32.768khz crystal (LFXO)

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  • Hello,

    It appears Puck.JS does not have on board LFXO, If I connect one 32khz crystal to pins do I need to change settings somewhere?

    How about nRF52DK? It already has a LFXO. What settings I need to change to start saving power even if it is not much difference between RC XO (<5uA).

    Thanks

    https://devzone.nordicsemi.com/f/nordic-­q-a/14214/how-much-current-consumption-w­hen-we-use-internal-32k-rc

  • Hi,

    You're right, there's no external oscillator. The Softdevice actually does a pretty good job of calibrating its RC oscillator. Pin D0 is used for the button, so I don't believe you could add an RC oscillator to the Puck itself.

    On the DK it's not enabled either. You could recompile with this changed: https://github.com/espruino/Espruino/blo­b/master/targets/nrf5x/bluetooth.c#L1838­

    But it's been left out because I wan't able to find a way of checking if the LSE is there, and if it doesn't work when you upload the image then it's particularly frustrating.

  • Thank you very much Gordon for great products as well as a great support. I will do my part to support the Espruino by buying even more official hardware.
    :-)

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32.768khz crystal (LFXO)

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