The Design And Realization Of Data Acquisition System Based On USB Bus

The topic mainly aims at the design of The DAS (Data AcquisitionSystem) with the USB interface. The DAS features with the USB lowcost, Plug and Plug, the data transmission with high, middle, low speedand so on, has satisfied the gathering request of the data acquisitionsystem.The article according to the need of design, has analyzed the USB1.1protocol, has thoroughly researched the principle of USB correspondence,the structure of USB system, the data packet form, the USB standarddescription symbol, and has proposed the overall frame design of USBDAS in this foundation. Based on the overall frame design, The DAS iscomposed by two parts: Hardware design and Software design. Thehardware design mainly constitutes by two functions modules: MotherBoard Module, Service Board Module. Mother Board Module mainlyrealized the corresponding communication between master controller(TMS470R1A256) and PC; Service Board Module mainly realized thecircuit design of data sampling, I/O expansion and so on. The softwaredesign has mainly divided into three parts: One, firmware program design witch is satisfied the system operating efficiency and the function require;Two, provides the function with the dynamic link library seal, the userservice routine for demonstration and test and the example about appliedproject; Three, introduces the equipment driver development. In thepaper's ending, unifies some actual situations which met in the process ofexploitation, proposed some suggestions for the next research, as well ashas carried on the forecast and the summary to the USB applicationprospect.The system actual plan and the theoretical analysis have built thefoundation for the following research and the development, and providethe reference for other development with embedded USB applicationsystem.