DFU failed after GATT connected.

[Kenta Harada]

I met this issue on some Android devices. GATT connection is disconnected before before service discovery finished. The issue is reporeted in following link.

github.com/.../35

I'd like to know the workaround of this issue.

[Kenta Harada]

I tried to find the difference between nRF toolbox source code and ours. but I could not find the difference. nRF sniffer doesn't work well after device turned to bootloader mode. Do you have any other advice?

[Hung Bui]

What do you mean by "nRF sniffer doesn't work well after device turned to bootloader mode" ? If you have trouble because the device change the address, you simply test with just the bootloader and no application, then the device will always be in bootloader.

You do have issue doing DFU with nRFToolbox , but don't with NRFConnect correct ?

[Kenta Harada]

Thank you for your comment. I removed the pairing/bonding process from Android application an nRF52 FW. DFU finished successfully. But we need encryption, How should we do ? Use AES encryption without pairing, is that good idea ?

[Hung Bui]

@Kenta: By default the ble_app_hrm buttonless example in SDK v11 does support bond forwarding. Do you follow what implemented there to call the SVC call to send bond information to the noinit data area ? If no bonding is forwarded, the phone will terminate the connection because it can't re-encrypt with the device.

If you want simply to keep bonding on the application, but OK to have non-bonding for DFU, then you can change the address of DFU bootloader to something else (suggest to be +1 of original address) so that no bonding will be used when doing DFU.

[Kenta Harada]

Thank you for your comment. We don't currently use bond sharing feature. if that is the cause of this issue, we want to use it !

But Bjørn Spockeli said that SDK v11 doesn't support bond sharing which uses peer manager in following question.(We use peer manager, don't use bond manager.)

devzone.nordicsemi.com/.../

Are there any workaround ?