Unexpected disconnection in Channel Sounding example (nRF SDK)

[nychyporuk]

I am working on the channel sounding feature using two nRF54L15DK boards and faced an unexpected link disconnection while running the channel_sounding_ras_initiator and channel_sounding_ras_reflector samples from the nRF SDK. The examples can run for up to 5 minutes, but the disconnection happens much earlier in most cases.

Here is some information that might be helpful:

*** Booting nRF Connect SDK v2.9.99-989cde884ed8 ***
*** Using Zephyr OS v3.7.99-6e9a5873c5df ***
I: Starting Channel Sounding Initiator Sample
I: SoftDevice Controller build revision:
I: 5e 89 40 59 db 09 d7 b7 |^.@Y....
I: 04 e6 67 8d c1 e3 8c cc |..g.....
I: 0c e1 9c d3             |....    
I: HW Platform: Nordic Semiconductor (0x0002)
I: HW Variant: nRF54Lx (0x0005)
I: Firmware: Standard Bluetooth controller (0x00) Version 94.16521 Build 3607747417
I: Identity: CE:16:77:E3:B5:9A (random)
I: HCI: version 6.0 (0x0e) revision 0x3063, manufacturer 0x0059
I: LMP: version 6.0 (0x0e) subver 0x3063

The console output for the initiator:

I: Estimated distance to reflector:
I: - Round-Trip Timing method: 4.159620 meters (derived from 4 samples)
I: - Phase-Based Ranging method: 2.634659 meters (derived from 35 samples)
I: Subevent result callback 15
I: Ranging data ready 15
E: Error when getting ranging data with ranging counter 15 (err -128)
I: Disconnected (reason 0x08)
E: Timeout waiting for ranging data complete (err -11)

The console output for the reflector:

W: Not connected
W: Failed to send indication: -128
I: Disconnected (reason 0x3D)

I also tried the Zephyr samples channel_sounding/connected_cs/initiator and channel_sounding/connected_cs/reflector and did not encounter the described disconnection.

Can it be the issue with the nRF SDK?

[abestmann]

We do observe similar issues on our side using the examples.

Looking forward to get a solution for this.

[Elfving]

Hello Oleksandr, and abestmann 

So first of all, this is a new sample that you are running on some untagget version of the SDK, this means that there might be issues with the SDK and samples. I would urge you to try it on a tagged version of the SDK if that was an option for you, but ofcourse it isn't for the time being, as this is brand new. If you want something to measure distance that is currently fully supported though, I would recommend you to have a look at the nordic distance toolbox, we have a sample for that here.

So I just tried the channel sounding sample with the main branch and it didn't even build. Did you hear from someone that 989cde884ed8 was particularly worth trying?

Note that your RSMs might be able to tell you more about when NCS 2.9 is available, which is the stable, tagged, version of NCS that supports this.

Regards,

Elfving

[Elfving]

Hi again everyone,

NCS 2.9.0 will be released soon, so when that comes you could also try it there. But I have just had a coworker of mine try this is 2.9.0-rc1, and that should work fine. Could you give rc1 a go?

And what DK versions are you using? My coworker used nRF54L15 DK 0.8.2

Are you moving it around in order to test the distance measuring when this issue occurs? Are they for instance getting out of range?

Regards,

Elfving

[nychyporuk]

Hi Elfving,

I noticed that NCS 2.9.0 has been released, so I tested it with this version.
I am using two nRF54L15 DK 0.9.1 devices placed on a table, approximately 1 meter apart and stationary.
The previously reported issue is no longer reproducible with the new NCS.

Thank you for your continued support!

Best regards,
Oleksandr

[Elfving]

Great! Glad to hear it Oleksander!

Regards,

Elfving