In reply to vennela.adavelly:
I do not understand your complains. It works in my environment and I see the pinlevel interfaces toggeling after doing a few changes:
(1) remove the $finish in your testbench file
(2) replace the forever loops in your sequence. If there is a forever the simulation will never stop.
But I see many errors.
And there are more errors inside. You are using clocking blocks but synchronizing on the clock edge instead. This might cause more serious errors.
