Abstract: A terminal serving a group of subscriber lines, some of which are invariably paired with remote stations through so-called "hot-line" connections, has a line concentrator/distributor from which a lesser number of line links extend to an automatic exchange at a nodal point of a data and/or voice telecommunication system. The line concentrator/distributor is controlled by a marker connected via a separate signaling channel with a line-control unit at the nodal point, that unit including a classifier which stores information fully identifying each associated subscriber line in terms of call number and class of service while also correlating the address of each line link on the terminal side with that on the address side.

Abstract: A multiplicity of peripheral units are consecutively scanned, in respective phases of a recurrent operating cycle, by a central unit including a processor for incoming and outgoing data. The processor is connected to a programmer emitting a series of binary instructions during each phase, the instructions being stored in a read-only memory from which they are read out during respective subphases of each phase under the control of an address counter, the last instruction of a series carrying a characteristic bit which advances a phase counter and causes a switch of the central unit to a different peripheral unit.