https://devzone.nordicsemi.com/f/nordic-q-a/45150/pca10040-v1-2-4-suitable-clock-accuracyHello All, I am currently working with two boards of PCA10040 One of them is v1.1.1 and the other one is v1.2.4 My code must connect with other nrf52 boards to exchange data with it when flashing the code in v1.1.1 the two devices are connecteden-USTelligent Community 13Thu, 21 Mar 2019 10:25:44 GMThttps://devzone.nordicsemi.com/thread/177538?ContentTypeID=1Thu, 21 Mar 2019 10:25:44 GMT137ad170-7792-4731-bb38-c0d22fbe4515:a595c33d-8b28-4636-80b6-8c134c450f29Einar Thorsrud<p>Hi,</p> <p>All nRF52832 DK versions have a 20 ppm 32.768 kHz LF crystal. It might be that there is a problem with your DK. You can check the accuracy of the LFCLK for instance by using a RTC to toggle a GPIO via PPI and connect it to a frequency counter.</p> <p>An alternative explanation could be if you have modified the example to use the internal RC oscillator instead? If so, this has a 500 ppm accuracy (instead of the specified 250 ppm due to erratum xxx). If you use a recent SDK you need to set the accuracy correctly when using the PPM. With older SDKs accuracy was always set high when using RC.</p><div style="clear:both;"></div>