Differentiation of electrical parameters of CAN protocol signals in vehicles

The article presents the concept of operation of a bus based on the Controller Area Network protocol, taking into account the method of controlling access to the bus. Special emphasis is placed on the parameters of the physical layer (voltage levels, bus speed). The actual communication signal waveforms presented in the article, originating from vehicle CAN buses, along with the calculated timing parameters, will allow one to understand why it is so difficult to communicate with vehicle controllers using a single diagnostic tester.The efforts of mechanical engineers to increase the functionality, reliability, and comfort of using means of transport are accompanied by work in the field of broadly understood electrical engineering, electronics, and computer science. An additional influence on the final shape of the product is exerted by users of means of transport and even organizations that, at first glance, are not directly related to transport, e.g., the EPA (Environmental
Protection Agency).
The mentioned “sources of pressure” have led to the use of data exchange networks in vehicles. (…)

Differentiation of electrical parameters of CAN protocol signals in vehicles – PDF file for download