Based On The S3c2410 Development Of Embedded Soft Plc System

After the establishment of IEC61131-3 international standard, the SoftPLC technology has a rapid development. The rapid development of computer, communications and network technologies promote the development of embedded systems which has been more widely used in the field of industrial control. At present, the embedded processor technology which is becoming more and more mature has been fully able to meet the requirements of industrial control. Thus, the combination of embedded systems and SoftPLC is an inevitable trend in the development of industrial controls, SoftPLC can be used as an embedded application running on an embedded system.First of all,this paper introduces the concepts of embedded systems and,the background of embedded SoftPLC's appearance. Second,through the analysis of the current several embedded SoftPLC solutions,this paper chooses an solution in which establish an embedded SoftPLC based on embedded controller. In this paper,the way of development is NFS. We builded a cross-compiler environment for the system they rely on, and the root file system and library the system needed to run.The object-oriented C graphic library QT is used in this paper, implement based on QT and embedded Linux system, the SoftPLC development system graphical interface, ladder diagram drawing and storage are implemented, and its editor and compiler were studied.In this paper, major work done by the following:(1)Presented the architecture of the development system of the embedded SoftPLCAnalysis of advantages and disadvantages of the current existence several embedded SoftPLC solutions, select the embedded soft PLC based on embedded controller.(2)Select the software and hardware platform of the embedded SoftPLC development system.According to the structure of the system and the requirements of the SoftPLC development system,selected hardware and software development platform, as well as the graphics library for the development of the system.(3)Build the development and running environment for development systemCompleted a Linux development environment on the host, cross-compiler installed,the installation and configuration of NFS services, ARMLinux transplant to MagicARM2410 development platform, embedded root file system, as well as cross-compiling QT transplant.(4)Use the QT graphic library to implement an embedded SoftPLC development SystemUse the QT Designer to complete the system interface development, and system components in the ladder(5) Data structure design of ladder in the development systemCompletion of an array of pointers for the ladder storage data structure design, implementation of the ladder storage algorithms.(6) On the ladder compiler research proposed ladder scan algorithmCompiler for the ladder has been studied, using case analysis of the ladder scan algorithm.