https://devzone.nordicsemi.com/f/nordic-q-a/21832/problem-facing-on-pairing-the-bluetooth-in-nrf52dkHola community, I am using nrf52DK for the first time and am unable to connect it to my mobile phone using Bluetooth. The problem I am facing at the moment is, the device is not visible in the app i have downloaded from play store (nRF connect). I amen-USTelligent Community 13Fri, 05 May 2017 08:50:10 GMThttps://devzone.nordicsemi.com/thread/85745?ContentTypeID=1Fri, 05 May 2017 08:50:10 GMT137ad170-7792-4731-bb38-c0d22fbe4515:213b1265-a691-4c52-a0e4-12d914c2a659Sigurd<p>Hi,</p> <p>If the nRF52 is not visible in nRFConnect, the nRF52 is probably not advertising. When advertising LED1 on the DK should blink. Have you uploaded the SoftDevice? What SDK version are you using? If you are using SDK 13, you have to use SoftDevice S132 v.4.0.2 as seen in the compatibility matrix <a href="https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf52/dita/nrf52/compatibility_matrix/ic_rev_sdk_sd_comp_matrix.html?cp=2_0_1_2">here</a>. The SoftDevice is the Bluetooth low energy(BLE) protocol stack. You can find the SoftDevice in the folder:</p> <pre><code>SDK_FOLDER\components\softdevice\s132\hex </code></pre> <hr /> <p>There are two ways to flash the SoftDevice to the nRF52 DK.</p> <p><strong>Option 1 - nRFGO Studio</strong> :</p> <p>Download nRFGo Studio from the page linked to below</p> <p><a href="https://www.nordicsemi.com/eng/Products/2.4GHz-RF/nRFgo-Studio/">www.nordicsemi.com/.../</a></p> <p>Install, and then Open nRFGo Studio, select the Segger xxxxxxxxx device in the Device Manager, then select the Program SoftDevice tab, navigate to the \components\softdevice\s132\hex folder and select the s132_nrf52_4.0.2_softdevice.hex file(for SDK 13) and press program.</p> <p><strong>Option 2 - nrfjprog</strong>:</p> <p>Download nRF5x Command Line Tools</p> <p><a href="https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.tools/dita/tools/nrf5x_command_line_tools/nrf5x_installation.html?cp=5_1_1">infocenter.nordicsemi.com/.../nrf5x_installation.html</a></p> <p>Using the command line, you can flash the SoftDevice with the command</p> <pre><code>nrfjprog --family nrf52 --program s132_nrf52_4.0.2_softdevice.hex --verify </code></pre> <p>If you get an error stating that the flash is not erased, then you can erase the flash of the chip with the following command</p> <pre><code>nrfjprog --family nrf52 --eraseall </code></pre><div style="clear:both;"></div>