Abstract: The invention concerns a method for supporting communication between a switching system and a PSTN terminal connected with a network termination unit through an analog subscriber line. Broadband traffic packets as well as a number of synchronous channels are transferred in both directions over a subscriber line between the network termination unit and the subscriber line board of the switching system. At least one ISDN-B channel and one ISDN-D channel is provided based on such synchronous channels. A protocol converter converts between an analog loop signaling applied on the analog subscriber line and digital signaling messages transported over the ISDN-D channel. An analog to digital conversion is performed between the analog subscriber line and the ISDN-B channel.

Abstract: The invention concerns a program-controlled device with reloading possibility for and change-over possibility to a second operating system (GLS1, GLS2, GLS3, GLSx) without program interruption, with a processor and a program memory which the processor can address via address lines, where a switchable change-over switch is provided in the address lines whereby two memory areas (01xx, 10xx) can be exchanged with each other by means of translation.

Abstract: Thyristors utilized as protective elements receive trigger current by way of a respective semiconductor switch having a control electrode thereof coupled to a supply battery. The supply battery thus need only supply the sum of control currents for respective semiconductor switches whereas the current required by the protective thyristors is provided by the interfering source, for example, by a stroke of lightning.

Abstract: A circuit for subscriber line interface circuits in a digital time-division multiplex communication switching center is disclosed. In the case of reception of the same information on the same time slot allocation via a number of subscriber line interface circuits, a transmit time slot as well as a receive time slot is alloted, but access of the transmit driver stages of the subscriber line interface circuits to the bus conductors leading to the switching center is prevented in order to avoid damaging interacting final stages in the transmit driver stages of the subscriber line interface circuits.

Abstract: A digital interface between at least two subscriber line interface circuits and a processing unit is described. The interface is configured in the form of a parallel interface. The level of an input/output register and of a control register is allocated, as needed, to the connections of the processing unit. These connections can be operated selectively as inputs or outputs. They can also be operated in two modes, depending upon which type of subscriber line interface circuit (SLIC) is connected. The connections of the last-mentioned units are partially operable as inputs or outputs and partially operable only as inputs but in the input case, selectively for various types of input signals.

Abstract: A digital interface of an integrated subscriber line interface circuit is provided. The interface serves for the connection of a signal processor unit. Individual connections are used as signal inputs in signal entry operation of the interface, and as signal outputs in signal transmission operation. Other connections are used as signal inputs in both operating mode, but receive different signals in each operating mode. One group of connections includes two registers with respective associated decoders to enable switching from one to the other, so that the number of operating instructions that can be represented by means of binary signal value combinations applied to the connections is doubled.

Abstract: In a subscriber termination module for coupling a plurality of subscriber termination lines of a digital time multiplex telecommunications network, lines coupling a central portion and local portions individually allocated to at least one subscriber termination line are selectably utilized for the transmission of status setting information to the local portions for setting different operating conditions and for serial transmission, that is, successive transmission of information to be supplied to the individual local portions as well as for simultaneous information transmission from the local portions to the central portion, that is, parallel information transmission.

Abstract: The invention relates to a circuit arrangement for the indication of loop closure during the ringing condition for a subscriber circuit which is connected to the exchange of a digital time multiplex telephone system by way of a subscriber termination circuit comprising a subscriber line interface circuit which, in part, provides the ringing supply and signalling, and a signal processing unit which, in part, provides for analog to digital conversion and digital to analog conversion as well as for filtering.The circuit arrangement includes a changeover switch, by way of which, a signal representative of the subscriber termination line current is applied to the signal processing unit during the ringing condition, in place of the speech signal present during the speech condition.