Hello,
I am using the custom board. There is 32MHz external oscillator. So, I implemented like below source code for clock control.
NRF_CLOCK->LFCLKSRC = (CLOCK_HFCLKSTAT_SRC_Xtal << CLOCK_HFCLKSTAT_SRC_Pos);
NRF_CLOCK->EVENTS_HFCLKSTARTED = 0;
NRF_CLOCK->TASKS_HFCLKSTART = 1;
NRF_CLOCK->XTALFREQ = CLOCK_XTALFREQ_XTALFREQ_32MHz;
But, I think that I need NRF_CLOCK->HFCLKSRC for external oscillator. In your nrf51 series reference manual, HFCLKSRC is referred. But, there is not any source code for HFCLKSRC in nrf51.h and there is not any register information for HFCLKSRC in reference manual.
Could you let me know the guide for it?
Thanks.