Research And Application Of Embedded POS System Based On GPRS

Abstract:In previous retail industry, wired POS (Point of Sale) system was dominant. However, the disadvantages of wired POS system are obvious, mainly for its inconvenience in motion, poor data synchronization and the lack of portability. With the rapid development of the retail industry and the prosperity of retail chain stores, the use of wired POS system has been greatly restricted.In this thesis, the embedded POS system based on GPRS has been designed and implemented. The work mainly includes the following aspects:Firstly, a POS system developing environment is built, the POS system terminal hardware design is completed, the ARM microprocessor and GPRS communication module are chosen in this thesis, and the Qt/Embedded, SQLite migration methods are studied, which is then ported to embedded hardware platform; Secondly, to solve the data communication problems, POS system communication packet data communication is designed in this thesis, which mainly contains the control of characters, sending and replying message format, as well as the design of the communication command, communications, process design and business functions of the coding and design; AT commands manipulate GPRS communication module is used in the POS systems designed in this thesis, enabling the terminal GPRS communication function of POS server; Design and implementation of POS service side of the GPRS communication function; And timeout retransmission mechanism and power failure recovery mechanisms are made for network failures and power failures; Finally, as POS terminal server data may be inconsistent with the issues, corresponding data synchronization strategy is raised.The POS system based on GPRS communication designed in this thesis presents a good solution to the defects that traditional POS system terminal can not move whenever and wherever. Besides, thanks to the advantages of low failure rate, high treatment efficiency and fast response in use, it has been used in more and more chain retail companies.