Does BLE run during MESH DFU?

[Shahin97]

Hello, 

It states in the documentation that during DFU MESH, the application is running and then switched over after the update is downloaded. My question is, if the application is using BLE-MESH to transmit data periodically, will that be stopped to prioritise the update as they both use BLE-MESH? 

[Edvin]

Hello,

The bootloader in the nRF5 SDK for Mesh is a background bootloader. This means that it is the application's job to transfer (receive, to be more specific) the image, and store it at a certain place in flash. During this time, the application will be running as normal, in parallel to receiving the DFU packets. So at this point in time, it will operate normally both with Mesh and BLE (if you are using "normal" Bluetooth Low Energy). 

When the transfer is complete, the bootloader needs to swap the old and new application. During this time, the application will not be operative, as it is the bootloader that controls the CPU. During this time the nRF will not receive or send any BLE or Mesh packets. However, this is only in the range of seconds. When it is done, it will start the new application.

Best regards,

Edvin

[Shahin97]

Fantastic explanation, Thank you