https://devzone.nordicsemi.com/f/nordic-q-a/56819/device-not-found-nrf5240-dkHi, I have received nRF52840 development kit recently and I am trying to work with Proximity demo application on my mobile phone. The problem is no device is shown on the nRF toolbox application. It seems that the nRF52840 Bluetooth is not recognizeden-USTelligent Community 13Wed, 22 Jan 2020 16:30:43 GMThttps://devzone.nordicsemi.com/thread/230420?ContentTypeID=1Wed, 22 Jan 2020 16:30:43 GMT137ad170-7792-4731-bb38-c0d22fbe4515:ffd0beba-f6ad-4b4a-aa6f-2d06ce026fb0WestCoastDaz<p>ghk,</p> <p>Interesting, which SES Project did you open and build?&nbsp; You need to ensure you choose the PCA10056 for the nRF52840-DK.</p> <p>As an alternative you can download nrfjprog and program the softdevice and prebuilt application onto the DK.</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/230268?ContentTypeID=1Wed, 22 Jan 2020 09:25:02 GMT137ad170-7792-4731-bb38-c0d22fbe4515:d6345d32-1dd1-4d8a-be36-bd060f8367a7ghk<p>I have used Segger Embedded Studio to build and run the example for heart rate. But when I open the android application &quot;nRF toolbox&quot; and then HRM, and then I push Connect button, no device is found.&nbsp;</p><div style="clear:both;"></div>https://devzone.nordicsemi.com/thread/230158?ContentTypeID=1Tue, 21 Jan 2020 18:37:35 GMT137ad170-7792-4731-bb38-c0d22fbe4515:b4bc581a-b7f6-4f48-b7b0-09ce4b4eea62WestCoastDaz<p><a href="https://devzone.nordicsemi.com/members/ghk">ghk</a></p> <p>How did you FLASH the application onto the DK?&nbsp; If you used nrfjprog then you need to FLASH the SoftDevice first and then the application.</p><div style="clear:both;"></div>