when i set the real-time interrupting source, my appplication in xpc target can't run? why?

I use scramnet gt200 card in my computer to transfer data. And in the Matlab, I use "getxpcpci" to get the IRQ of my scramnet gt card,which the value is 11. so in the simulink model, I set "the real-time interrupting source" to "11", "I/O board generating the interrupt" to SCRAMNET GT200. Then I download the application to xpc target, but it can't run. So what's the problem? what's the function of setting "the real-time interrupting source" and "I/O board generating the interrupt"? Thanks very much!