STM32F405 RTC counting more than 24h!

[Bruno Loureiro]

Posted on April 27, 2018 at 15:47

The RTC continues to count after 23:59:59, just changes the day at 39:59:59, what's the problem?

I use HAL Library.

RTC Output:

2018-04-06 weak5, 23:59:57

2018-04-06 weak5, 23:59:58

2018-04-06 weak5, 23:59:59

2018-04-06 weak5, 24:00:00

2018-04-06 weak5, 24:00:01

2018-04-06 weak5, 24:00:02

2018-04-06 weak5, 24:00:03

2018-04-06 weak5, 24:00:04

[john doe]

Posted on April 27, 2018 at 17:47

Looks like you have Binary Coded Decimal, when you want Bin.

there's bin2bcd and bcd2bin in the HAL RTC code file.  I forget if its in .h or .c, but they are there.

[Bruno Loureiro]

Posted on April 27, 2018 at 17:56

Hi,

I have already switched between Binary and BCD, but I always get the same bug.

Notice that I only have the problem in the Hour, and the day does not change either. 

I used this code in the past in STM32F407 and it worked fine.

[henry.dick]

Posted on April 27, 2018 at 19:10

Let's think through it logically.

It is definitely not a hardware problem: the same hardware has been used by countless others in countless applications flawlessly.

It is definitely not a software problem either you you seem to trust your code so much that you didn't even think posting it could help others help you. I'm 100 percent with you on that.

So here it is: we have a bug that is not hardware nor software related. Where else could the bug be hiding? In our minds?

[Bruno Loureiro]

Posted on April 27, 2018 at 19:44

At this moment I have no idea, you're right follow the code below.

 /* Infinite loop */

while (1){

   HAL_RTC_GetTime(&hrtc, &stimestructureget, FORMAT_BCD);

   if(stimestructureget.Seconds!=lastSecond)

   {

      HAL_GPIO_TogglePin(GPIOB,GPIO_PIN_9);

      HAL_RTC_GetDate(&hrtc, &sdatestructureget, FORMAT_BCD);

      leng=sprintf(printbuf,'20%02x-%02x-%02x weak%x, %02x:%02x:%02x\n\r',sdatestructureget.Year,       sdatestructureget.Month, sdatestructureget.Date,sdatestructureget.WeekDay,

      stimestructureget.Hours, stimestructureget.Minutes, stimestructureget.Seconds);

      HAL_UART_Transmit(&huart1,printbuf,leng,10000);

      lastSecond=stimestructureget.Seconds;

   }

}

/* RTC init function */

static void MX_RTC_Init(void)

{

   RTC_TimeTypeDef sTime;

   RTC_DateTypeDef sDate;

   /**Initialize RTC Only /

   hrtc.Instance = RTC;

   if(HAL_RTCEx_BKUPRead(&hrtc, RTC_BKP_DR0) != 0x32F2){

      hrtc.Init.HourFormat = RTC_HOURFORMAT_24;

      hrtc.Init.AsynchPrediv = 127;

      hrtc.Init.SynchPrediv = 255;

      hrtc.Init.OutPut = RTC_OUTPUT_DISABLE;

      hrtc.Init.OutPutPolarity = RTC_OUTPUT_POLARITY_HIGH;

      hrtc.Init.OutPutType = RTC_OUTPUT_TYPE_OPENDRAIN;

   if (HAL_RTC_Init(&hrtc) != HAL_OK)

   {

      _Error_Handler(__FILE__, __LINE__);

   }

   /**Initialize RTC and set the Time and Date

   */

   sTime.Hours = 0x0;

   sTime.Minutes = 0x0;

   sTime.Seconds = 0x0;

   sTime.DayLightSaving = RTC_DAYLIGHTSAVING_NONE;

   sTime.StoreOperation = RTC_STOREOPERATION_RESET;

   if (HAL_RTC_SetTime(&hrtc, &sTime, RTC_FORMAT_BCD) != HAL_OK)

   {

      _Error_Handler(__FILE__, __LINE__);

   }

   sDate.WeekDay = RTC_WEEKDAY_MONDAY;

   sDate.Month = RTC_MONTH_JANUARY;

   sDate.Date = 0x1;

   sDate.Year = 0x0;

   if (HAL_RTC_SetDate(&hrtc, &sDate, RTC_FORMAT_BCD) != HAL_OK)

   {

      _Error_Handler(__FILE__, __LINE__);

   }

   HAL_RTCEx_BKUPWrite(&hrtc,RTC_BKP_DR0,0x32F2);

   }

}

[Elivelton Santos]

Posted on April 27, 2018 at 21:50

Which STM32 exactly are you using?

