Clock frequency, HW clock & RTOS tick time

[hiteshk014]

Hi Team,

We are using Nordic connect SDK nCS 1.9.1 & nrf52833

currently have not changed any clock frequency they're at default settings, we want to know what is the default clock settings in ncs, we're using VS Code studio, 

In nRF kconfig : System Clock's h/w timer frequency : 32768 

We have some mentioned queries mentioned below:

1. we want to know if we want to enhance the operating frequency, hardware clock & RTOS tick time what all modifications are to be done to enhance these parameters
2. In Prj.conf we tried these 2 settings -> CONFIG_SYS_CLOCK_TICKS_PER_SEC=983040 & CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC=100000for the mentioned settings in pt:2 will it have any major implications on SDK and it's features.

Thank you,

Regards,

Hitesh

[Einar Thorsrud]

Hi Hitesh,

I think there may be some misunderstandings here.

First of all, the CPU clock on the nRF52833 is always 64 MHz (using a 32 MHz reference). There are no configuration change you can do to influence this.

When it comes to the RTOS / Zephyr clock source, this is based on the RTC. The RTC runs of the 37.768 kHz oscillator , so the highest possible frequency you can use is 32768 Hz, which is what is used in the nRF Connect SDK. Setting CONFIG_SYS_CLOCK_HW_CYCLES_PER_SEC=100000 would simply not work. Also, using a lower value serves no practical purpose (you could use the RTC prescaler to et a lower frequency and adjust the configuration for that, but you would not gain anything by doing so).