Research And Development Of The Embedded Wireless Information Bulletin Screen

With the acceleration of society's informationization and the improvement of people's living standards, people have various means to acquire information and a growing demand for a good quality of life. The former information bulletin mode seems extremely simple, and it is out of date, and the intelligent information bulletin mode has become a new trend. People should abandon the old blackboard mode or poster mode, and adopt the intelligent wireless information mode. Under this mode, the announcement is sent directly to the LCD screen, and the operation is convenient, the overall design is attractive and intelligent, so it will greatly facilitate the acquisition of bulletin information. Compared to the traditional model, the new design is not only more modern, but also significantly reduced the space.The purpose of this project is to design a wall-mounted wireless information bulletin screen, used for the information dissemination or electronic billboards. This paper introduces the hardware development of the wireless information bulletin screen, as well as some appropriate driven design and application software development. System can be roughly divided into three parts:the development of PC software, hardware and software design of wireless transmission module, hardware and software design for wireless information bulletin screen's terminal. On PC, we use MFC programming to optimize the man-machine interface, edit the bulletin information and pack the date. Then according to the wireless communication protocols, we make the serial port communicate with the wireless transmission module to transmit the information. For wireless transmission module, we use STM32F103C6T6 as the core of the module, by achieving the USB Communications Device Class, we could change the serial communication of the wireless transmission module into the USB interface communication, then connect the module with the PC. On one hand, it could solve the problem of power supply for the transmission module and on the other hand, it could simplify the connection lines between the information transmission module and PC. Wireless information bulletin screen's terminal display module uses Marvell's PXA270,which is a high performance embedded processor, as the core, and expands NOR Flash, SDRAM, NAND Flash, touched screen ship, sound chip, etc externally. Then we run Windows CE4.2 operating system on it to provide a system environment for application software's running, and achieve the LCD backlight control as well as the control of wireless information transmission. As PXA270 can't drive LCD normally when the resolution is 1024*768, so we add an FPGA video acceleration module at the signal out of LCD interface to improve the video signal's refresh rate, make the LCD be driven normally and achieve high-definition displayIn this paper, a new application of LCD has been studied. The design by using the embedded processor and the video acceleration module for large-screen high-definition display is original and practical. Overall system design has important practical significance and considerable application prospect. After installation and testing, system's various indicators have reached the design requirements.