Research And Design Of Large LED Display System Based On ARM

With the rapid development of high technology in information age, people are more and more eager to obtain all kinds of information and display them in time. Therefore it brings the rapid development of information carrier. Light emitting diode(LED) display system is an important kind of information carrier.LED display screen uses lattice module or pixel unit made of LED to make up big area display system. For it has many features such as high reliability, long age, high performance, low cost, and more higher acclimatization, it is used in the field of the information shows and advertising of public places, such as financial market , hospital, stadium, airport, harbor, station, highway, etc.The display screen system of LED synthesizes the integrative modern new technology of the technology, such as photoelectricity, computer and control, etc. LED display screen system mainly consists of display screen, display screen controller and computer that finish characters input and show mode control. The system can show not only Chinese , English but also the figure symbol or the special figure symbol which the user appointed to. The main object researched by this thesis is the structure of hardware and software of large LED display system based on ARM embedded microprocessor.Now, 8-bit or 16- bit microprocessors are often used for the control of all kinds of large LED display screen , but because of some problems existed in these microprocessor system such as running speed, ability to address and power depletion, etc. In some complex occasions, it is difficult to satisfy large display area and thecontents of display switched frequently, aiming at the problems exists in large LED screen display system, relating to the advanced products of microprocessor, control technology and communication technology, we adopted the new generation 32-bite embedded RISC microprocessor based on ARM to constitute the forme"r level driving circuit, and PC is used to manage and control for the latter level, so this paper can form the display system easily which made up of many pieces of large LED screen display, compared with the traditional LED display system based on 8-bit or 16-bit SCM, this system can support steady display with bigger visible while no obvious increase on costs, at the same time, it can store more display contents.This reseach has mainly accomplished the content as folio wings:(1) Learn deeply about the configuration and working principle of large LED display system, analyse the main disadvantages of traditional LED display system.(2)Accomplish the whole design of large LED display system based on 32-bit ARM microprocessor, choosing the appropriate type of the main chip and analyzing the structure and the operation method of the chips.(3)Design the power circuit, crystal-vibration circuit and the reset circuit based on ARM microprocessor system, furthermore, completing the design of the systematic expansion based on S3C4510B, including mainly the expansion of the memorizers FLASH, SDRAM and the interface circuit of the S3C4510B.(4)Provide the column display driver circuit and the row scanning control circuit of the dynamic scanning circuit of the LED display screen, fulfiling the design for the dynamic scanning circuit of LED display screen and the interface circuit of S3C4510B.(5)Make a transform from LVTTL signal sent out from microprocessor S3C4510B to RS-232, which can make the LED display controllerr communicating with PC. Moreover, proceeding to design the interface circuit of 10M/100M Ethernet to provide the gateways of the Ethernet.(6)Accomplish the software design of large LED display system based on ARM microprocessor S3C4510B in order to realize display of images and letters in LED display screen. The program based on ARM microprocessor control system iscompiled with ARM assemble language and C/C++ language. The program of series communication of PC is developed with VB6.0, and the data is transferred through MSComm communication control.