The invention relates to a periodic communication method between at least one first system (2) and at least one second system (3) by means of a full-duplex synchronous serial link (4), wherein, during a communication period, data are exchanged between the first system (2) and the second system (3), including: at least one message from the first system (2) to the second system (3), at least one message from the second system (3) to the first system (2) and a clock signal, the clock signal being routed by the link (4) over a time interval, the amplitude of which is less than the communication period, the message from the first system (2) to the second system (3) and the message from the second system (3) to the first system (2) both being routed by the link (4) over said time interval.
