The Development Of A Special Programmable Logic Controller

Programmable controller plays a very important role in modern industry . It is called as one of the three pillars of modern industry . Based on studying deeply the propties, the structure and the operational principle of programmable controller,the thesis shows how to develop the special programmable controller with single chip microcomputer system. The applications of the programmable controller to the electrical control of wirecut electro-discharge machine(WEDM) and traffic control are illustrated in detail.The main results of the thesis are shown as follows:1.The overall structure scheme of the special programmable controller is presented.2.The hardware and software of the special PC have been designed and debugged successfully .3.How to design and programming the monitoring system are discussed,also the frame and format of the PC directives are illustrated.4.The functionally modular construction,the principle of the compiler and the methods to perform these functions in C-language are depicted in detail.The technique of object-oriented programming(OOP) have the system the features of succession,expansibility and obturation.5.Based on the analysis of the relationship between the ladder diagram and the directive commands,the visual programming skill is adopted to the compiler of the special PC.6. Various antijamming measures in the hardware and software of the special PC are taken for improvement of the reliablity of the system.7.The serial communication between PC and micro-computer is accomplished.