Posted on October 03, 2017 at 13:06 Thank you
Turvey.Clive.002
for the suggestions.
I have gotten a little bit deeper and realized that the device is actually not going to sleep, and this happens sometimes every couple of minutes, or could be a couple of days. If the HAL_RCC_OscConfig() is calledwhen the device is awake then it fails and goes to the Error_Handler();. Of course, it shouldn't be called when the device is awake, but this would happen if the device fails to go to sleep.
I have the following function to go to sleep:
void enterStopMode(void){
if (HAL_RTCEx_SetWakeUpTimer_IT(&hrtc, 9, RTC_WAKEUPCLOCK_CK_SPRE_16BITS) != HAL_OK) {
TRACE_DBG_H('HAL ERROR -> HAL_RTCEx_SetWakeUpTimer_IT\n');
}
HAL_CRC_DeInit(&hcrc);
HAL_I2C_DeInit(&hi2c1);
HAL_I2C_DeInit(&hi2c2);
HAL_I2C_DeInit(&hi2c3);
isSleep=true;
TRACE_DBG_H('STOP\n');
HAL_UART_DeInit(&hlpuart1);
__HAL_PWR_CLEAR_FLAG(PWR_FLAG_WU);
__HAL_RCC_WAKEUPSTOP_CLK_CONFIG(RCC_STOP_WAKEUPCLOCK_MSI);
HAL_PWR_EnterSTOPMode(PWR_LOWPOWERREGULATOR_ON, PWR_STOPENTRY_WFI);
}
Sometimes this function doesn't go to sleep at all and code continues execution, where the HAL_RCC_OscConfig() is called and it fails as expected.
I noticed that in the Reference Manual (
http://www.st.com/content/ccc/resource/technical/document/reference_manual/2f/b9/c6/34/28/29/42/d2/DM000957pdf/files/DM000957pdf/jcr:content/translations/en.DM000957pdf
) page 161, Table 37, it says:
Note: To enter the Stop mode, all EXTI Line pending bits (in Section 5.6: EXTI pending register (EXTI_PR)), all peripherals interrupt pending bits, the RTC Alarm (Alarm A and Alarm B), RTC wakeup, RTC tamper, and RTC time-stamp flags, must be reset. Otherwise, the Stop mode entry procedure is ignored and program execution continues.
The only interrupt is the SysTick one. Could this be a race condition inside the
HAL_PWR_EnterSTOPMode that there's just an interrupt event before entering stop and makes it fail as per the note above?
void HAL_PWR_EnterSTOPMode(uint32_t Regulator, uint8_t STOPEntry)
{
uint32_t tmpreg = 0U;
/* Check the parameters */
assert_param(IS_PWR_REGULATOR(Regulator));
assert_param(IS_PWR_STOP_ENTRY(STOPEntry));
/* Select the regulator state in Stop mode ---------------------------------*/
tmpreg = PWR->CR;
/* Clear PDDS and LPDS bits */
CLEAR_BIT(tmpreg, (PWR_CR_PDDS | PWR_CR_LPSDSR));
/* Set LPSDSR bit according to PWR_Regulator value */
SET_BIT(tmpreg, Regulator);
/* Store the new value */
PWR->CR = tmpreg;
/* Set SLEEPDEEP bit of Cortex System Control Register */
SET_BIT(SCB->SCR, SCB_SCR_SLEEPDEEP_Msk);
/* Select Stop mode entry --------------------------------------------------*/
if(STOPEntry == PWR_STOPENTRY_WFI)
{
/* Request Wait For Interrupt */
__WFI();
}
else
{
/* Request Wait For Event */
__SEV();
__WFE();
__WFE();
}
/* Reset SLEEPDEEP bit of Cortex System Control Register */
CLEAR_BIT(SCB->SCR, SCB_SCR_SLEEPDEEP_Msk);
}
I'm not entirely sure if this could be the case. Any opinions?
Thanks all for your input.
Andrés
