The design of LCD controller and its improved application based on FPGA

摘要

The principle of color LCD (Liquid Crystal Display) is similar to raster scanning display. The data of the frame buffer is scanned to monitor from left to right and up to down under the controller. The special display controller is supplied by the manufacturer, which is not common and lack of expansion. Under system analysis of the scanning sequence and controlling mode of color LCD, the design of LCDC based on FPGA and the benefits of double frame buffer were combined. The display mode - one-frame-two-scan, can double system bandwidth and maintain the display quality at the same time. Moreover, a method of graphics superimposed display and complex graphics dividing into two parts to render and display were proposed without any additional hardware. These novel methods can process different graphics data from two sets of frame buffer. The control sequence based on FPGA was realized by VHDL. Simulation waveform in ModelSim was also presented. Practical application shows that one-frame-two-scan can obtain 50Hz field scan frequency at 25Hz frame frequency. Ways for graphics superimposed display and complex graphics dividing into two parts to render which can double performance of the graphics processor.