Error 14 (0xe): GATT ERR UNLIKELY

[IvanR]

After sending a notification that is less than the negotiated MTU. It is less than 20 bytes

It occurs sporadically. 

I 10:26:08.450 Notification received from 15ff1845-05d3-4c5b-8281-93d4e07420cf, value: (0x) 30-2E-30-30-2C-2D-30-2E-30-30-2C-30-2E-30-32, "0.00,-0.00,0.02"
A 10:26:08.450 "(0x) 30-2E-30-30-2C-2D-30-2E-30-30-2C-30-2E-30-32, "0.00,-0.00,0.02"" received
I 10:26:08.453 Notification received from 15ff1845-05d3-4c5b-8281-93d4e07420cf, value: (0x) 30-2E-30-31-2C-2D-30-2E-30-30-2C-30-2E-30-34, "0.01,-0.00,0.04"
A 10:26:08.453 "(0x) 30-2E-30-31-2C-2D-30-2E-30-30-2C-30-2E-30-34, "0.01,-0.00,0.04"" received
I 10:26:08.457 Notification received from 15ff1845-05d3-4c5b-8281-93d4e07420cf, value: (0x) 30-2E-30-30-2C-2D-30-2E-30-30-2C-30-2E-30-33, "0.00,-0.00,0.03"
A 10:26:08.457 "(0x) 30-2E-30-30-2C-2D-30-2E-30-30-2C-30-2E-30-33, "0.00,-0.00,0.03"" received
E 10:26:08.458 Error 14 (0xe): GATT ERR UNLIKELY

I use nRF Connect app for testing on Android.

[Vidar Berg]

Hello,

Is the log above from nRF Connect or your nRF5340 board? Also, after getting the GATT error, do you stop receiving notifications?

Thanks,

Vidar

[IvanR]

The log is from nRf Connect app. 

No, notifications keep going

[Vidar Berg]

So this could potentially be a bug in the Android phone. Have you been able to reproduce this with different phones?

[IvanR]

it also showed up in dev app on a different phone

[Vidar Berg]

Please provide a sniffer trace showing the packet exchange when this error is reported. It would also be interesting to know if you are able to reproduce this with any of the SDK examples. 

[IvanR]

Wireshark and nrf52840 dongle don't see those packets. 

[IvanR]

Frame 3478: 35 bytes on wire (280 bits), 35 bytes captured (280 bits) on interface COM36-4.2, id 0
    Section number: 1
    Interface id: 0 (COM36-4.2)
        Interface name: COM36-4.2
        Interface description: nRF Sniffer for Bluetooth LE COM36
    Encapsulation type: nRF Sniffer for Bluetooth LE (186)
    Arrival Time: Nov 23, 2023 12:07:47.818196000 Central European Standard Time
    UTC Arrival Time: Nov 23, 2023 11:07:47.818196000 UTC
    Epoch Arrival Time: 1700737667.818196000
    [Time shift for this packet: 0.000000000 seconds]
    [Time delta from previous captured frame: 0.000230000 seconds]
    [Time delta from previous displayed frame: 0.011480000 seconds]
    [Time since reference or first frame: 24.821341000 seconds]
    Frame Number: 3478
    Frame Length: 35 bytes (280 bits)
    Capture Length: 35 bytes (280 bits)
    [Frame is marked: False]
    [Frame is ignored: False]
    [Protocols in frame: nordic_ble:btle:btl2cap:btatt]
nRF Sniffer for Bluetooth LE
    Board: 36
    Header Version: 3, Packet counter: 47146
        Length of payload: 28
        Protocol version: 3
        Packet counter: 47146
        Packet ID: 6
    Length of packet: 10
    Flags: 0x01
        .... ...1 = CRC: Ok
        .... ..0. = Direction: Slave -> Master
        .... .0.. = Encrypted: No
        .... 0... = MIC (not relevant): 0
        .000 .... = PHY: LE 1M (0)
        0... .... = Reserved: 0
    Channel Index: 23
    RSSI: -48 dBm
    Event counter: 1681
    Timestamp: 1491198514µs
    [Packet time (start to end): 152µs]
    [Delta time (end to start): 150µs]
    [Delta time (start to start): 230µs]
Bluetooth Low Energy Link Layer
    Access Address: 0x9c124f94
    [Master Address: 52:12:d5:6c:bf:9a (52:12:d5:6c:bf:9a)]
    [Slave Address: f8:a4:c9:d7:48:fd (f8:a4:c9:d7:48:fd)]
    Data Header
        .... ..10 = LLID: Start of an L2CAP message or a complete L2CAP message with no fragmentation (0x2)
        .... .1.. = Next Expected Sequence Number: 1 [ACK]
        .... 0... = Sequence Number: 0 [OK]
        ...0 .... = More Data: False
        ..0. .... = CTE Info: Not Present
        00.. .... = RFU: 0
        Length: 9
    [L2CAP Index: 60]
    [Connection Parameters in: 551]
    CRC: 0x38ef92
Bluetooth L2CAP Protocol
    Length: 5
    CID: Attribute Protocol (0x0004)
Bluetooth Attribute Protocol
    Opcode: Error Response (0x01)
        0... .... = Authentication Signature: False
        .0.. .... = Command: False
        ..00 0001 = Method: Error Response (0x01)
    Request Opcode in Error: Write Request (0x12)
        0... .... = Authentication Signature: False
        .0.. .... = Command: False
        ..01 0010 = Method: Write Request (0x12)
    Handle in Error: 0x0012 (Unknown: Unknown)
        [Service UUID: 25ae144105d34c5b828193d4e07420cf]
        [UUID: 25ae144205d34c5b828193d4e07420cf]
    Error Code: Unlikely Error (0x0e)

[Vidar Berg]

Please post the sniffer capture file.

[IvanR]

Im sorry but I can not share that file with you