RTC DeInit problem in the example code

[fanziyu]

Hi,everyone! 

I found a problem when I referred to the example code. the codes "while(RTC->MOD)" will spend more than 1 second.I use the oscilloscope to observe in my project .Could you help me?

mcu:keazn8

example code:

void RTC_DeInit(void)

{

   Disable_Interrupt(RTC_IRQn);

   RTC->MOD = 0;

   while(RTC->MOD);

   if(RTC_GetFlag())

  {

      RTC_ClrFlags();

   }

  RTC->SC = 0;

  while(RTC->SC);

  SIM->SCGS &= ~SIM_SCGC_RTC_MASK;

}

My code:

void RTC_DeInit(void)
{
      Disable_Interrupt(RTC_IRQn);

      RTC_MOD = 0;
      while(RTC_MOD);      
      if(RTC_SC_RTIF_MASK == (RTC_SC & RTC_SC_RTIF_MASK))
      {
            RTC_SC |= RTC_SC_RTIF_MASK;
       }

      RTC_SC = 0; 
      while(RTC_SC);
      SIM_SCGC &= ~SIM_SCGC_RTC_MASK;
}

[mjbcswitzerland · Accepted solution]

Hi

A write to the RTC modulo register is latched until the RTC counter overflows

To avoid the code blocking you can use the RTC interrupt to inform you when it has completed this "parking" of the timer so that it is in its reset state again.

You might like to also try changing the clock source in RTC_SC after setting the module to 0 since it states that doing this will clear both the module and counter, which may then be instantaneous.

Regards

Mark

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