The USB-6501 is a portable, USB-based digital I/O module that is powered via the bus and enables cost-effective, reliable data acquisition, control and regulation. The module offers overvoltage protection for its digital I/O lines and a 32-bit counter. Plug-and-play connectivity via USB makes the USB-6501 ideal for home computer and university applications, but it is also sufficiently robust and versatile to be used for laboratory and industrial applications.