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Programm ends up in Dummy Handler (Hard Fault)

Posted by petegorba on December 15, 2015

Hi there

After changing only a little in my Code, the Application always ends up in the DummyHandler(); the error occurs after that code: if (xSemaphoreTakeFromISR(uartirq, portMAX_Delay)) (selfwirtten code) ldr r0, [r6] movs r1, #0 mov.w r2, #4294967295 blx r5 cmp ro, #0 beq #250

if(prvISQueueEmpty(pxQueue) != pdFALSE) (out of the FreeRTOS/queue.c) cmp.w r8, #0 bne 42

from here it jumps into the Dummy Handler.

Unfortunately i have no clue what this error is related to? Could there be a memory fault?

Thanks in advance for any help.

Programm ends up in Dummy Handler (Hard Fault)

Posted by rtel on December 15, 2015

When you say the code is self written do you mean you wrote a function that tries to block an ISR to wait for a semaphore? If so then that is not a valid thing to do - interrupts are under the control of the hardware, not the FreeRTOS scheduler. Otherwise you are just misusing the second parameter as it is not a block time. Please refer to the API documentation online.

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