Please advice for USB interaction

Hi tech-misc

I hope that you can help me, somehow.

I'm an engineering student trying to build a "data aquisition module"
using USB and Unix (netbsd in particular) but I'm a bit lost.

Imagine this:  I have an analog signal (for example this signal varies
between 0 and 3v) and I need to record in the PC the voltage of the
signal every 2 seconds (or every 2 ms). Then record this information,
for example, in a simple text file. I would like to use netbsd and the
USB port for this.  Is there any directions that you may give to me on
how to achive this task ?

--
Marco Ferra
[email protected]