CC3220SF: CC3220SF power on error

Hi team :

        We use cc3220SF as our custom board's IC.Sometimes,csutom board can't not execute code succesfully after power on,it will stuck in strange status.But sometimes everything is okay.

        For example, we use sample code "buttonled" as template,we modify code as below.

        void *mainThread(void *arg0)`

        {

                 GPIO_init();

                 GPIO_write(GLED,0);

                 sleep(1);

                 GPIO_write(GLED,1);

                 return 0;

        } 

        If code is execute succesfully,led will light on 1s after power on,But sometime device is not light on LED after power on.     

        we also check clock ,and compare with datasheet , custom boards looks like stuck in "FW INIT" status and "APP CODE LOAD" status.

    so I want to ask some qustion,

    1.Is there any FW setting we need to do about power on,or any setting will let device stuck in strange status (maybe bootloader point incorrectly or driverlib call incorrectly) ?

    2.RTOS will cause this problem?

    3.Project property need to do some extra setting?

    4.Any setting we need to do to let device run in Wide-Voltage Mode not in Preregulated 1.85-V Mode (Because our HW design is reference to Wide-Voltage Mode)?  

    5.Any other problem will cause this problem.And any method can resolved this problem?

Best Regards,

Smith Wu.