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The general industrial controller is the heart of modern automatic manufacturer. With theshortages of low performance-price ratio, high complexity, in medium and small sizedenterprises, it is not profitable that small-scale production does not need the general industrialcontroller. So a lightweight industry controller system with the characteristic of highperformance-price ratio becomes to be the focus of researchers.In this work, based on the principles of industry controller, a industry control system isdesigned, which is based on ARM Cortex-M3framework (lower computer) and WinCCconfiguration software (upper computer). In order to meet small-scale, small-amount andshort process flow requirements in production process, this design aims at stableconfiguration monitoring, control protocol compatible and friendly user interface. A designschema, which increase the production efficiency, decrease the cost, WinCC compatible, isfigured out.In this design, three aspects is mainly considered:1. The data acquisition and control (DAQ) module: in this module, ARM Cortex-M3CPU STM32F103x is selected. The working frequency of this chip is72MHz,512KB flashmemory,64KB SRAM, three12bit ADC and two12bit DAC,112GPIO pins, every GPIO pincan mapping to16external interrupt. This module have8channel digital I/O per unit,8channel analog input per unit,2channel analog output per unit and serial port. Thisconfiguration is suitable for the application requirements.2. The interface circuit of DAQ module: this module is designed for optical-electronicisolation, voltage matching, signal transform, communication and power output. Under the3.3V working voltage, TLP521-4(digital), HCNR201(analog) and6N137(signal) areselected for optical-electronic isolation and voltage matching. MAX1483is selected forcommunication. ULN2804(digital) and THS4001(analog) are selected for signal transformand power output.3. The WinCC OPC Server: this server is used for communication with the WinCC OPCclient, based on STM32F103x control structure. The OPC server is an open interface for process communication, which is based on the standard of OLE for process (OPC) protocol,can solve the application compatible problem on different controllers.
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