NRF DFU (Serial Transport)

[Dominic]

SDK v16.0 NRF52832

Hi 

We have been using the the NRF Bootloader for sometime, but we have encountered an issue where if the DFU (Serial) is interrupted (ie, USB cable is removed). On restart, the MCU enters DFU as predicted (the application image is removed) but then we cannot update with the same image again (xxx.zip). 

nrfutil reports:

"NordicSemiException: Did not receive checksum response from DFU target. If MSD is enabled on the target device, try to disable it ref." 

Looking the the verbose output from nrfutil, the last action is:

2020-08-26 01:07:48,953 SLIP: --> [3]
Traceback (most recent call last):
File "/home/ee//.local/bin/nrfutil", line 8, in <module>

The only way we can update again is if we regenerate the package again with nrfutil (ie, give it a new signature) 

My question is if this is intended behaviour? 

Thanks in advance! 

Dominic

[Vidar Berg]

Hi Dominic,

The only way we can update again is if we regenerate the package again with nrfutil (ie, give it a new signature) 

I'm not sure why it helps to re-generate the DFU package, does it always help?  And is the new package supposed to be identical, or is it generated with updated version numbers, etc in the init packet?

Have you tried to disable the MSD class as the warning suggested (Disabling MSD - remember power-cycle at the end)?

Best regards,

Vidar