PCA21125 RTC Issue

[AshBirari]

Hello NXP,

I am bit confused about POR and RESET feature of PCA21125 rtc chip, what is difference between them?
Also How can we disable/clear POR bit of CONTROL1 register and RF bit of CONTROL2 register ?
I am trying to read time parameters of RTC but getting same data each time I flash the code. What should I do to get incrementing/ changing data for time parameters?

[TomasVaverka]

Hello Ashwini,

The POR ensures that the RTC initializes itself properly when power is applied. In other words, it ensures a controlled startup of the RTC.

As for the internal reset circuit, please refer to chapter 8.10 of the datasheet.

About the issue of getting the same data each time you read the time and date registers, there could be a few reasons:

- Ensure that the RTC clock is running. If the clock is not enabled, the time will not increment. Check the CONTROL1 register and make sure the clock is enabled.

- Make sure you are initializing the RTC properly, including setting the correct time and date initially.

- Ensure that you are reading the time and date registers correctly. 

Best regards,

Tomas