I want to use a UART DFU Bootloader in 52840, I uploaded a app by nrfutil, If I want to enter the DFU mode again in the app, I should press button 1 and then press button 4, I want to know the mechanism?

[oplinux]

Hi guys:

  a. I use a uart dfu bootloader(loacation: SDK-location\nRF5_SDK_15.0.0_a53641a\nRF5_SDK_15.0.0_a53641a\examples\dfu\secure_bootloader\pca10056_uart) in 52840 soc.

  b.I flashed the bootloader and SoftDevice by nrfjprog firstly.(cmd: nrfjprog -f NRF52 --program boot.hex)

  c.Then, I upload app.zip package by nrfutil.(cmd: nrfutil  dfu serial -pkg test-dfu15.zip -p COM16 ), the app is SDK-location\nRF5_SDK_15.0.0_a53641a\nRF5_SDK_15.0.0_a53641a\examples\ble_peripheral\ble_app_uart.

  d. I found If I want to enter the bootloader again when Iam in app, I should press the DK-52840 board button 1 and then press button 4.

  Can you tell me the mechanism and the funtion of button 1 and button 4?

  Thanks.

    

[Einar Thorsrud]

Hi,

This is not expected. Have you been able to reproduce this? Can you explain in detail which difference you see with and without the bootloader? Generally speaking, the presence of a bootloader should not have any effect on the application.