Technical Field
The present disclosure relates to a multi-protocol determining method. More particularly, the present disclosure relates to a multi-protocol determining method based on a control area network (CAN) bus.
Description of Related Art
There are many types of commercial vehicles, such as light or large buses, light or heavy truck, and estate cars. Such vehicles are produced in USA, Japan or Europe, and use ISO protocol or SAE protocol.
However, new vehicles produced in USA are regulated to use the CAN bus interface from 2008. The vehicles have to provide an On Board Diagnostic II (OBD-II) connector, and the heavy duty vehicles has to be communicated based on SAE-J1939 while other vehicles are communicated based on ISO-15031/SAE-J1979. Moreover, new protocol, WWH-OBDII, has been developed, and some new vehicles can be communicated based on ISO-27145. Hence, how to communicate with vehicles having different protocols is a problem needed to be solved.
Some practitioners develop a gateway which can be connected between two CAN buses, i.e., the first CAN bus and the second CAN bus, having different protocols. The gateway can receive a message from the first CAN bus with one protocol and translate the message based on the other protocol. Subsequently, the gateway can send the translated message to the second CAN bus. Since the protocols used in both the first CAN bus and the second CAN bus have to be known before translation, the usage thereof is limited.
Therefore, how to identify protocols of a communicated node of the vehicle or of a CAN bus becomes a pursuit target.