Design And Development Of Display System For Bus Station Broadcast

Bus is an important part of urban public transport.In the process of bus operation,the station must be broadcasted in order to prompt the necessary information to passengers inside and outside the bus.As the environment inside and outside bus is noisy,the necessary station broadcast text and the visual cue of station broadcast picture is particularly important.Although the traditional station broadcast equipment have the function of LED screen text display,there are some questions,for example,the function is single,interaction is not enough,and it is difficult to maintain.this thesis designs and develops a display system for bus station broadcast,which has dynamic update function of station information based on LCD screen,multi-mode display function of station broadcast text based on LED screen,information interaction and device status query function based on Bluetooth and WeChat.The main work of this thesis is as follows:(1)Describe the research background and significance of this topic,analyze the current research situation at home and abroad,and give an overview of the technology that may be used in this article.At last,the main contents and structure of this topic are outlined.(2)The system uses DM365 video chip as the core to realize the play of external composite video signal,uses TrueType vector font library and FreeType font rendering program to realize the display of the station information,designs the message communication protocol among modules to realize the updating of the running route and the receiving of station information.(3)The hardware circuit of LED display board based on STM32 MCU is introduced.Based on the ?C/OS-II real-time operating system,various software task modules are designed and developed.Finally,static and dynamic display of station information,the priority display of service text display and the process of the external message is realized.(4)In order to facilitate the interactive query of the station information for passengers,and to facilitate the daily management of the station broadcast equipment maintenance personnel,a data passthrough module based on Bluetooth and WeChat interface is designed and developed.This module takes CC2541 chip as the core,transplants the AirSync protocol of the WeChat and realizes the serial port passthrough protocol with the main processing chip on the basis of TI BLE Stack.(5)Summarize the whole thesis,and make a further prospect on the improvement of the system.