Hello Lei Gu,
I am sorry that I can not test the firmware because I don't have the hardware.
I usually plays with Sensorless firmware for F28027 (HVACI) and they works just fine in flash.
Is there any warning after building?
Did you set any breakpoint in your firmware? If so, please remove all breakpoint.
Have you ever tried to run without debugger, does your motor run?
Maybe you can try HVACI Sensorless F28335 for flash debugging (Build Level 1, without motor connected) to see whether the same behavior occurs.
For Gautam, do you have F28335 to try? Or other people?
Really hope you can solve your problem.
Best regards,
Maria