https://devzone.nordicsemi.com/f/nordic-q-a/68110/how-to-enter-the-interface-mcu-bootloader-mode-on-nrf9160dkHi team, How to enter the interface MCU bootloader mode on nRF9160DK. My DK can not find out the Jlink com virtual port. Thanks, Junen-USTelligent Community 13Tue, 10 Nov 2020 15:05:34 GMThttps://devzone.nordicsemi.com/thread/279321?ContentTypeID=1Tue, 10 Nov 2020 15:05:34 GMT137ad170-7792-4731-bb38-c0d22fbe4515:d1beaf57-5eb0-4653-975e-98df5f8d1ecdhelsing<p>Hi Jun,</p> <p>Sorry for the late reply.</p> <p>For your board to be in the Firmware development mode, please verify that SW6 is in the left position. Here is the description from the <a href="https://infocenter.nordicsemi.com/topic/ug_nrf91_dk/UG/nrf91_DK/if_mcu.html">nRF9160 DK User Guide</a>:</p> <blockquote> <h1>Firmware development mode</h1> </blockquote> <div> <blockquote> <p>The firmware development mode is the default with the IFMCU DISCONN switch (<span>SW6</span>) in the left position.</p> <p>The primary interface for programming and debugging the <span>nRF9160 DK</span> is the USB port (<span>J6</span>). The USB port is connected to an interface MCU which embeds a <a href="https://www.segger.com/products/debug-probes/j-link/models/j-link-ob/" rel="noopener noreferrer" target="_blank">SEGGER J-Link-OB</a> (On Board) debug probe.</p> <div><span><span><img alt=" " height="177" src="https://infocenter.nordicsemi.com/topic/ug_nrf91_dk/UG/nrf91_DK/images/nrf9160_dk_fw_dev_mode.svg" width="416" /></span></span></div> <div><span><span>Figure 1. </span><span>nRF9160 DK</span> firmware development mode</span></div> <div><span></span></div> </blockquote> </div> <p>(Note that this switch is named &#39;SW1&#39; on some board versions. However, I assume the position is still the same as in the image below.)</p> <p>Please let me know if you are still not able to find the JLINK.</p> <p></p> <p>Best regards,</p> <p>Håkon</p><div style="clear:both;"></div>