topic S32K144 RTC use external crystal 32.768KHZ inaccuracy in S32K

S32K144 RTC use external crystal 32.768KHZ inaccuracy

建宽高 — Wed, 19 Sep 2018 06:43:57 GMT

I use the following configuration

first , i config rtc

second ,i config clk_in pin

third ,i config clk

it is my code

/* Initialize RTC instance
* - See RTC configuration component for options
*/
RTC_DRV_Init(RTCTIMER1, &rtcTimer1_Config0);
/* Set the time and date */
RTC_DRV_SetTimeDate(RTCTIMER1, &rtcTimer1_StartTime0);

/* Start the RTC counter */
RTC_DRV_StartCounter(RTCTIMER1);

RTC_DRV_GetCurrentTimeDate(RTCTIMER1, &currentTime);

but i read inaccuracy time,it run fast.....

Re: S32K144 RTC use external crystal 32.768KHZ inaccuracy

danielmartynek — Wed, 19 Sep 2018 09:04:17 GMT

Hi,

The LPOCLKS[RTCCLKSEL] register is reset only on POR or LVD.

Can you power cycle the MCU?

Thanks,

Daniel

Re: S32K144 RTC use external crystal 32.768KHZ inaccuracy

建宽高 — Thu, 20 Sep 2018 06:26:20 GMT

yes, i can power cycle the mcu, Can you check my configuration is right?

Re: S32K144 RTC use external crystal 32.768KHZ inaccuracy

danielmartynek — Thu, 20 Sep 2018 07:31:54 GMT

Hi,

If it still doesn't work, please measure RTC CLKOUT.

What frequency do you get?

I don't see any problem in the configuration.

Regards,

Daniel