DFU over USB fails at 75% with application + Soft Device + bootloader

[mablabs]

Hi,

We've created a FW image targeting a PCA10056 which consists of our application FW, the example secure DFU bootloader over USB, and the softdevice. Everything works fine (we can interact with the application and receive expected data). Although we can jump to the bootloader on power up by pressing the appropriate button and even launch DFU, the transaction always seems to fail at 75% and we see that the USB to serial connection is disconnected. We have tried this on both Windows and Linux and see the same behavior. Our DFU package contains a bootloader, Soft Device, and application. We need to update the application and bootloader, and since we can't update only those two, we need to package the Soft Device as well.

Can you advise as to what could be the issue?

Thank you,

Mohammed

[mablabs]

Hi Vidar,

Thanks for getting back. I'm using nrfutil version 6.1.0 and SDK version 17.

Mohammed

[Vidar Berg]

Hi Mohammed,

OK, thanks for confirming that the SDK and nrfutil version is up to date. Could you please try to make an application-only update package and try to upload it after the first update has failed at 75%

Vidar

[mablabs]

Hi,

After the initial update fails at 75%, I can't enter the bootloader by holding down button 4. I need to reflash the USB bootloader + application + Soft Device and then jump to the bootloader. After that I can successfully program the application only.

Mohammed

[Vidar Berg]

That's interesting. So when you reflash the board again, are you flashing the new or the old bootloader?

[mablabs]

When I reflash the board again, I'm flashing the USB bootloader.

[mablabs]

Sorry hit "Reply" to soon. I'm reflashing the USB bootloader + application + soft device.