52840 uart DFU with sdk16.0 bootloader problem

[William.wei]

I tested sdk16.0 with secure uart debug example, that DFU needs to enter bootloader twice(press button4 and reset twice), first time to update setting file, second time to update application.

 otherwise it lost app updating, stop at about 86% percent's, it puzzles me and customer for a long time, i don't know why? is it a bug?

thank you!

[Vidar Berg]

Hi,

You should only provide the application image when updating the app. The BL settings page is controlled updated by the bootloader as a part of the DFU process. What happens if you start with the app update?

[William.wei]

hi Berg, thanks,

it is ok to update application only, so do you mean the customer should not update the softdevice+bootloader+application at the same time? 

[Vidar Berg]

No, you should be able to update softdevice+bootloader+application at the same time. I thought you were attempting to update the Bootloader settings page through DFU, which is not possible. 

[William.wei]

Thank you Berg, with 40 seconds timeout in bootloader, it is ok to update  softdevice+bootloader+application now,