The standard can go up to 131 bits and the extended frame can go up to 156 bits.
The high performance and reliability of CAN has been recognized and is widely used in industrial automation, ships, medical equipment, industrial equipment, and so on. Fieldbus is one of the hotspots of technological development in the field of automation today, and is known as the computer LAN in the field of automation. Its emergence provides strong technical support for distributed control systems to realize real-time, reliable data communication between nodes.
Expanded Information:
CAN bus through the CAN transceiver interface chip The two outputs of the 82C250, CANH and CANL, are connected to the physical bus, while the state of the CANH terminal can only be high or suspended, and the CANL terminal can only be low or suspended. This ensures that there will be no phenomenon in the RS-485 network, that is, when there is an error in the system, there are multiple nodes sending data to the bus at the same time, resulting in the bus presenting a short-circuit, thus damaging the phenomenon of some nodes.
And CAN nodes in the case of serious errors with automatic shutdown of the output function, in order to make the bus on the other nodes of the operation is not affected, so as to ensure that there will not be like in the network, due to individual node problems, so that the bus is in a "deadlock" state. Moreover, CAN has a perfect communication protocol can be realized by the CAN controller chip and its interface chip, which greatly reduces the difficulty of system development, shorten the development cycle, these are only electrical protocols RS-485 can not be compared.