Connect all the boards to the PC
Open a command window in that directory
.\pc-util\for_loop_batch_nRF52 this will program all the boards connected to the PC.
Take 4 boards off and connect to a USB hub connected to a Charger Determine the COM port of the remaining board by going to Device Manager>Ports (COM & LPT)
Open a command window in this directory.
<install directory for nrfutil>\pc-nrfutil\nrfutil dfu serial –pkg dfu_test.zip –p COMxx –b 115200 –fc –mesh this will program all the boards in the mesh with the blinky app. Wait until the upgrade occurs (approximately 15 minutes).
Here is what the command prompt should look like:
Repeated running of the download process is possible with the 0.8.7 version of the ble_mesh demo. However, it is necessary to create a new dfu_test.zip file. This test file must do two things, it must change performance, so that it can be proved that the download has actually occurred and it must have an application number higher than the last one downloaded. To accomplish this, the following step must be performed. In a command prompt, type the command:
.\pc-util\nrfutil.exe dfu genpkg –application ..\examples\BLE_Gateway \rbc_gateway_example_serial_nrf52832_xxAA.hex –company-id 0x00000059 –application-id 1 —application-version 3 –sd-req 0x0084 –mesh dfu_test.zip
Note the change in the application version from 1 to 2 and the change in the example used. This will accomplish both requirements stated above. The next step is to program that into the boards over the air. This is accomplished using the command
<install directory for nrfutil>\pc-nrfutil\nrfutil dfu serial –pkg dfu_test.zip –p COMxx –b 115200 –fc –mesh
This will program all the boards in the mesh with the blinky app (where COMxx is the COM port for the attached board). Upon completion, you will note that the blinking LEDs have been replaced with non-blinking LEDs. Further downloads can be accomplished by incrementing the application_version number and the executable itself.
Below is what you should see in the command window.