Design Of A Programmable Logic Controller Based On Embedded STM32

In recent years,with the rapid development of the national economy in China,the speed of the development of the mining field is also accelerating.The application of mechanical and electrical equipment in the excavation and management of coal mine is becoming more and more extensive,and the requirements are also increasing.Programmable logic controller is more and more widely used in coal mine electromechanical system.The mechanical and electrical equipment based on PLC should meet the needs of coal mine production safety.It must be examined by the national security department,and the review needs to provide detailed PLC complete sets of circuits and components.Due to this requirement,the general commercial PLC manufacturers can not satisfy the reasons for technical secrecy.In view of the above problems,this article designs a PLC system based on ARM,which can meet the needs of electrical control,and is equipped with the corresponding circuit schematics,component lists,PCB production drawings.It has brought great convenience to the process of submitting trials and played a positive role in the development of the mining industry.The PLC is based on a PC and uses software to finally realize the functional characteristics of the traditional hard PLC under the working environment of Windows.Embedded PLC has better compatibility and open features.This subject is based on the basic knowledge of PLC and the basic principle of embedded,researchs and designs a soft PLC design system based on STM32F103x chip.This text regards STM32F103VCT6 as the central processing unit(CPU)of embedded PLC,sets up the hardware circuit of every module of embedded PLC with this microprocessor(MCU)as the core.The corresponding hardware is printed according to the corresponding hardware circuit diagram,and the relevant hardware debugging of each function module is carried out.Keil software is used to design the lower position soft PLC drive system.Implement the basic definition of the embedded PLC architecture and design the functional function of each m designodule,such as input and output design,serial communication design,and so on.Then write,debug,and correct for each module until the code is correct.The lower machine driver function is downloaded to the embedded PLC through the serial port,and an embedded PLC system is constructed.Finally,it introduces the basic principles of Modbus communication protocol,and uses GX Developer software to compile,modify,and save Modbus ladder diagrams and instruction lists of embedded PLCs,writes and reads Modbus ladder diagrams,and implements online monitoring functions.Complete the conversion between the ladder diagram of the embedded PLC and its instruction list.Through the application of Modbus Ladder Diagram in embedded PLC,communication between Modbus upper computer software and embedded PLC,the feasibility of embedded PLC development is verified.