A clock signal constituted by pulses with given frequency of repetition and a data signal is able to assume two logic levels are transmitted simultaneously on a two-wire line in the form of a bipolar differential pulse signal with frequency of repetition of the pulses equal to the frequency of repetition of the pulses of the clock signal and in which the sign of the pulses of the pulse signal applied to said two-wire line varies according to the logic level of the data signal.