connecting nrf52840dk to nrf52840dongle uart examples

Hi,

It looks like the devices bonded before, but you deleted the bonding information (perhaps did a full flash erase?) one one of the devices? If so, the fix is to delete the bond on the other device as well so that they can pair.

Greetings Einar,

Thank you for your reply.

Pardon my ignorance, but how does one go about deleting a bond?

Thank you 

Hi,

To do it programatically you need to call bt_unpair(). But if the issue here is just something that happened when testing, for instance  because you flashed both peers with the respective firmware and then reased and re-flashed one of them, a simple fix would be to erase and reprogram both devices. If you do, erasing will also remove any bonding data and they can pair again.

Edit: If this is indeed the issue, you can also change the configuration to allow repairing by adding CONFIG_BT_SMP_ALLOW_UNAUTH_OVERWRITE=y to your prj.conf.

Greetings Einar,

I'm not sure if this is a bonding issue.

I added CONFIG_BT_SMP_ALLOW_UNAUTH_OVERWRITE=y as the last line under the "ENABLE BONDING" group in the prj.conf file in both central_uart and peripheral_uart samples, Reloaded thru Segger for Nordic V5.60 with clean build directory box checked, recompiled and re-flashed both binaries to their respective boards. I still get the exact same output in the debug terminal.  

Any alternative theories?

Thank you

Hi,

I see, there is another issue then. If I test with unmodified examples from 1.9.1 with a DK as central and dongle as peripheral, I get this log, as expected:

00> [00:00:00.011,566] <inf> fs_nvs: 8 Sectors of 4096 bytes
00> [00:00:00.011,596] <inf> fs_nvs: alloc wra: 0, fe8
00> [00:00:00.011,596] <inf> fs_nvs: data wra: 0, 0
00> [00:00:00.011,749] <inf> sdc_hci_driver: SoftDevice Controller build revision: 
00>                                          0e e7 c5 66 67 18 3c ac  b3 d2 cc 81 a3 dc f1 c0 |...fg.<. ........
00>                                          c0 36 02 22                                      |.6."             
00> [00:00:00.016,784] <inf> bt_hci_core: No ID address. App must call settings_load()
00> [00:00:00.016,784] <inf> central_uart: Bluetooth initialized
00> [00:00:00.018,890] <inf> central_uart: Scan module initialized
00> [00:00:00.018,920] <inf> central_uart: NUS Client module initialized
00> [00:00:00.029,571] <inf> central_uart: Scanning successfully started
00> [00:00:15.718,414] <inf> central_uart: Filters matched. Address: C6:A3:38:69:C3:45 (random) connectable: 0
00> [00:00:16.038,696] <inf> central_uart: Connected: C6:A3:38:69:C3:45 (random)
00> [00:00:16.139,862] <inf> central_uart: MTU exchange done
00> [00:00:17.647,277] <inf> central_uart: Pairing completed: C6:A3:38:69:C3:45 (random), bonded: 1
00> [00:00:17.647,552] <inf> central_uart: Security changed: C6:A3:38:69:C3:45 (random) level 2
00> [00:00:18.339,721] <inf> central_uart: Service discovery completed

You get error 9, which is BT_SECURITY_ERR_UNSPECIFIED. I do not immediately have any other theories. Do you by any chance have two DKs, so that you can easily get logs from the peripheral side and debug that as well? Or try with the peripheral on the DK and central on the dongle and share the log from the peripheral?