Interface circuit for connecting a digital equipment to a time multiplex link

DETAILED DESCRIPTION The present invention thus provides an interface circuit for connecting a digital equipment, at least partially under its own control, for transmitting and receiving digital data to a two-way time multiplex link suitable for transmitting, in byte form, digital data or speech signals converted into a suitable binary form by specialized interface circuits connected in parallel to the time muItiplex link, under the control of a clock module governing byte transmission and receptio by means of clock signals and synchronization signals which are associated with the different time slots available during each frame of the time multiplex link.
According to a characteristic of the invention, said connection interface circuit being provided with a bit transmission terminal and a bit reception terminal enabling it to be connected to the corresponding wires of the time multiplex link in parallel with other interface circuits of equipments for transmitting and receiving digital data or speech signals, includes a synchronization arrangement comprising firstly a local clock generator suitable for receiving from the clook module both a common clock signal and a link bit rate controlling clock signal whose frequency is equal to the frequency of the common clock signal or to a submultiple thereof, and secondly two time slot selection units, one for transmission and the other for reception suitable for receiving the corresponding synchronization signals, in such a manner as to obtain a connection between the connection interface circuit and the time multiplex link which is identical to the connection provided for the interface circuits for converting speech signals, and for automatically adapting to the bit rate capacity provided by the selected time multiplex link.