I would like to know the accuracy of the nrf51 timer.

[tadanohito]

I am a beginner in embedded systems.

I know that the minimum resolution of RTC is 1/32768, but what is the effective number of digits for this? For example, I used a counter to obtain "55100023" as the value of the time since the start of the program.

Divide this value by 32768 to get 1681.51925...is obtained. How many digits can this value be trusted?

[haakonsh]

It depends on the accuracy of the clock source. What is your clock source?

[tadanohito]

I don't know what it refers to, but the device used is nrf51. The SDK used is NCS1.6.0 and the count is obtained by "k_cycle_get_32()".

[haakonsh]

What is your kernel clock configuration?

[tadanohito]

I don't know what it is and where to look for it. Here is the "kernel.h" file that contains the functions I used.kernel.h

And this may be an off-the-wall answer, but in "system_nrf51.c", I set "#define __SYSTEM_CLOCK (32000000UL)".

[haakonsh]

You can use menuconfig to view your kernel configurations. 

Look for CONFIG_SYS_CLOCK_TICKS_PER_SEC, and clock sources and accuracies.