TELECOMMUNICATION SYSTEM FOR TRANSMITTING DATA INFORMATION BY MEANS OF A DIGITAL EXCHANGE

A telecommunication system for utilizing a telecommunication exchange intended for transmitting digital information between a plurality of extensions for transmitting between data terminals data information having different rates. Word forming means (18, 19) at the extensions subdivide the data flow into words of given length, buffer means (24) store a plurality of words before sending these out over the line, which is done with the bit rate given by the transmission system for digital information, and frame forming means (30) form frame heading words which precede the frames and have a plurality of subsequent data words. The frame heading word includes a frame locking word for synchronization on the receive side and a frame length word for indicating the number of the subsequent data words. Counting means (29) count the number of words in the buffer means and a control logic (34) controls transmission of data words and the frame heading word such that as soon as the heading word with information on the number of data words has been transmitted there follows transmission of the data words from the buffer means, while the frame heading word by itself is transmitted continuously if the buffer means is empty. On receiving the data signals, a comparison takes place between the incoming binary flow and the frame locking word in a frame locking means (35, 36, 37) for determining the beginning of the frames, the data words are separated from the frame heading word with the aid of filter means (39, 40, 41) and the received data words are stored in buffer means (56) for subsequent output in series form to the data terminal. Un système de télécommunications est utilisé par un central de télécommunications de transmission d'informations numériques entre une pluralité de postes internes pour transmettre entre des terminaux de données des données ayant des vitesses de transmission diverses. Des moyens de formation de mots (18, 19) aux postes internes subdivisent le courant de données en mots d'une longueur déterminée, un tampon (24) mémorise une pluralité de mots avant de les retransmettre par la ligne, la vitesse de transmission des bits étant déterminée par le système de transmission d'information numérique, et des moyens de formation de trame (30) forment des mots d'en-tête de trame qui précèdent les trames et possèdent une pluralité de mots ultérieurs de données. Le mot d'en-tête de trame comprend un mot de maintien de trame pour la synchronisation du côté récepteu