I have located a couple of doucuments and examples that may be helpful!
Controling Parallel Port from LV:
http://zone.ni.com/devzone/conceptd.nsf/webmain/72C6FC6CE4AD4D1386256B1800794596?opendocument
Example:
http://zone.ni.com/devzone/explprog.nsf/6c163603265406328625682a006ed37d/1b8757d833164a3d862569b3001cffa3?OpenDocument
Best Regards,
Chris D