Hello,
PFI Lines are explained in the user manual of the card you have. So depending on which card you have, I would suggest you to take a look at its manual for detailed explanation.
You may also want to take a look at the support page to find many articles on example programs using the PFI lines:
Keywords Search: pfiSincerely,
Sastry Vadlamani
Applications Engineer
National Instruments
Message Edited by Molly K on 02-19-2005 12:08 AM