What are the commonly used can protocols?

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CAN bus, also known as controller local area network, was developed by Bosch Company in Germany to serve the upgrade of automotive electronic products. The operation of CAN bus should follow the special CAN protocol, just as we should follow the specific grammar when we speak. If the related protocol is violated, the CAN bus cannot transmit data. Generally, we commonly use three CAN bus protocols, namely CANopen, device net and J 1939, with different emphases. You can go to Baidu Encyclopedia for details. I hope my answer will satisfy you.