ABSTRACT
Controller area network (CAN) is the leading serial bus for embedded control systems. The main use of CAN has been in the automotive industry. CAN is adopted as invehicle network for engine management, comfort electronics as well as for some infotainment functions. The CAN protocol architecture is structured according to the well-known layered approach foreseen by the International Organization for Standardization (ISO) Open systems interconnection model. The features of the physical layer of CAN that are valid for any system, such as those related to the physical signaling, are described in the ISO 11898-1 document. CAN networks are based on a shared bus topology. CAN relies on the nonreturn to zero bit encoding, which features very high efficiency in that the synchronization information is not encoded separately from data. Bit synchronization in each node is achieved by means of a digital phase-locked loop, which extracts the timing information directly from the bit stream received from the bus.
