nrf52840 Dongle pulsates but isnt detected by nrf connect for windows

[Stronk]

Hello,

Recently I purchased a nrf52840 Dongle to use it with nrfConnect for Windows.

I use nrfConnect 2.6.1. When I insert my Dongle in a USB port the LED starts pulsating.

In DeviceManager a device "Open DFU Bootloader" is added.

When opening nrfConnect and starting one of the apps (e.g. Programmer or Bluetooth Low Energy app) the Dongle is not recognized.

resetting the Dongle or pressing the button doesnt result in anything.

An other Dongle I have (nrf51 Dongle) works fine with nrfConnect

Any advise what I can do to get it going?

thanks!

[Simonr]

Hi

Have you tried the reset button (not the white one on top, small beige one by the Nordic logo). 

If this doesn't work, can you provide the dongle version and build. Preferably a picture of the white slip containing this info on the back of the dongle, so I can check for any errata.

Best regards,

Simon

[Stronk]

Hi Simon,

thanks for replying, see below (I hope it is readable)

I did try to reset, but the Dongle only restarts pulsing the LED

[Simonr]

Hi

First of all, go through this guide! If you can't get it to work you most likely have accidentaly erased UICR. To find out, please measure the voltage to be sure, if the measured voltage is 1.8V you have two options for recovery:

• Either use a debug probe that adapts the logic levels to the target device (for instance a J-Link PRO). Program firmware that configures REGOUT0 for 3 V.
• Or modify the dongle so that it can be supplied by an external supply and use the nRF52840 DK to program it.
  1. Adapt the dongle hardware as described under External regulated source in the nRF52840 Dongle documentation.
  2. Connect VDD from the nRF52840 DK to VDD OUT on the nRF52840 Dongle.
  3. Program via SWD as you have previously done (but remember to set REGOUT0 this time).

If the measured voltage is at 3V, please get back to me.

Best regards,

Simon

[Stronk]

Hi Simon,

Thanks for your quick response. Just to be sure it is not my laptop which is acting up, I put the Dongle in an other laptop. There it works as expected. Strange as my laptop has no issues with external USB drives and the NRF51 Dongle. Not sure what's the issue there but I'll dive into it.

So for now the issue is closed.

thanks.