apparatus for the preparation of a collective communication in pulse modulation codees central line

摘要

1338820 Automatic exchange equipment SIEMENS AG 21 Sept 1971 [30 Sept 1970] 43906/71 Heading H4K A PCM, TDM exchange provides a collective connection whereby a first subscriber can be connected with a plurality of second subscribers where these second subscribers cannot communicate with each other. In the exchange shown the time channels on incoming highways EML1-N are connected with the time channels on outgoing highways SML1-N through pairs of intermediate lines with complementary delay stores Z0, Z6; Z3, Z3SP1/SP and the actual connection is made by switches controlled by rotary address stores UI-UN operating through decoders DEI-N, DSI-N. A special pair of intermediate lines-SV1, SV2 is provided for the collective connection. Information emanating from the first subscriber is stored in the register ZZ which acts as a rotary word store by the action of gates SG and OG so that the stored information can be entered into each collective subscriber's time slot on the outgoing highways. The store is stopped and refilled from the incoming highway for each time frame by applying a signal S to gate SG. For the second subscribers the information appearing in their time slots on the incoming highway is passed through a code converter to change it into a 12 bit code and is serially stored in register R. The bits are passed in parallel into the adder where they are recirculated through the register RR so that as each word arrives from each of the second subscribers it is added to the word(s) already present to make up a total word. At the correct instant the total word is passed to code converter LN where its original 8 bit form is restored and it is transmitted to the first subscriber in the correct time slot on the outgoing highway.