Method for synchronising bi-directional data transmission

The Invention relates to a method for synchronizing a bidirectional transmission of Data between a transmitter and a receiver based on the transmission of frames (10) of a predetermined bit length, wherein each frame (10) a predetermined first bit length (20) the transmission of data from the transmitter to the receiver and a predefined second bit length (30) provided the transmission of data from the receiver to the transmitter , wherein parallel to and independent of the transmission the data between the transmitter and the receiver from the transmitter, a trigger pulse (40) to the receiver is sent, which triggers a data recording at the receiver, wherein the frame (10) has a time slot (50), in which neither from the transmitter to the receiver nor by the receiver transmitted to the sender data be, and wherein the trigger pulse (40) in this time slot (50) transmitted from the transmitter to the receiver becomes.