Patent ID: 7075898

Claim:
A method for an exchange of data in messages between at least two users connected by a bus system, each one of the at least two users including at least one of a predefinable timing mark and an ascertainable timing mark, comprising the steps of: causing the at least two users to transmit via the bus system messages including the data; causing a first one of the at least two users, in a function as timer, to control the messages as a function of time such that the first one of the at least two users repeatedly transmits a first reference message including a first time information regarding a time base of the first one of the at least two users, via the bus system at a specifiable time interval; if the at least one of the predefinable timing mark and the ascertainable timing mark of a second one of the at least two users is reached without the first reference message of the first one of the at least two users reaching the second one of the at least two users, causing the second one of the at least two users to take over the function of timer by transmitting a second reference message with a second time information via the bus system; subdividing the specifiable time interval into timing windows of a specifiable length; transmitting the messages including the data in the timing windows; and combining one of the first reference message and the second reference message and subsequent ones of the timing windows up to a next reference message to form a first cycle of at least one of the specifiable length and a specifiable structure, wherein: the specifiable structure corresponds to the specifiable length, number and time position of the timing windows in the specifiable time interval following the one of the first reference message and the second reference message.