Design Of Networked PAC With Graphical Development System

PAC(Programmable Automation Controller) is a concept proposed by Craig Resnick, director of ARC consulting firm. PAC is a concept of a new generation of automatic control product relative to traditional PLC. Compared with traditional PLC, PAC has open system architecture and outstanding interoperability and flexibility. Compared with PC, PAC has higher stability and better real-time performance, thus makes PAC a better choice for industrial automation domain.Networked control system key lab of North China University has developped a PAC controller based on ARM9and embedded Linux, this system has extensible digital and analog input output module, RS232, RS485, EtherNet and many other communication method. My subject is to design a run-time system and development system based on this controller. This system would enable user to develop control program in the form of function block on PC, compiled the control program and download it to the controller easily.User of this system could also debug the control program with the development system connected to the controller, or simulate the control program offline.Furthermore, this subject also transplanted embedded web server BOA into the controller operation system and implemented a dynamic remote monitor system based on web using AJAX and CGI.This thesis firstly summarizes the development process, development status and future tendency of PAC, provides some characteristics of PAC and introduces the PAC controller platform with which this subject is based on. The second chapter introduces in detail the design and implementation of controller run-time system of this subject. The third chapter introduces the design and implementation of controller development system, including the definition of various data structure and implementation of each function block of the development system. The fourth chapter introduces the transplantation of BOA and implementation of remote monitor system based on web. The fifth chaptor introduces the online troubleshooting process of the whole system. At last, this thesis presents a summerization of this subject and gives some directions for works follow-up.Result of online troubleshotting testifies that the controller development system developped in this subject could properly compile user program into executable program file which could run on the controller platform. The development system could also fullfill the online debug and offline simulation task. Moreover, the user could monitor running status of the controller through browser.