The new data exchange facilities with CAN-FD

The modern vehicles demand more and more data exchange to coordinate, control and monitor functions of on board system. The variety of networks applied in these systems is featured mainly by the bandwidth and time determinism. The development electronic information and network sciences find its reflection in the new and new automotive implementations. The last significant step towards the increase the throughout put of the on board network channels are works on CAN-FD. CAN is now the most common network present on board. It helps to manage the maintenance with the numerous subassemblies of the modern car. Next to the many features making CAN so useful and popular, there is a bandwidth limitation, which slows down further implementation of it. The new CAN-FD specification adds new properties that extend the possibilities of CAN as automotive network protocol. These are: different speed transmission in the arbitration phase and in the data phase during the message transmission as well as the extending the maximum size of data filed of the frame from 8 (CAN) to 64 (CAN-FD). In the paper there have been presented the limitations of existing CAN protocol usage, the explanation of the basics of the arbitration mechanisms and the response of the scientist and engineers to cope with it, as well as the formal result outlined in the CAN-FD specification.