Hi,
I'm evaluating the nRF52840 using the DK. I find that the hfxtal in the 52840DK is GSX-223, which is not included in the data sheets characterization of HFXTAL ramp-up time.
My question is, I'm having problem when enabling the HFXTAL then going directly ramping up the radio.
// Enable the HFCLK NRF_CLOCK->EVENTS_HFCLKSTARTED = 0; NRF_CLOCK->TASKS_HFCLKSTART = 0x00000001; while(NRF_CLOCK->EVENTS_HFCLKSTARTED == 0); // Enable the Radio NRF_RADIO->EVENTS_READY = 0; NRF_RADIO->TASKS_TXEN = 1; while (NRF_RADIO->EVENTS_READY == 0);
as of the moment, what i'm doing is arm the RTC clock to fire 250us before enabling the HFCLK. I read somewhere that the BLE softdevice disables the HFCLK whenever the radio is not needed. I'm basically doing the same thing. Am I missing something?