This invention is concerned with an interface for a computer system. This interface is characterized in such a way that it includes an assembly of elements (C2, C2') capable of performing an AND function, controlling modules (K1, K1') for monitoring the function of these elements (C2, C2
The state of an all-or-none modulated useful signal subjected to a perturbed environment is determined, on reception, through the use of non-modulated reference signals subjected to the same environment. The reference signals have respective frequencies neighboring that of the useful
