ahmedr40,
I would suggest building the FORTRAN code into a DLL as well as the breadboard code. You can then use the Call Library Function node to call the compiled code. This would be the easiest and fastest method. You could also compile these pieces of code and link them to some C/C++ code that you can write and then call this code from LabVIEW.
Randy Hoskin
Applications Engineer
National Instruments
http://www.ni.com/ask