/* Start High Frequency Crystal Oscillator. 
Oscillator needs to be running for the radio to work. */
void clock_start_hfclk(bool wait)
/* Start High Frequency Crystal Oscillator. 
Oscillator needs to be running for the radio to work. */
void clock_start_hfclk(bool wait)
{
    periph_trigger_task(CLOCK_TASK_HFCLKSTART);
    if (wait) {
        while(!(CLOCK_HFCLKSTAT & CLOCK_HFCLKSTAT_STATE));
    }
}