Is the 32MHz crystal oscillator active when the nRF54L15 program begins execution?

[Kenta]

Hello.

This may be a basic question, but please let me know.
I am using nRF54L15-DK and nRF Connect SDK v3.0.2.

Is the 32MHz crystal running when the nRF54L15 program starts?

I've read the documentation, but it's difficult.
docs.nordicsemi.com/.../clock.html

I Use the peripheral_uart sample

int main(void){
    if(NRF_CLOCK->EVENTS_XOSTARTED == 1){
        printk("Clock started.\n");
    }else{
        printk("Clock not started.\n");

    }
}

I added this to the beginning of main and checked the program, and it displayed "Clock not started."

Does this mean that the 32MHz crystal is not running?

Best regards.

[Kazi Afroza Sultana]

Hello,

Crystal does not run automatically until it's called by any peripheral or Radio for high accuracy. 

By default, the system uses the internal oscillator (HFINT) to save power, and only switches to the external crystal when needed.

[Kenta]

Hello Kazi Afroza Sultana.

I just removed the 32MHz crystal from the board and checked it.

printk("Hello world.\n");
runs fine, and the Bluetooth application stops at MPSL initialization.

As you said, I was able to confirm the operation of the internal oscillator and the external crystal.

Thank you for your cooperation.

Best regards.