Permanently set nRF52840 Dongle to advertising mode

[ble-at]

Hi, I have multiple nRF52840 Dongles and need to set one of them to permanently stay in advertising mode, even if a device disconnects.

If I use the nRF Connect tool to set the dongle to advertise, and then connect a different dongle to it and then disconnect the dongle again, nRF shows an error message ("Device disconnected") and turns off advertising. How can I make advertising stay on, no matter what happens (timeouts, disconnects,..)?

[Einar Thorsrud]

Hi,

nRF Connect for desktop Bluetooth does not have this feature, so it is not currently possible.

You can of course flash your own firmware to it instead, and do everything locally on the dongle instead of using nRF Connect for Desktop to control it. That way starting advertising again after disconnect is straight-forward (and default behavior of most examples). That may not work with your use case, though?

[ble-at]

Yes that would work as well, thank you! Is there example code available anywhere to get started with this?

[Einar Thorsrud]

I am not sure what your peripheral device is supposed to do, but ignoring that, you can for instance start of with the pca10059 (dongle) project for the Heart Rate Application. The example allready starts to advertise upon disconnect. You only need to modify it to never time out, by setting APP_ADV_DURATION to 0.