Linux-enabled BLE HID peripheral

[DX_HK]

I am trying to develop a BLE HID peripheral that can be used on Ubuntu 24.04.

When I try to connect the peripheral_hids_mouse example to a Linux machine, it immediately disconnects and becomes unusable.

Is there any sample code that has been confirmed to work with Linux machines?
Or is this a problem specific to my environment?

I am using nRF52840DK and NCS 3.0.2.

The host Linux machine is a Lenovo ThinkPad T14s. It works fine with other Logitech devices.

[Lorenzo Amicucci]

hi

yes, have you tried "nRF Desktop" application in nRF Connect SDK? 

Lorenzo

[Edvin]

Hello,

Does the log from the nRF say anything when it disconnects? Particularly, what is the "reason" parameter in the disconnected event? And does the log say anything about "security change"?

Best regards,

Edvin

[DX_HK]

Thank you for your response.
As you said, I tried nRF Desktop.
I found that it works without any problems.

On the other hand, nRF Desktop is an application-level implementation and is too complex as sample code.
Is there any simpler BLE sample code that has been verified to work?

[DX_HK]

*** Booting nRF Connect SDK v3.0.2-89ba1294ac9b ***
*** Using Zephyr OS v4.0.99-f791c49f492c ***
[00:00:00.024,871] <inf> main: Starting Bluetooth Peripheral HIDS mouse sample
[00:00:00.039,337] <inf> fs_nvs: 2 Sectors of 4096 bytes
[00:00:00.045,288] <inf> fs_nvs: alloc wra: 0, ef8
[00:00:00.050,720] <inf> fs_nvs: data wra: 0, 17c
[00:00:00.056,182] <inf> bt_sdc_hci_driver: SoftDevice Controller build revision: 
                                            89 9a 50 8a 95 01 9c 58  fc 39 d2 c1 10 04 ee 02 |..P....X .9......
                                            64 ce 25 be                                      |d.%.             
[00:00:00.089,599] <inf> bt_hci_core: HW Platform: Nordic Semiconductor (0x0002)
[00:00:00.097,747] <inf> bt_hci_core: HW Variant: nRF52x (0x0002)
[00:00:00.104,522] <inf> bt_hci_core: Firmware: Standard Bluetooth controller (0x00) Version 137.20634 Build 2617349514
[00:00:00.116,546] <inf> bt_hci_core: No ID address. App must call settings_load()
[00:00:00.124,847] <inf> main: Bluetooth initialized
[00:00:00.132,263] <inf> bt_hci_core: Identity: D7:27:30:94:0A:33 (random)
[00:00:00.139,892] <inf> bt_hci_core: HCI: version 6.0 (0x0e) revision 0x10f3, manufacturer 0x0059
[00:00:00.149,658] <inf> bt_hci_core: LMP: version 6.0 (0x0e) subver 0x10f3
[00:00:00.159,973] <inf> main: Direct advertising to 14:5A:FC:4B:71:00 (public) started
[00:00:01.440,277] <inf> main: Direct advertising to 14:5A:FC:4B:71:00 (public) timed out
[00:00:01.450,744] <inf> main: Regular advertising started
[00:00:20.254,913] <inf> bas: BAS Notifications enabled
[00:00:20.261,169] <inf> main: Connected 14:5A:FC:4B:71:00 (public)
[00:00:20.268,249] <inf> main: Conn details (post-connect): 14:5A:FC:4B:71:00 (public) role peripheral interval 36 latency 0 timeout 42 sec_level 1 key_size 0
[00:00:20.285,705] <inf> main: Regular advertising started
[00:00:20.870,758] <inf> main: Passkey for 14:5A:FC:4B:71:00 (public): 636211
[00:00:20.878,631] <inf> main: Press Button 1 to confirm, Button 2 to reject.
[00:00:21.590,209] <inf> main: Security failed: 14:5A:FC:4B:71:00 (public) level 1 err 9 
[00:00:21.599,365] <inf> main: Conn details (security cb): 14:5A:FC:4B:71:00 (public) role peripheral interval 36 latency 0 timeout 42 sec_level 1 key_size 0
[00:00:21.614,532] <inf> main: Pairing failed conn: 14:5A:FC:4B:71:00 (public), reason 9 
[00:00:21.623,596] <inf> main: Conn details (pairing failed): 14:5A:FC:4B:71:00 (public) role peripheral interval 36 latency 0 timeout 42 sec_level 1 key_size 0
[00:00:21.639,038] <inf> bas: BAS Notifications disabled
[00:00:21.645,294] <inf> main: Disconnected from 14:5A:FC:4B:71:00 (public), reason 0x08 
[00:00:21.655,609] <inf> main: Direct advertising to 14:5A:FC:4B:71:00 (public) started
[00:00:22.935,699] <inf> main: Direct advertising to 14:5A:FC:4B:71:00 (public) timed out
[00:00:22.946,166] <inf> main: Regular advertising started

Here's the log:

Security error is 9
Pairing error is 9
disconnection reason is 8

A connection attempt is made from a Linux machine about 10 seconds after startup.
On the Linux machine, a key code popup appears for about 0.5 seconds and then disappears immediately.

I would appreciate any advice you can give me.

[Edvin]

It could be that one of the devices (the nRF or your computer) have the bonding data stored, but the other one doesn't.

Make sure that you remove the device from your computer (if you tried another sample on the DK previously, look for that device as well), and remove it from "known/paired" devices.

Then make sure the flash on your nRF52840 is empty. You can use either of these:

nrfutil device erase

nrfjprog --eraseall

And then flash the application again. If the same issue still occurs, can you please try to capture a sniffer trace of the connection? You can use the nRF Sniffer for Bluetooth LE for this. 

Best regards,

Edvin