nRF52840 dongle connection loss with custom build

[Walther]

Hello all,

I tried to run the nRF52840 dongle and got some issues. I downloaded nRF Connect, SES and the nRF SDK and installed everything. I then tried the examples of the SDK (v15.3.0):

nRF5_SDK_15.3.0_59ac345\examples\ble_peripheral\ble_app_blinky\hex\ble_app_blinky_pca10059_s140.hex

I opened the programmer (v1.0.2) of the connect app (v2.6.2) on my Windows 7. I was able to write the hex file to the dongle, and tested it successfully with the iOS App. Everything worked fine. I could control the LED over the app and read out the value of the pushbutton. Then, I wanted to try the example built myself. I opened:

nRF5_SDK_15.3.0_59ac345\examples\ble_peripheral\ble_app_blinky\pca10059\s140\ses\ble_app_blinky_pca10059_s140.emProject

and built the solution. The build completed successfully. Then I tried to write the output hex file to the dongle. When I load it in the programmer, it looked quite different (just one green part in memory, no blue and orange one, as in the example hex), and when I try to write it, it says I have to choose a soft device. I select S140, as this was also the folders name. But then an error appears:

"The specified sdReq does not match the current SoftDevice. Please select a different value."

So I tried to manually add the soft device. I added the following hex file:

nRF5_SDK_15.3.0_59ac345\components\softdevice\s140\hex\s140_nrf52_6.1.1_softdevice.hex

Then, I am able to write it to the dongle. In the iOS app, I find the Dongle, and can connect to it. I also can control the LED on the dongle by sending the value to the service. However, when I push the button on the dongle, the connection is lost and the green LED is on again. I can connect again, control the LED, but as soon as I push the button, the dongle breaks again.

Do I have to program the dongle differently? Do I have to use another soft device? Is there something else I am missing?

Thank you very much for your help!

Walther

[Simonr]

Hi Walther

You need to incclude the SoftDevice .hex in addition to the application .hex. The pre-compiled .hex files in the example projects contains both of those in one file, which is why you are able to build the examples but not your custom code.

See this case for instructions on how to do so.

Best regards,

Simon

[Walther]

Hi Simon,

Thank you for your reply! I did this already, this was not my problem. As I wrote, in the program app I first selected the custom build hex file, then the S140 soft device hex file. Then I clicked on "write" and writing was successful. I could even connect to the dongle and control the LED. But as soon as I push the button on the dongle, it crashes. It seems to me that the dongle resets itself, as the connection is lost and the green LED for advertising is turned on again ~0.5seconds later.

With the pre-compiled example, I can push the button and the signal is transmitted to the iOS app.

Best Regards,

Walther