Baud-rate automatic matching method for controller and CAN bus

Abstract

Disclosed is a baud-rate automatic matching method for a controller and a CAN bus, that is, a plurality of kinds of standby standard baud rates are stored in the controller and the controller is connected to the CAN bus; the default baud rate of the controller is set; the controller receives a message sent by the CAN bus; whether baud-rate matching is successful is judged according to whether the message sent by the CAN bus and received by the controller is correct; if the message sent by the CAN bus and received by the controller is incorrect, values in a built-in error count accumulator of the controller are accumulated; and whether to execute resetting of the baud rate of the controller is determined according to whether the value of the error count accumulator reaches a preset value. The method realizes baud-rate automatic matching between the controller and the CAN so that the controller is applicable to CAN buses of different fixed baud rates and universality and transportability of the controller are improved.

Description

Technical field [0001] The invention relates to the communication field of automobile electronic control systems, in particular to a method for automatically matching the baud rate of a controller and a CAN bus. Background technique [0002] As consumers' requirements for car performance and comfort continue to increase, the number of electronic control systems in cars has also increased accordingly. Controllers need to be connected to each other through a communication network. The most widely used interface is the CAN bus. Monitor and manage each controller through CAN bus. [0003] In the traditional communication method, the two parties communicating must have the same baud rate to be able to communicate normally, and the mutual communication between the car controller and the CAN bus must also have the same baud rate, that is, the controller can only It communicates with a specific CAN bus with the same baud rate as its own. In practical applications, the baud rate of the C...

AI Technical Summary

Problems solved by technology

In practical applications, the baud rate of the CAN bus is not unique, and different CAN buses have different baud rates, and usually the baud rate of the controller has been fixed in the factory, resulting in when the controller is transplanted to a different When the baud rate is in the CAN bus, not only will there be a situation of inability to communicate, which will limit the versatility of the controller, but also when there is an error frame on the bus, it will even cause the CAN bus to be paralyzed, and the rest of the controllers will not work normally.

At the same time, the diagnostic instrument cannot reconfigure the baud rate of the controller. The only solution is to replace the controller with a new one.

This not only wastes resources but also increases costs and reduces work efficiency.

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