So... I also used PCI based NI (Digital&#x2F;Analog I&#x2F;O) cards in the past (around the year ~2000), which then were supported by &quot;comedi&quot; (open source linux data acquisition drivers).<p>On the other hand, I recently got a few USB based I&#x2F;O boxes from NI where no documentation on the USB protocol (or, god forbid, even open source drivers) exist.