Are you talking about the serial number of a DAQ board? The Vendor ID of our boards?
I'm guessing you are asking about the serial number. The serial number is a 6 or 7 digit hex number found on a small white sticker on the board.
You can also find this from the Measurement and Automation Explorer (MAX) as shown in the attached screenshot.
I hope this helps. If not, could you elaborate on what number it is that you need and what it is used for?
Russell
Applications Engineer
National Instruments
http://www.ni.com/support
