The Design Of Data Receiving And Dispatching System Based On USB

While the fast development of modern technology and the needs for earthquake study,earthquake observation and earthquake warning,instrument and equipment of modern earthquake observation has been improved a lot, especially the rapid development of computer technology,it introduces the instrument and equipment of modern earthquake observation into the phase depending on computer.Data acquisition technology is a synthetical application technology based on technologies of sensor,signal measure and disposal and computer,and it studies on data acquisition,memory,disposal and control,etc.it includes analog signals modulation,analog signals digitalization,digital signal processing and so on,so it is greatly useful.USB(Universal Serial Bus) technology is widely used because of convenience,engrossing less system resource.The goal of USB(Universal Serial Bus) technology is that it solves the jam in outside equipment of the PC and improves the transport rate for the purposes. USB only needs little simple installation and setting when it use outside equipment.It offers the function which when you insert the outside equipment to the PC,you can use it immediately and the function of hot inserting which you can connect the outside equipment to the USB at first hand and then it can be identified and used by the system at once when the power supply has not been cut off.If it is possible to invent a equipment of earthquake observation which can gather,process,analyze earthquake data by applying interface technique of USB, it will has the very vital significance to our country's digitized earthquake constructionv.On the basis of comprehensive research about USB correlation technique,a system possessing the characteristics of data collection with high speed, processing is designed.This system depends on the main control of monolithic integrated circuit MSP430 to fulfill data collection with preprocessing,high rate transmission by USB and the final data processing in computers.The specific content of studying is listed as follows:This paper deep research the correlation theories of USB technology, including:the composition of USB system,the level of USB system,as well as the differences among the four data flow types that consist of data pattern, transmitting direction,the capacity limitation of data pocket,and the bus interview confinement.Finally this paper research the USB business treating processes,the examination process of USB equipment.This paper make the simple introduction of USB chip FT245BM which used for this article,mainly includes the characteristic of this chip,the chip pin,the chip function,as well as the data transmission method of chip and peripheral device.This paper gives the explanation of the monolithic integrated circuit MSP430 which used for this article,includes chip characteristic,chip pin,chip function,based on this,this paper designes the hardware circuit of this system, mainly includes the MSP430 core circuit design,the USB chip circuit design,the power circuit design,the reset circuit design,the crystal oscillator circuit design and so on.The key point of this article is that it designs and realizes the software of this system,might complete through the software to the USB chip search,the connection,as well as the control of each data transmission.In the design of the software part,first API function of FT245BM has carried on the seal,then several big functional modules has made the detailed design.Finally,an experiment about the content in this paper is carried out.The experiment statistics reveal that the operation of this system is steady and the functions such as high rate data collecting,reliable transmission and processing are well fulfilled.