Greetings,
Below is a link to a KnowledgeBase, which discusses your options:
http://pong.ni.com/public.nsf/websearch/F3009806E2AE416E8525645D0076B962?OpenDocument
It appears that Advantech has a LabVIEW driver available. Below is a link to information about the driver on their Web Site. I would suggest trying this option, as opposed to using the Call Library Function with Advantech's driver DLLs:
http://www.advantech.com/content/0000000175/0000000175.asp?css=corp&name=corp
Good luck with your application.
Spencer S.