Hi,
We have a problem where we think that a memory alignment issue is causing
a hard fault, but can't work out why.
We are using ...
stm32f765.
Atollic 9.3.0 (for legacy purposes)
No operating system.
stlink v2 for debug.
The following code is what we label as bad. This code will run on the debugger,
but will not run from a power up reset.
Taken from P5003_stm32f7xx_it.c
/**
* @brief This function handles Pendable request for system service.
*/
void PendSV_Handler(void)
{
/* USER CODE BEGIN PendSV_IRQn 0 */
/* USER CODE END PendSV_IRQn 0 */
/* USER CODE BEGIN PendSV_IRQn 1 */
/* USER CODE END PendSV_IRQn 1 */
}
/**
* @brief This function handles System tick timer.
*/
#warning "SysTick_Handler before peripheral interrupt handlers == cold start fail"
#warning "SysTick_Handler before PendSV_Handler == cold start ok"
void SysTick_Handler(void)
{
HAL_IncTick();
}
The code below is labelled as good, as it runs on both the debugger and from a power
up reset. The only difference is that we have swapped the two handlers SysTick_Handler()
and PendSV_Handler() around.
#warning "SysTick_Handler before peripheral interrupt handlers == cold start fail"
#warning "SysTick_Handler before PendSV_Handler == cold start ok"
void SysTick_Handler(void)
{
HAL_IncTick();
}
/**
* @brief This function handles Pendable request for system service.
*/
void PendSV_Handler(void)
{
/* USER CODE BEGIN PendSV_IRQn 0 */
/* USER CODE END PendSV_IRQn 0 */
/* USER CODE BEGIN PendSV_IRQn 1 */
/* USER CODE END PendSV_IRQn 1 */
}
/**
* @brief This function handles System tick timer.
*/
The attached Stm32f765AlignmentProblem.Zip contains good and bad folders which
further contain the .map .elf .list .hex and the P5003_stm32f7xx_it.c file for
we think is causing the problem. We have so far determined that there is
an imprecise bus fault occrring, but don't know why swapping these two handlers causes
it to stop. Is it now being masked until we add more code to cause it to come back again?
Any help in understanding the problem would be greatly appreciated.
Note we have used -falign-functions gcc compiler options and this fixes the problem
with the bad code, but only because it has realigned it.
