DFU for BLE beacon using NRF51822 with SDK 12.3

[michel21033]

I need to develop a beacon application with the OTA DFU capabilities (Buttonless). I have the NRF51-DK. 

As a starting point, I tried the bootloader example located in the \nRF5_SDK_12.3.0_d7731ad\examples\dfu directory to do a secure DFU( with button).  I followed the instructions up to step D found in this  Ble tutorial.

I am using the ble_app_beacon example with S130 soft device.

Once i do DFU, the dev kit stops advertising altogether. I am able to put the dev kit in to DFU mode again by pressing button 4 during power up. Why doesn't the dev kit advertise? 

I assume that after I do the dfu, the dev kit should act as a non-connectable beacon unless I put it in DFU mode by pressing button 4 at power up. Am I correct? 

[michel21033]

I have successfully tested the secure dfu with the use of the button. However I'm not able to get it working without the button. I compiled the experimental buttonless dfu template app and uploaded via secure dfu mentioned above. I am using the nrf connect android app and I am able to see the dk advertising as buttonless dfu template. How do I then put the device in boot loader mode.? The documentation says to write 0x01 ? Can someone point me in the right direction?

In my final application, in order to have buttonless dfu, should the beacon be in connectable mode?

Should I build the beacon app on top of the template?

What would be the advertised id? I am planning to make the beacon packet ibeacon compatible.

[Bjørn Kvaale]

As the documentation shows, you are correct that you should write 0x01 to the DFU control point characteristic. It should work with both nrf connect for mobile & nrf toolbox? Have you tried with nrf toolbox yet? I believe the beacon will need to be in connectable mode to be able to write the 0x01 to the DFU control point characteristic. The beacon app can be added just like in step C1 of the secure dfu blog post. You will not need to build the beacon app on top of the buttonless dfu bootloader template. 

As this link states: "the beacon is advertising with its Bluetoothdevice address without a Device Name". Hope that helps!