The Embedded RFID Information Transmission And Display Terminal Development Based On WiFi

The rapid development of science and technology,promote the embedded application prospects constantly widened.Embedded systems generally small,specialized application.With the transmission technology leap from wired to wireless,Wi Fi technology is also further development.Radio Frequency Identification technology is a kind of no contact microwave identification technology,it can recognizes the target in a certain range,and has high accuracy and anti-interference ability.The combination of the embedded system?wireless communication and RFID technology can be used in many occasions:smart home,indoor monitor,charge system,etc.In a background of the meeting room charge sign system and in the embedded Linux system based on ARM9 platform,the topic developed an RFID card of 13.56 MHz operating system with a separation between the reading card part and the information processing part.The information transfer between the reading card part and the information processing part by Wi Fi of the system.This design is mainly divided into three parts:1)The read card and information transfer part.The main function of this part is the MCU controls the read card chip to obtain the RFID card information after looking for card,anti-collision,choosing card and key authentication.And information is sent out by Wi Fi module after format conversion.Because the controller don't need a lot of computation,so choose the control capability is strong,easy-to-play STC89C52.The read card chip selected the high integration chip MFRC500.Wi Fi part chose ESP8266 with a small size and low power consumption.A total of five card read terminal is designed of this part.2)Information processing terminal with ARM9 S3C2440 that embedded tailored Linux system as the core processor.Transplant network card drivers,key drivers,sqlite3 database,etc.For the software,Set up the server by the socket network programming based on the TCP protocol.The read card terminal that as the client get information by Linux multi-process mechanism after through Wi Fi connection to the server.The information saved in the sqlite3 database after classification and can be move to SD card by one button,verification,and important information will be displayed on the LCD screen.3)The local and remote query function.Due to the limitation of LCD screen and hardware,localqueries only through buttons to query recent information.Remote query that the PC web pages query,can by the time or the Name query information and display.This article first expounds the overall design of system framework.Then read card terminal,wireless communication module,information receiving,storage,display,query module has carried on the detailed instructions on the hardware and software.In the design,first of all one read card module is tested,then access the five read card modules.After a lot of modification and operation of software debugging,and ultimately the system can accurately read card information,can also be stable for information storage,display,query.