Calling ISR function

Hi,
Is it possible from startup.asm I can call the interrup service routine found in my C source file?

from my C source file:

void InterruptServiceRoutine (void) interrupt 7 //SMB
{
    ...
}

In my startup.asm:

   ...
   EXTRN CODE (InterruptServiceRoutine)
   ...
   ljmp InterruptServiceRoutine

Your response is greatly appreciated.

thanks
gilmar