Usb Bus-based Portable Data Acquisition System Design

Universal Serial Bus (USB) is one of the most important developments in PC peripheral interconnect technology since the introduction of serial and parallel ports in the early 1980's. The USB have lots of benefits, such as ease of use, true plug and play, high performance, and reduced overall system cost. At the same time, Along with the development in PC bus technology, Modern Virtual Instruments have the characteristic of miniaturization and portability, Basing on the improvement of the working ability . Therefore the concept of USB Bus Virtual Instruments has appeared. Based upon this concept, the author designed Bus Portable Data Acquisition System Based on the USB . During the design, combined the USB 1.1 technology with the data acquisition technology, fused the concept of Virtual Instruments in this article. The author adopted some technique, such as the CPLD design, the parallel-channels acquisition ,the WDM driver programming and so on.There are two parts in the article : in the first part, the author expatiates the concept of USB Bus Virtual Instruments and the theory of data acquisition. In the second part, the author describes how to design a USB Bus Portable Data Acquisition System in hardware and software, makes a detailed requirement analysis and gives a whole frame design of the system.