MikroElektronika Forum

Posted: **25 Jun 2018 11:37**

Hi,

I have the RTC oscillator ticking over. So the RTC_start, RTC_Read, RTC_Write and RTC_Stop seem to be working.
It seems to be adding about 36 counts per second. Is this correct? This seems to be a bit of a strange value. How do you set a divisor for this?

Ultimately, what I would like to do is have a RTC interrupt that happens every second.

I have the RTC interrupt vector (void RTC_ISR() iv IVT_RTC_IRQ ics ICS_AUTO ) pointing to my RTC Time updating code but basically the system just locks up when I enable the interrupt
Using RTC_IEN_bit = 1 ;
RTC_CCR looks like 0x00 00 00 05.

Do I need to do something at the end of the interrupt ie clear a flag etc?

Thanks,
Neil.

Note tByte = unsigned char ;

Code: Select all

tByte rtc_start(void)
{
//    RTC->RTC_CCR |= MASK_RTC_CCR_EN;
    RTC_EN_bit = 1 ;
    return 0;
}


tByte rtc_stop(void)
{
//    RTC->RTC_CCR &= ~MASK_RTC_CCR_EN;
    RTC_EN_bit = 0 ;
    return 0;
}


tByte rtc_write(unsigned long val)
{
//    RTC->RTC_CLR = val;
    RTC_CLR = val;
    return 0;
}

tByte rtc_read(unsigned long *val)
{
//    *val = RTC->RTC_CCVR;
    *val = RTC_CCVR;
    return 0;
}


tByte rtc_init(rtc_wrap_t wrap)
{
    tByte iRet = 0;
    if (wrap > rtc_wrap_enabled)
    {
        iRet = -1;
    }

    if (iRet == 0)
    {
        rtc_write(0UL);

        switch(wrap)
        {
            case rtc_wrap_disabled: RTC_CCR |= RTC_WEN; break ;
            case rtc_wrap_enabled: RTC_CCR &= ~RTC_WEN; break ;
            default: break;
        }
    }

    RTC_IEN_bit = 1 ;
    return iRet;
}


void RTC_ISR() iv IVT_RTC_IRQ ics ICS_AUTO {
  tbyte a ;
  if (++RTClock.second==60)        //keep track of time, date, month, and year
  {
    RTClock.second=0;
    if (++RTClock.minute==60)
    {
      RTClock.minute=0;
      if (++RTClock.hour==24)
      {
        RTClock.hour=0;
        if (++RTClock.dow==7) RTClock.dow= SUN ;
        if (++RTClock.date==32)
        {

Etc etc

Posted: **28 Jun 2018 08:12**

Hi,
Yes, you need to clear the interrupt flag or you won't be able to enter that interrupt routine again.
You can check out this link, its an Interrupt Example for FT900x:
http://download.mikroe.com/documents/co ... rrupts.htm

If you need additional help regarding this, please post the zipped project so we could review it,.

Kind regards,
Petar

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