User App fails DFU at 10% completion

[Kevin s]

I'm having issues with my application implementing DFU. I added the DFU service in my application and can get into the bootloader. I have added my own key to the bootloader and have tested the bootloader out on an SDK52 dev board with the buttonless DFU application (modified according to all the comments in the forum). That works just fine.

SDK 12.1, SD 132 V 3.0

When I use my application and enter the bootloader, when I try to execute the DFU it stops at about 3 seconds into the process (or about 12% uploaded when I'm installing the HRM application as a test). I have a wireshark file of the transfer; I could not get the nrf logger to work with the nrfToolbox.

Apple_DFU_Fail.pcapng

Another bit of information; if I load just the bootloader and Softdevice, I can load my app when the dev Board powers up into the bootloader without any issues.

[Kevin s]

My Hardware was somehow interfering with the DFU....the person who made it put some foam insulation over the Nordic nRF52 IC. Once removed, everything works.

[Hung Bui]

Hi Kevin, it's pretty strange that the foam insulation can cause wrong behaviour to the chip. The only affect I can think of is if it's electrical conductive and cause short circuit, or it block the radio signal.

Heat could be a reason, but I don't think it can get above +85oC.