The Design Of Touch Screen Control System Based On FPGA

With the rapidly growth of science and technology, the touch screen has presently become the main input equipment in public occasions. It is taking place of traditional input equipments such as the keyboard and the mouse, the way of Human-Computer interaction have become the hot spots in domestic and abroad, and its easy to use, strong, fast response, a space-saving advantages make touch screen a broader application prospect. FPGA is used to design and product digital integrated circuit, it has been developed quickly since 1970s. FPGA has the characteristics of unparalleled flexibility, real-time design process and can be reprogrammed, so it has been widely applied in the field of electronics and communications.This paper implements the idea of touch screen control. A new idea of controlling touch screen by combining hardware and software based on FPGA is provided. Firstly, the touch screen technology and its development situation are introduced. Secondly, the FPGA's main characteristics, structure principle, programming technology, development flow and development trend are described, then the ISE system development platform and hardware description language (VHDL) are introduced, particularize the Virtex-II Pro FPGA devices which is used in this paper. In the latter part of the paper, the development process and key steps in touch screen control system are researched. Different kinds of touch screen principles are analyzed, and mentions four-resistance touch screen in particular. Then the ADS7843 chip used to control touch screen and its characteristics, structure, function and work mode are described. Finally, according to the relevant knowledge, the touch screen controller is designed, then under the Xilinx ISE, develops the main module of the system, gains the overall system simulation and proves this system can operate normally.