USB configuration conflicts with RTC_SetTime

[abelloni]

Posted on October 31, 2013 at 15:08

Hi everybody,

I'm using a STM32 L152CB microcontroller with external clock. Initially I used it without USB and the RTC_SetTime worked. Since I configured the USB, the function (RTC_SetTime) doesn't work and my RTC_TimeTypeDef struct is always to 0 for each parameters (day, month, etc..)

The micro's frequency is 16Mhz and the USB's clock is 48Mhz.

Have you suggestions?

Thanks!

#rtc #clock #usb

[chen]

Posted on November 01, 2013 at 12:16

Check your interrupt set up.

You mentioned the RTC is an external device - does it use IRQs??

The USB code relies heavily on IRQs, this may be interfering with the RTC code.

[Amel NASRI]

Posted on November 01, 2013 at 13:37

Is the function ''RTC_SetTime'' reached or the execution is stuck somewhere before?

Try to check this.

-Mayla-

[Tesla DeLorean]

Posted on November 01, 2013 at 14:45

I'm not entirely convinced there is a conflict between the RTC and USB.

Perhaps you can modify a VCP or MSC example to demonstrate this?

[kevin1078]

Posted on October 13, 2014 at 09:44

I also encountered this problem. It's stuck at RTC_EnterInitMode, waiting for RTC_ISR_INITF flag to be set. It succeeds before USB_Start, whereas fails after it.

[waclawek.jan]

Posted on October 13, 2014 at 10:13

When stuck, read out and post the content of RTC_ISR and RCC_CSR registers.

JW

[kevin1078]

Posted on October 13, 2014 at 10:32

In STM32L1XX_StdPeriph_Lib_V1.2.0,  there is no RCC_CSR, do you mean RCC_CR?

RCC_ISR: 0x00000234 (I also saw 0x0000003F before), RCC_CR: 0x00007340.

This stuck occurs right after the following code:

/*** Set interrupt mask ***/

  wInterrupt_Mask = CNTR_RESETM | CNTR_SUSPM | CNTR_WKUPM;

  _SetCNTR(wInterrupt_Mask);

Regards,

[waclawek.jan]

Posted on October 13, 2014 at 10:54

> In STM32L1XX_StdPeriph_Lib_V1.2.0,  there is no RCC_CSR, do you mean RCC_CR?

Who cares about the ''library''? See RM0038 ch.5.3.14.

>This stuck occurs right after the following code:

>

>/*** Set interrupt mask ***/

>  wInterrupt_Mask = CNTR_RESETM | CNTR_SUSPM | CNTR_WKUPM;

>  _SetCNTR(wInterrupt_Mask);

I have no idea, what is _SetCNTR(). Before, you told us that the stuck occurs at waiting for RTC_ISR.INITF. Show us the real code.

JW

[kevin1078]

Posted on October 13, 2014 at 11:10

Sorry, I typed RCC->CSR as RTC->CSR and got no result.

RTC->ISR: 0x00000234

RCC->CSR: 0x1E410300.

Code:

ErrorStatus RTC_EnterInitMode(void)

{

  __IO uint32_t initcounter = 0x00;

  ErrorStatus status = ERROR;

  uint32_t initstatus = 0x00;

     

  /* Check if the Initialization mode is set */

  if ((RTC->ISR & RTC_ISR_INITF) == (uint32_t)RESET)

  {

    /* Set the Initialization mode */

    RTC->ISR = (uint32_t)RTC_INIT_MASK;

    

    /* Wait till RTC is in INIT state and if Time out is reached exit */

    do

    {

      initstatus = RTC->ISR & RTC_ISR_INITF;

      initcounter++;  

    } while((initcounter != INITMODE_TIMEOUT) && (initstatus == 0x00));

    

    if ((RTC->ISR & RTC_ISR_INITF) != RESET)

    {

      status = SUCCESS;

    }

    else

    {

      status = ERROR;

    }        

  }

  else

  {

    status = SUCCESS;  

  }

    

  return (status);  

}

INITMODE_TIMEOUT = 0x2000

Thanks.

[kevin1078]

Posted on October 13, 2014 at 11:51

About _SetCNTR:

#define RegBase  (0x40005C00L)  /* USB_IP Peripheral Registers base address */

/* Control register */

#define CNTR    ((__IO unsigned *)(RegBase + 0x40))

#define _SetCNTR(wRegValue)  (*CNTR   = (uint16_t)wRegValue)

this function operates USB_CNTR register.

[kevin1078]

Posted on October 13, 2014 at 11:56

I can show all the project code if you want, but I'm afraid this will bother you since this will introduce lots of code.