The development of a data acquisition card based on USB bus is introduced in this article.It first describes the configuration and principle of this card in the part of hardware design,and then the application program and device driver in the part of software design.Data acquisition program in firmware is also discussed.Finally,this data acquisition card is tested and evaluated in a program developed by Lab Windows CVI,which shows that this car is stable and reliable
Universal Serial Bus (USB) is a communications architecture that gives a personal
computer (PC) the ability to interconnect a variety of devices using a simple four-
wire cable. The USB is actually a two-wire serial communication link that runs at
either 1.5 or 12 megabits per second (mbs). USB protocols can configure devices
at startup or when they are plugged in at run time. These devices are broken into
various device classes. Each device class defines the common behavior and
protocols for devices that serve similar functions. Some examples of USB device
classes are shown in the following table