https://devzone.nordicsemi.com/f/nordic-q-a/66698/problem-nrf52840-not-deteced-j-link-driverI experimented with nRF52840 for 1 month. It was uploaded to the board well before, but suddenly I can&#39;t get the port. So after finding a lot of Q&amp;A, 1. Press button-4 + reset while power cycling. As soon as bootloader window pop-up download bin fileen-USTelligent Community 13Mon, 05 Oct 2020 10:46:15 GMThttps://devzone.nordicsemi.com/thread/272933?ContentTypeID=1Mon, 05 Oct 2020 10:46:15 GMT137ad170-7792-4731-bb38-c0d22fbe4515:11df9ba2-e011-4820-afcc-e119206635ffSigurd<p>Hi,</p> <p>Please go through the steps in the list in this post,&nbsp;<a href="https://devzone.nordicsemi.com/f/nordic-q-a/24592/my-nrf52-nrf51-dk-kit-doesn-t-work">https://devzone.nordicsemi.com/f/nordic-q-a/24592/my-nrf52-nrf51-dk-kit-doesn-t-work</a></p><div style="clear:both;"></div>