A programming method of can-lonworks protocol conversion logic

Abstract

The invention relates to a programming method for CAN-LonWorks protocol conversion logic, comprising the following steps: defining operators and defining the priority of each operator; defining unique digital codes corresponding to protocol variables; according to CAN-LonWorks protocol conversion requirements, using Operands and operators, and formulate the explicit assignment expressions of each protocol variable through operator rules; compress and convert the explicit assignment expressions, so as to encode the explicit assignment expressions into implicit assignment expressions; The assignment expression is checked, if the parsing is correct, the check is passed and a line of end mark "END" is appended at the end of the assignment expression. The programming method of the CAN-LonWorks protocol conversion logic provided by the present invention performs on-demand programming on the conversion logic to adapt to different application occasions.

Description

technical field [0001] The invention relates to a programming method of 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, and 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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