit further includes a plurality of multiplex output lines and associated gates connected to the multiplex output lines and in common to the output of the shift register. One of the multiplex output lines represents a module interconnection line and is connected to the series input of the shift register of an adjacent module unit. Data shifted to the output of the shift register is selectively gated through one of the gates to either the multiplex output line connected to the series input of the shift register of the adjacent module unit or to one of the other multiplex output lines to an associated trunk group module and modem.