https://devzone.nordicsemi.com/f/nordic-q-a/22902/nrf51822-sniffer-firmware-upgrade-problemI want to use nRF51822 Bluefruit LE Friend device (blue board) as BLE Sniffer. My OS is Windows 7 64-bits. I installed ble-sniffer_win_1.0.1, v1.0: FTDI Driver Requirements (Blue Boards), etc (according the learn.adafruit.com/.../field-updates) . Whenen-USTelligent Community 13Tue, 20 Jun 2017 08:30:23 GMThttps://devzone.nordicsemi.com/thread/90062?ContentTypeID=1Tue, 20 Jun 2017 08:30:23 GMT137ad170-7792-4731-bb38-c0d22fbe4515:2ee54ffe-6de9-4966-babe-166ec3b96ea3J&#248;rgen Holmefjord<p>Hi,</p> <p>These are generally questions you should ask Adafruit, as this is their own hardware/firmware, only using Nordic chips, but I will try to give you some pointers.</p> <p>Did you see the big red warning in the <a href="https://learn.adafruit.com/introducing-the-adafruit-bluefruit-le-sniffer/python-api?view=all#select-the-sniffer-target">sniffer guide</a> telling you to ignore the firmware update message?</p> <p>I&#39;m not sure why you are not able to put your device into DFU mode, but from what I can see in <a href="https://github.com/adafruit/Adafruit_BluefruitLE_Firmware/issues/3">these comments</a>, and <a href="https://learn.adafruit.com/introducing-adafruit-ble-bluetooth-low-energy-friend/faq#faq-9">this FAQ</a>, it is not possible to switch from &quot;standard firmware&quot; to &quot;sniffer firmware&quot; OTA. You will need a SWD programmer to do this transition. Also note the warning that this is done at your own risk.</p> <p>Best regards,</p> <p>Jørgen</p><div style="clear:both;"></div>