CAN protocol communication converter and method applied to Mitsubishi FX type PLC

Abstract

The invention provides a CAN protocol communication converter and method applied to a Mitsubishi FX type PLC. The converter mainly comprises a PIC18F25 core board, a power supply module, an encoder module, three dial switches, a serial port and a CAN interface. Via the converter disclosed in the invention, PLCs of all models of Mitsubishi FX series can be accessed to a CAN bus network through a universal serial port without a CAN communication extension module, so that conversion between a CAN communication protocol and a Mitsubishi PLC special protocol is realized; the CAN communication parameters and the serial communication parameters are set by adopting the three dial switches, so that an operator can adjust the parameters of the communication converter according to the actual situation, the use is convenient and flexible, and the operation is simple.

Description

Technical field [0001] The invention belongs to the technical field of CAN protocol communication converters, and particularly relates to a CAN protocol communication converter and method applied to Mitsubishi FX PLC. Background technique [0002] As an 8Bit microcontroller, PIC18F25 has a maximum operating frequency of 64MHz, an internal program memory size of 64KB, and a wealth of peripherals. It integrates an ECAN bus module that conforms to the CAN 2.0BActive specification and has 2 UART modules. In view of the high reliability of the chip, low power consumption and special support for CAN communication, it is currently widely used in industrial control, communications, Internet of Things, and automotive electronic equipment. [0003] CAN is the abbreviation of Controller Area Network, and it is one of the most widely used field buses in the world. Because of its high performance, high reliability and high flexibility, it is widely used in industrial automation, automobiles, sh...

AI Technical Summary

Problems solved by technology

PLC is a controller specially used for industrial control, which can execute user-oriented instructions such as logic operation, sequence control, timing, counting and calculation operations. Mitsubishi FX series PLC is widely used as an affordable small and medium-sized PLC, but Due to the limitation of the communication interface, the networking method based on the general-purpose serial port can only be used without an external communication expansion module. This method has great limitations and is difficult to adapt to the requirements of the modern industrial Internet of Things.

If an external communication expansion module is used for CAN networking, firstly, the development cost will be greatly increased, and secondly, the types of CAN bus expansion modules available for FX series PLCs are very limited, and many small PLCs of FX series do not have CAN bus compatible with them. Expansion module; even if the CAN bus can be used to expand the module network, it is limited by the complex protocol format of Mitsubishi PLC, and the communication efficiency is very limited when interacting with other brands of equipment.

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