Some STM32 only have RTC 'timer handle' that only counter 'the time', it doesn't count days (GetDate is emulated by software).

[Bruno Loureiro]

Posted on April 27, 2018 at 21:59

Hi,

STM32F405RGT6 I think he has a calendar ... Am I right?

[Elivelton Santos]

Posted on April 28, 2018 at 03:42

You are right. I can't see nothing wrong.

[waclawek.jan]

Posted on April 27, 2018 at 22:44

Read out the RTC registers and check/post them.

I see that in your init code there's RTC_HOURFORMAT_24 mentioned, but the symptoms are similar to the AM/PM (12-hour) cycle.

JW

[Bruno Loureiro]

Posted on April 28, 2018 at 14:16

Hi, You gave me a good idea, I changed the initialization to hrtc.Init.HourFormat = RTC_HOURFORMAT_12;

And in this configuration works :o  .... but I preferred the format 24h, I will do some more tests and put here the results.

[Bruno Loureiro]

Posted on April 28, 2018 at 14:27

Thanks to everyone, the solution is to change the location of this line in RTC Init

if (HAL_RTCEx_BKUPRead (& hrtc, RTC_BKP_DR0)! = 0x32F2) {

maybe some bug um STMCubeMX32

see function 

/* RTC init function */

static void MX_RTC_Init(void)

{

RTC_TimeTypeDef sTime;

RTC_DateTypeDef sDate;

/**Initialize RTC Only

*/

hrtc.Instance = RTC;

hrtc.Init.HourFormat = RTC_HOURFORMAT_24;

hrtc.Init.AsynchPrediv = 127;

hrtc.Init.SynchPrediv = 255;

hrtc.Init.OutPut = RTC_OUTPUT_DISABLE;

hrtc.Init.OutPutPolarity = RTC_OUTPUT_POLARITY_HIGH;

hrtc.Init.OutPutType = RTC_OUTPUT_TYPE_OPENDRAIN;

if (HAL_RTC_Init(&hrtc) != HAL_OK)

{

_Error_Handler(__FILE__, __LINE__);

}

/**Initialize RTC and set the Time and Date

*/

if(HAL_RTCEx_BKUPRead(&hrtc, RTC_BKP_DR0) != 0x32F2){

sTime.Hours = 0x0;

sTime.Minutes = 0x0;

sTime.Seconds = 0x0;

sTime.DayLightSaving = RTC_DAYLIGHTSAVING_NONE;

sTime.StoreOperation = RTC_STOREOPERATION_RESET;

if (HAL_RTC_SetTime(&hrtc, &sTime, RTC_FORMAT_BCD) != HAL_OK)

{

_Error_Handler(__FILE__, __LINE__);

}

sDate.WeekDay = RTC_WEEKDAY_MONDAY;

sDate.Month = RTC_MONTH_JANUARY;

sDate.Date = 0x1;

sDate.Year = 0x0;

if (HAL_RTC_SetDate(&hrtc, &sDate, RTC_FORMAT_BCD) != HAL_OK)

{

_Error_Handler(__FILE__, __LINE__);

}

HAL_RTCEx_BKUPWrite(&hrtc,RTC_BKP_DR0,0x32F2);

}

}

[henry.dick]

Posted on April 28, 2018 at 18:54

'

maybe some bug um STMCubeMX32'

understatement of the century,

that's the irony of a buggy library: it hurts the most people it is designed to help. If you were to simply write out your own code, you would have figured this out in a couple hours, not days.

[waclawek.jan]

Posted on April 29, 2018 at 10:39

the solution is to change the location of this line in RTC Init

if (HAL_RTCEx_BKUPRead (& hrtc, RTC_BKP_DR0)! = 0x32F2) {

Certainly not.

As long as the clock is running, i.e. battery is connected to VBAT, the RTC retains its settings and there's no need to reinitialize it upon reset. Contrary, by reinitialization you may disturb the clock (see numerous

https://community.st.com/0D50X00009XkgBWSAZ

in this very forum on subseconds being reset, thus losing up to 1 second upon each reset).

I am not going to comment on the quality of examples nor Cube. Read the RTC chapter in RM and write your own code.

JW

[Bruno Loureiro]

Posted on April 29, 2018 at 10:57

Hi, Thank you for the advice.