nRF52 error during DFU process

[Mehdi]

Hi, 

I'm developing an nRF52 application based on SDK14 and S132 that require the DFU service.

The DFU is not performed using the nRF toolbox application on both of android and iOS with a different error message.

I got one of the error messages below: 

• Enabling Indication failed : Under iOS_V10.3.2.
• DFU device not bonded   : Under Android_V6.0.1.

When I tested with the DFU_Buttonless example from SDK14 the DFU performed correctly under Android.

Best Regards,

Mehdi.

[Einar Thorsrud]

Hi Mehdi,

This sounds like normal behaviour. The signature is not checked until the device enters the bootloader (no part of the DFU image is transferred while the device is in application mode). This is OK, as the purpose of the signing is to prevent the device from being programmed with a un-authorized firmware image.

If you want to prevent the device from entering bootloader mode, you should instead require security for writing to the DFU characteristic, triggering DFU mode. This is essentially a completely different problem, which has no relationship with the signature verification of the DFU image.

Best regards,

Einar