Design, Send And Receive Sms Based On Gsm Module Tc35i Wireless Terminal

Nowadays, the multi-microcomputers system, which constituted with the single chip computer and PC through the serial interface, is already widely applied in many situations such as industry control, environment monitoring and so on. These systems are mostly based on RS-232, RS-485 or wired modem. Although very economical they are, their application is limited by the wired data transmission way in very great degree. To solve the problem, the data transmission would carry on through the GSM network, in other words, the GSM engine module would be combined with the traditional single chip system, and realize wireless data transmission through the RS-232 interface.The paper is about the hot topic "single chip system controls the GSM module to receive and dispatch short messages", and elaborate the design of wireless terminal, the method of exploitation and the performance process. A GSM modem with function of short messages receiving and dispatching is realized by using single chip C8051F020 from Cygnal company and Siemens company's new generation GSM module TC35i, the foreground demo application also has been developed. The modem can realize remote data transmission between PC and the application system through this modem and the network.In the hardware design, it has completed the IGT startup circuit, the SIM card circuit, the voltage-stabilized power supply circuit and the serial interface circuit among the single chip system, TC35i and the PC. In the design of foreground application, it has completed the serial interface operation function by using object-oriented design method at first, then carried on the code of the short messages according to the PDU model, which refers to the GSM standard issued by ETSI. In the single chip system programming, it carries out the programming with the C51 language, uses the AT command to control TC35i module, and uses the way of poll inquire to read and write two serial ports.This system is especially suitable to the application of transmitting the little flux data frequently. Based on the system, it is possible to develop many kinds of applications with optimistic prospects, such as the data acquisition systems, the GPS/GSM mobile vehicles monitoring and position system, the mobile POS machine, the mobile toll system, the mobilized data and the internet connection, the computer room monitoring, the long-distance maintenance and informationinquiry system, etc. In the next step of work, using the module with GPRS function to develop the application of MMS multimedia short message service may be taken into account. It is believed that when the GPRS network becomes more perfect, the development of multimedia short message service and the execution of 3G international standard, the short message service will certainly be applied widely in other fields.