Questions about rtc example

[lyrics]

Hi, all

I'm using nRF52840, pca10056.

I have a question about the rtc example of peripheral.

I want to know the difference between 'nrf_drv_rtc_init' and 'nrf_drv_rtc_cc_set' exactly.

What I confusing : 

1. I changed config.prescaler value 4095 to 16380 to change the clock period to 0.5.

    But there is no change. What did I miss?

2. Is the role 'nrf_drv_rtc_cc_set' all that LED2 turns on after COMPARE_COUNTERIME seconds?

3. I also referred to nordic semiconductor RTC example.

...

   What does 'clears the interrupt request' mean in the first paragraph of the description and which part of the example code does it represent? 

BR,

lyrics

[Vidar Berg]

Hello,

1. The PRESCALER register is 12 bit, which means that 4095 is the largest prescaler setting you can use. Please see the "Resolution versus overflow and the PRESCALER" section of the PS for more examples of how you can calculate the frequency.

2. This function sets the CC[x] registers to use the Compare feature, and it controls the interval at which the NRF_DRV_RTC_INT_COMPAREx event is triggered ( 3 seconds by default)

3. Interrupts are cleared when the program exits your rtc_handler() function. This allows the RTC to trigger a new interrupt next time the NRF_DRV_RTC_INT_COMPARE0 or the NRF_DRV_RTC_INT_TICK event occurs.

Best regards,

Vidar