Programming method of CAN-LonWorks protocol conversion logic

Abstract

The invention relates to a programming method of CAN-LonWorks protocol conversion logic. The method includes: defining operators and the priority of each operator; defining the only digital code corresponding to each protocol variable; using operation number and the operators to compile the explicit assignment expression of each protocol variable according to CAN-LonWorks protocol conversion requirements and through operator rules; performing compression conversion on the explicit assignment expressions to encode the explicit assignment expressions into implicit assignment expressions; inspecting the implicit assignment expressions, determining that the inspection is passed if the implicit assignment expressions are correctly analyzed, and adding ending tags 'END' to the tails of the assignment expressions. The programming method programs the conversion logic according to needs to adapt to different application occasions.

Description

technical field [0001] The invention relates to a programming method for CAN-LonWorks protocol conversion logic. Background technique [0002] CAN is an ISO international standardized serial communication protocol. CAN bus is widely used in the fields of automobile and industrial measurement and control because of its good anti-interference and low cost. The CAN bus protocol provides the OSI reference model three-layer protocol (physical layer, data link layer and application layer), and defines the physical layer and data link layer. The application layer protocol is defined according to the application object. The data frame format of the CAN protocol is as follows: figure 1 , including 7 parts: Start of Frame, Arbitration Field, Control Field, Data Field, CRC Field, ACK Field, Frame End of Frame. Among them, the frame start, CRC field, response field, and frame end are automatically completed by the CAN controller, and the arbitration field, control field, and data fie...

AI Technical Summary

Problems solved by technology

The existing protocol converters focus on the conversion of the two underlying protocols of the bus, and only convert the CAN protocol and the LonTalk protocol, without considering the variety and variety of the application layer protocols, and not paying attention to the connection between the two protocols. Complex logical relationship, that is, the complex logical relationship between the format of the LonTalk protocol (message type, data, etc.) and the format of the CAN protocol (frame type, frame format, identifier, data, etc.) is not converted, it can be considered completed It is only a transparent transmission between LonTalk protocol and CAN protocol, and its conversion logic does not support modification

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