Time - multiplex - communication system with a common local transmission path and local time slot for switching internal calls.

摘要

PURPOSE:To attain the intra-office exchange by receiving a control signal sent to a slave station so as to activate a changeover means in an interface circuit when terminal equipment making communication via a time division multiplex line are terminals belonging to one and same slave station. CONSTITUTION:When, for example, an exchange 50 detects it that terminal equipments making communication via a terminal division line, e.g., lines 30-1, 302 belong to one and same slave station 201, the exchange 50 sends a control signal to the slave station 201 via a base station 100. The slave station 201 uses control means 7, 8 to extract the control signal from a reception data line 81 causing a changeover means 11 in an interface circuit to apply switching. As a result, since both the transmission system and the reception system in both the interface circuits are connected by the 1st and 2nd data lines, the said terminal equipments attain mutual communication not through the base station 100 but through the 1st and 2nd data lines. In this case, a time slot decided based on a frame signal sent to a frame signal line 84 is assigned to a communication channel between both the terminal equipments.