PASSING INTERNAL TABLE IN SMARTFORM

HI' I M NEW TO SMARTFORMS, MY PROBLEM IS =THAT

I'VE CREATED A NEW TYPE(SAY TY_BKPF) IN THE DRIVER PROGRAM.

THEN I'VE DECLARED AN INTERNAL TABLE OF THIS TYPE.

TO PASS THIS INTERNAL TABLE INTO MY SMARTFORM I'VE PASSED THE INTERNAL TABLE'S NAME INTO THE FUNCTION MODULE UNDER THE TABLES PARAMETER.

BUT I'M NOT ABLE TO UNDERSTAND AS TO WHAT TYPE SHOULD I GIVE IT IN THE FORM INTERFACE IN THE TABLES TAB.

PLZ HELP.