Hi EGR!
Are you trying to using them with a cDAQ? if so, unfortunately you wont be able to do it. The DO and PFI lines are to be used exclusively with a cRIO chassis.
If you are using a cRIO, also you need to know that the PFI are input only. Ill leave you a link where all this is described:
http://digital.ni.com/public.nsf/allkb/51DD3F0206860ABC8625724B007364C9?OpenDocument
Have a great day!!
Oswald Branford
