You are probably missing the infinite loop that keeps the cpu running. When main() ends, quo vadis ???
Next time can you please post your complete project, so that we all can have a look at all of your settings. To do so, use
Creator->File->Create Workspace Bundle (minimal)
and attach the resulting file.
Thanks for the reply.
Of course I missed the infinite loop, but that wasn't the reason behind not executing the ISR.
Actually the ISR is executing, however the PWM_Stop() command was not working. It is ok now.
My bad, sorry!