Study On The Key Technology Of Real-time Control In Serial CNC System Based On Windows

The paper synthetically studies the key technology in software development of real-time control system based on Windows, and emphatically analyses correlative technology, which applied on software development of real-time serial communication base on Windows. In the end, the paper study on several control function in NC (numerical control) system.Chapter 1 presents a review of the integration of NC system, and introduces the developmental trend and main characteristic of modern NC system. And then, the charpter analyses system framework of open architectural CNC system based on PC and mainstream software platform of NC system, and expatiates significance of study on economic SCNC (Serial Computer Numerical Control) System base on Windows. In the end, it presents the paper's content.Chapter 2 contraposes to the key question of real-time multitask NC system based on Windows, and study the precision timing technology used software or hardware under Windows. On the basis of analyzing characteristic and theory of device driver under Windows and studying the key technology in the programming of virtual device driver, puts forward the realization of sharing memory between application and VxD. Furthermore, Synchronous mechanism, task schedule rule and thread schedule model of multithreading technology in Windows are studied deeply.Chapter 3 introduces the characteristic , composing and data transmission mode of compunication system firstly. Secondly, it analyses and compares capability characteristic and application situation of three kinds of standard which applies computer serial communication interface(RS-232Cx USB and IEEE-1394) . Finally, the technology of data link control protocl, such as flux contro, error control which apply on communication protocol hiberarchy, is analysed and studied.Chapter 4 introduces deep mechanism and primary process of serial communication in Win32 system, and analyses the way of programming and wok mode of serial communication. On the ground of analysis and study of the main technology of realizing serial communication based on Windows API and VxD respectively, real serial communication software is developed. Finally, experiment and analyze what is correlative factor, which affect real-time serial communication.Chapter 5 simply introduces the composed of SCNC system and its structure of software and hardware. On the basis of analyzing characteristic of real-time multitask control in NC system base on Windows system, it gives buffer technology on the control of multitask and real-time schedul scheme which bases on multithreading technology. In the end, it studies and develops several control function in NC system. Chapter 6 summarizes the study of entire paper, and prospects the development of open architectural CNC system.