Design And Implementation Of Digital Control Application Software System Based On MODBUS Protocol Stack

Through the research of the MODBUS protocol stack,application for the commonly used RTU and ACSII mode in MODBUS communication under, in particular Industrial CNCstepper motorcontrol applications, to complete the design and development of MODUBS protocol application softwareand the lower computer platform based on.The influential industrial conventional adopted in NC technology stack and domestic, foreign companies such ascontrol, ABB, Siemens, Schneider Delta, the factory in the programmable controller(PLC) and the industrial display(touch and text) communication protocols are studied, further indicated that the MODBUS protocol is an application layer communication an open, various industrial enterprises have been expanded certain depth and width in the standard MODBUS protocol stack based on.Aiming at the control of stepper motor, developed a set ofcontroller based on STM32F103VCT6 main chip, using SP3232 and MAX3485 as the serial communicationinterface, realize the communication function of RS-232 and RS-485, the software is developed by C languagesoftware, implementation of MODBUS communication protocol module and timer function of stepper motor control module. In the upper part, this paper mainly introduces the text, touch screen and VISUAL BASIC.60 development platform of two kinds of man-machine interactive mode. In the text and touch screen in the industry, development of software platform automatically, through the configurationmode of development the corresponding display interface; in VB development software, using visualization softwareplatform and based on object programming model, through the platform with MSCOM control system, realizes the PCserial port and based on MODBUS protocol.In the establishment of the MODBUS protocol stack as theresearch object, according to the specific application in the field of CNC stepper motor control, development based on a multi axis step, lower machine control system, mainly studies the key content:(1) research and extension function of MODBUS protocolstack;(2) the configuration system based on text, touch screen;(3) the understanding of STM32 series AMR chip based hardware, and study the C language development through this platform, mainly to complete the protocol stack software implementation, the external input and output interfacemodule, timer stepper motor control procedures, and complete the corresponding motor linear, circular function code realization;(4) computer visualization, object based programming VB 6 development platform and the corresponding softwaredevelopment.This topic design and Research on the content and system,will finally realize the slave system, application andnumerical control equipment such as: engraving machine, automatic feeding device and lock core processingequipment is debugged and a series of experiments, thesystem has certain application and practice in the field of CNC machining.