HardFault and UsageFault detected by IAR Interrupt Log

biloy wrote on Friday, September 11, 2015:


I am using FreeRTOS on LPC1833. I’m using IAR and I-Jet debug probe. My program run well.

By curiosity I found the Interrupt Log window and Interrupt Log Summary while debugging. It shows in which interrupt the software enters and leaves.

The thing is that I’m surprise to see that, according to the Interrupt Log Summary, my program enters/leaves in/from the HardFault and UsageFault interrupt ! and a lot of times! But when i set breakpoints in the respective IRQ handler, the debugger never stops.

I’m wondering if is this just a debugging/display problem from IAR.

It happens after the FreeRTOS scheduler starts. I try to not create my freeRTOS task and let only the Idle task but i have the same strange issue. If i just initialize by board, peripheral, and do a while(1) I don’t see HardFault and UsageFault.

Do I have to consider that as a problem from de debugger?



rtel wrote on Friday, September 11, 2015:

FreeRTOS does not expect to enter a hard or usage fault handler. If the fault handler is just a null loop, then if it did enter it, it would never exit again.

I suspect this is either just an error or misinterpretation in the log file, or that the IAR tools themselves are using these exception handlers.