Question
VREFINT magically turns on, MCU does not know about it
Posted on March 27, 2015 at 17:23
It would seem VREFINT magically turns on after coming out of sleep/stop even though it is not being used on the STM32L053 (nucleo board). It turns off for the first sleep/stop, then it wont turn off again. The MCU does not even seem to know about it.
The code is a minimal repro of the issue. It is based on the tamper timestamp example. For the first stop, I get ~7.6uA. Subsequently, it uses ~9.1uA. If one comments out line 45 (HAL_PWREx_EnableUltraLowPower()), usage is ~9.1uA for both. I have the code on Github too:https://gist.github.com/leppie/f3a5a64b2cc1f3622545
/*
stm32l0xx_hal_conf.h
#define HAL_MODULE_ENABLED
#define HAL_DMA_MODULE_ENABLED
#define HAL_FLASH_MODULE_ENABLED
#define HAL_GPIO_MODULE_ENABLED
#define HAL_PWR_MODULE_ENABLED
#define HAL_RCC_MODULE_ENABLED
#define HAL_RTC_MODULE_ENABLED
#define HAL_SPI_MODULE_ENABLED
#define HAL_CORTEX_MODULE_ENABLED
*/
#include ''stm32l0xx_hal.h''
#include ''stm32l0xx_nucleo.h''
#define RTC_ASYNCH_PREDIV 0x07
#define RTC_SYNCH_PREDIV 0x0FFF
RTC_HandleTypeDef RtcHandle;
static
void
SystemClock_Config(
void
);
static
void
RTC_TimeStampConfig(
void
);
int
main(
void
)
{
HAL_Init();
SystemClock_Config();
HAL_SuspendTick();
RtcHandle.Instance = RTC;
RtcHandle.Init.HourFormat = RTC_HOURFORMAT_12;
RtcHandle.Init.AsynchPrediv = RTC_ASYNCH_PREDIV;
RtcHandle.Init.SynchPrediv = RTC_SYNCH_PREDIV;
RtcHandle.Init.OutPut = RTC_OUTPUT_DISABLE;
RtcHandle.Init.OutPutPolarity = RTC_OUTPUT_POLARITY_HIGH;
RtcHandle.Init.OutPutType = RTC_OUTPUT_TYPE_OPENDRAIN;
if
(HAL_RTC_Init(&RtcHandle) != HAL_OK)
while
(1);
RTC_TimeStampConfig();
// this disables VREFINT in sleep/stop
// comment out to see the issue/difference
HAL_PWREx_EnableUltraLowPower();
while
(1)
{
// happens in sleep too
HAL_PWR_EnterSTOPMode(PWR_LOWPOWERREGULATOR_ON, PWR_SLEEPENTRY_WFI);
}
}
static
void
SystemClock_Config(
void
)
{
RCC_ClkInitTypeDef RCC_ClkInitStruct;
RCC_OscInitTypeDef RCC_OscInitStruct;
__PWR_CLK_ENABLE();
__HAL_PWR_VOLTAGESCALING_CONFIG(PWR_REGULATOR_VOLTAGE_SCALE2);
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_MSI;
RCC_OscInitStruct.MSIState = RCC_MSI_ON;
RCC_OscInitStruct.MSIClockRange = RCC_MSIRANGE_5;
RCC_OscInitStruct.MSICalibrationValue = 0x00;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
if
(HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
while
(1);
RCC_ClkInitStruct.ClockType = (RCC_CLOCKTYPE_SYSCLK | RCC_CLOCKTYPE_HCLK | RCC_CLOCKTYPE_PCLK1 | RCC_CLOCKTYPE_PCLK2);
RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_MSI;
RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;
if
(HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0) != HAL_OK)
while
(1);
}
static
void
RTC_TimeStampConfig(
void
)
{
RTC_DateTypeDef sdatestructure;
RTC_TimeTypeDef stimestructure;
RTC_TamperTypeDef stamperstructure;
stamperstructure.Filter = RTC_TAMPERFILTER_DISABLE;
stamperstructure.Tamper = RTC_TAMPER_2;
stamperstructure.Trigger = RTC_TAMPERTRIGGER_RISINGEDGE;
stamperstructure.SamplingFrequency = RTC_TAMPERSAMPLINGFREQ_RTCCLK_DIV256;
stamperstructure.PrechargeDuration = RTC_TAMPERPRECHARGEDURATION_1RTCCLK ;
stamperstructure.TamperPullUp = RTC_TAMPER_PULLUP_DISABLE;
stamperstructure.TimeStampOnTamperDetection = RTC_TIMESTAMPONTAMPERDETECTION_ENABLE;
HAL_RTCEx_SetTamper(&RtcHandle, &stamperstructure);
HAL_RTCEx_SetTimeStamp_IT(&RtcHandle, RTC_TIMESTAMPEDGE_RISING, RTC_TIMESTAMPPIN_PC13);
__HAL_RTC_TIMESTAMP_CLEAR_FLAG(&RtcHandle,RTC_FLAG_TSF);
sdatestructure.Year = 0x14;
sdatestructure.Month = RTC_MONTH_APRIL;
sdatestructure.Date = 0x14;
sdatestructure.WeekDay = RTC_WEEKDAY_MONDAY;
if
(HAL_RTC_SetDate(&RtcHandle,&sdatestructure,FORMAT_BCD) != HAL_OK)
while
(1);
stimestructure.Hours = 0x08;
stimestructure.Minutes = 0x10;
stimestructure.Seconds = 0x00;
stimestructure.TimeFormat = RTC_HOURFORMAT12_AM;
stimestructure.DayLightSaving = RTC_DAYLIGHTSAVING_NONE ;
stimestructure.StoreOperation = RTC_STOREOPERATION_RESET;
if
(HAL_RTC_SetTime(&RtcHandle,&stimestructure,FORMAT_BCD) != HAL_OK)
while
(1);
}
void
HAL_RTCEx_TimeStampEventCallback(RTC_HandleTypeDef *hrtc)
{
RTC_DateTypeDef sTimeStampDateget;
RTC_TimeTypeDef sTimeStampget;
__HAL_RTC_TAMPER_CLEAR_FLAG(hrtc,RTC_FLAG_TAMP2F);
HAL_RTCEx_GetTimeStamp(&RtcHandle, &sTimeStampget, &sTimeStampDateget, FORMAT_BIN);
}
void
HAL_RTC_MspInit(RTC_HandleTypeDef *hrtc __attribute((unused)))
{
RCC_OscInitTypeDef RCC_OscInitStruct;
RCC_PeriphCLKInitTypeDef PeriphClkInitStruct;
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_LSI | RCC_OSCILLATORTYPE_LSE;
RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;
RCC_OscInitStruct.LSEState = RCC_LSE_ON;
RCC_OscInitStruct.LSIState = RCC_LSI_OFF;
if
(HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
while
(1);
PeriphClkInitStruct.PeriphClockSelection = RCC_PERIPHCLK_RTC;
PeriphClkInitStruct.RTCClockSelection = RCC_RTCCLKSOURCE_LSE;
if
(HAL_RCCEx_PeriphCLKConfig(&PeriphClkInitStruct) != HAL_OK)
while
(1);
__HAL_RCC_RTC_ENABLE();
HAL_NVIC_SetPriority(RTC_IRQn, 0x0, 0);
HAL_NVIC_EnableIRQ(RTC_IRQn);
}
void
RTC_IRQHandler(
void
)
{
HAL_RTCEx_TamperTimeStampIRQHandler(&RtcHandle);
}