Real-time Multi-tasking Technology-based Pc-cnc Tension Machine

As PC is used widely, more and more software systems begin to move from the large computers and special hardware to PC platform. The advantage of using PC as the foundation to develop application is that there is a lot of software based on PC. In this kind of background, we develop the Bending Machine numerical control system. Real time and multitask are the key technologies which are used in the Bending Machine numerical control system. The function of the real time and multitask would influence the stability and security and effectiveness of the whole system greatly.In this thesis, the author not only researches how to control the Bending Machine in real time, but also discuss how to implement the multitask mechanism in the Bending Machine numerical control system. Real time is necessary to the machine such as Bending Machine. It has strict restrictions upon time. The author will discuss this problem in several ways, one of them is to apply VxD (virtual x device driver), one is to use the high precision timer in the Bending Machine numerical control system, another is to use WinDriver to develop real time driver for WINDOWS 2000 and WINDOWS XP. These approaches are used together to control the Bending Machine in real time. The multitask mechanism of the Bending Machine numerical control system is designed in the foundation of the WINDOWS 98 operation system' s multi-thread mechanism. So this application not only has a multi-thread model, but also has a characteristic multi-task management mechanism in order to develop an individual system.Nowadays software engineering is more and more important in the software industry. In this thesis the author also has used the advanced software engineering technology in order to build high quality software system. The United Modeling Language (UML) is used effectively during the software analysis and software design phases. The author has made use of UML to establish the functional model, the static model and the dynamic model of the software system. Through the UML models the author visually display the software design blue print.During the software realization period, the following developing environment has been used: Software environment: WINDOWS 98 + Visual C++ 6.0 Hardware environment: the EVOC Industry Computer + Omron PLC...