Hard Fault Handler Issue

[JeffreyWedekind]

I have app_error_handler and HardFault_Handler defined - I have the WDT enabled.  My issue is if I trigger a hard fault:

// Enable divide by zero interrupt
//
SCB->CCR |= 0x10;

int HwTest = 10;
int HwDivisor = 0;
int HwTrigger = HwTest / HwDivisor;

I don't hit any break points in my code, the code stops at 0x000008c8 - the Softdevice handler.  My WDT does not fire. 

I'm trying to create a test case to catch and handle a hard fault in my code.  Any Ideas what I'm missing?  Thanks

[Einar Thorsrud]

Hi,

Edvin is OoO so I have taken over this case.

The simplest way to generate a hard fault is to dereference a pointer to some invalid memory (outside of the memory map).

Regarding the WDT I have not found any issues that would prevent it from triggering in the situation you describe, as long as it is started. The only exception is if it has been configured to pause during sleep or debug halt (see WDT chapter in PS).

[JeffreyWedekind]

Einar:  Thanks for the quick reply;

Yes dereferencing a pointer to get a memory fault - great idea.  I don't know why I had a difficult time thinking of how to generate a HardFault :).

I will re-read the WDT chapter, it must be something simple.  I will post any fixes so others can benefit from this ticket.

Jeff

[GerardB]

Hi Jeffrey 

As they say "better late than never"! :) 

I am curious to find out what/if you learnt about the how (or best way) to implement and test a fault-handler that will trigger on a divide by zero, etc..! 

Would you mind sharing what you eventually settled on (code wise)?

Thanks!

Gerard