Default_ISR during KSDK initialization

[MAPC]

Hello

My customer is working on a project with MK22FN256 and we are facing a strange problem. We noticed that we always fall into an unhandled interrupt service routine "Default_ISR", but we have no idea of what is causing it and we don't know how to see it in KDS Debugger.

His project is bare-metal and doesn't use Processor Expert.

We carefully checked out his intialization code, but we didn't see anything wrong. Default_ISR is always called at the same point in the firmware, no matter if we add or remove lines. So, any ramdom event may be causing this interrupt. Even if we disable global interrupts, the problem remains.

Can anybody help us on that please?

Bellow, we post a video showing the problem. Here you can see Default_ISR happens as we enter "CLOCK_SYS_EnableRtcClock" function, but if we insert some lines with "nop", for example, it change the point.

outdiv - YouTube

Have attached his project, for analysis purpose.

Thanks,

Marco Coelho

Applications Engineer

Siletec Eletronica

Original Attachment has been moved to: Cain_V03_00_00.rar

[Alice_Yang]

Hello Marco,

Whether the is the hardware problem , doest the 32.768 RTC work well ?

I have test you project on FRDM-K22f board , the chip is MK22FN512, it work well .

On first  built , there have one simple project , after i include the header file "#include "gpio_pins.h"" on the

file of "trata_teclas.c" , it can work well .

I also take a screenshot about single-step debug , you can check it can run well on the function of "CLOCK_SYS_EnableRtcClock" .

So i please check the hardware , you can refer to the sch of frdm-k22f.

Hope it helps

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Have a great day,
Alice Yang