Method of monitoring a network of peripheral elements handled by an electronic control unit

A method of monitoring a network of n groups of m peripheral elements, m being an integer greater than 1 and n an integer greater than 2, said elements being handled by an electric control unit, said network being of the type in which the state of each element may be expressed in the form of a binary digit collected on each of m separate channels, wherein said method comprises:

• transmitting along n two-wire channels test pulses recurring in a recurrence interval, corresponding test pulses on the n two-wire channels being staggered as a function of time relative to one another by an interval equal at most to the nth part of the recurrence interval of said test pulses, each two-wire channel comprising means for decoupling d.c. potentials;
• translating the state of an element j (j = integer variable from 1 to m) of any one of the n groups of m elements in the form of a loop state or non-loop state of a two-wire line connecting the network of n groups of m elements to the control unit, each "loop" state being synchronous with a test pulse;
• and
• using the loop states for stopping the transmission of pulses through a receiver (R.sub.i), the non-loop states releasing the same transmission.