Dtu Design Of The Usb Interface

In this paper, based on the analysis of current situation and development tendency of short message transmission device, according to condition, the design scheme and realization method of a DTU with USB Interface is put forward, which utilizes "the USB technology" and "the short message technology" being now two very popular techniques. This design is a short message's wireless Data Terminal Unit (DTU), which consists of computer technology, the GSM network technology, the single-chip technology and the USB interface technology. This design utilizes System-on-Chip MCU--Cygnal's C8051F320 as the control core, and acts Siemens Corporation's industry level communication module TC35i as the transmission core.This data which host sends to DTU by USB interface is send to another data terminal as a GSM network short message.This DTU receives the short message from the GSM network and transmits it through the USB interface gives the host. It is used in setting up point-to-point or the center to the multi-spots wireless, data transmission network, which realizes the long-distance transmission and gathering or the monitor in a wide range.In a word, this system has a great practical value.In order to develop successfully the short message transmission device based on the GSM network, the paper introduces firstly the knowledge of GSM network in brief, and introduces AT instructions in detail which can operate the short message and PDU ecoding & decoding process of DTU.In order to apply the USB technology to the short message transmission device, the paper introduces briefly the relative knowledge of USB network, and introduces strongly the development process of WDM driver.This design includes hardware and software design. The hardware design part introdu -ces firstly the characteristic and performance of C8051F320 chip and the TC35i module which are used in the design application, then produces the concrete hardware design scheme, and notes those questions in the design emphatically.There are three parts in the software design part,such as the firmware's development, the driver development program and the application program development. The paper shows the idea of program design and the programming structure and then introduces program flow diagram and gives a few codes of the firmware program. In the driver segment, the driver development environment, the driver structure, the process of development and the realization method is introducd.The application program mainly includes the design of a friendly man-machine interface, the PDU ecodng&decoding and the short message's transmission aswell as the telephon book mangement.