Linux-based Liquid Crystal Display Drive Technology Research And Application

LCD panel is applied widely in our daily life and production. In this paper, the LCD driver and application is described based on the actual production of electrolytic aluminium factory, which can also be transplanted into other related systems.The realization of the Linux LCD driver is based on FrameBuffer. FrameBuffer is a driver interface. Such an interface can abstract the LCD device into a frame buffer, in which the operation to the buffer of the application program is the operation to the LCD screen. FrameBuffer device driver is the standard characters, not only to realize the operation of the hardware function, but also to configuration parameters according to the information of the LCD panel.In order to verify the LCD driver, this paper also implements a drawing software. The drawing software is based on Qt and the major function is to achieve the drawing of the electrolyte temperature decline curve and the searching for the primary crystal temperature. When the Qt program gets temperature data from the system, the first step is the smoothing for the temperature data and deletion of the unreasonable data, after which the temperature data are stored and the data drew on the LCD screen in real time. In the process of curve drawing, the second derivative method makes a judgment to the real-time plotted data, then filter and find out the numerical values which can satisfy characteristics of primary crystal temperature points. Such points are tentatively called candidate points. After the process of dot density method to these candidate points, algorithm will find the true primary crystal temperature point.In conclusion, the primary crystal temperature point obtained in this system has a high practical value and plays a vital guiding significance to the practical production. LCD driven research and application has a powerful portability, which can provide some certain reference value to similar systems.