Writing a Main program to test UMAT

Hi Mechanicians,

 I have written a UMAT for single crystal plasticity analysis but it is not running properly. I want to debug it. Is there anyway to do that with Abaqus? In order to debug it in a Microsoft VC++ environment I decided to write a main program for the UMAT subroutine. Does this approach seem valid? Also what type of variables should be passed into the UMAT subroutine from the Main program?  

Any help would be appreciated.

Thank you

Nitin