Service discovery, attribute not found 0x0001

RE: Service discovery, attribute not found 0x0001

Bjørn Kvaale — Wed, 19 Jun 2019 07:40:22 GMT

Sorry for the delayed response. I have been on a business trip the past two weeks. From this message sequence chart, you can see that you can use variant 2: discover a specific service if you want to change how service discovery is done. If you take a closer look at the softdevice API, you should be able to modify the service discovery the way you want to.

RE: Service discovery, attribute not found 0x0001

laran — Tue, 04 Jun 2019 21:53:11 GMT

Ok, I am back on this issue and I have my Wireshark up and running gain, so that helps.

Now, when I look at my log in the initial post, the discovery starts with "Sent Find By Type Value Request" starting at 0x0001. All devices that manage to perform a discovery start with a "Sent Read By Group Type Response", then do the "... Find by Type...." based on what was was returned from the "... Read Group Response ..."

My basic question is, if this is something that can be controlled when initializing the service discovery.

RE: Service discovery, attribute not found 0x0001

Bjørn Kvaale — Wed, 13 Jun 2018 11:51:34 GMT

Sorry about the delayed response. Got a tip from a colleague, which was to take a look at the ble heart rate collector central example. I believe the answer should be quite straightforward if you take a look at the ble_app_hrs example:

 * @brief Battery level collector initialization.
 */
static void bas_c_init(void)
{
    ble_bas_c_init_t bas_c_init_obj;

    bas_c_init_obj.evt_handler = bas_c_evt_handler;

    ret_code_t err_code = ble_bas_c_init(&m_bas_c, &bas_c_init_obj);
    APP_ERROR_CHECK(err_code);
}

uint32_t ble_bas_c_init(ble_bas_c_t * p_ble_bas_c, ble_bas_c_init_t * p_ble_bas_c_init)
{
    VERIFY_PARAM_NOT_NULL(p_ble_bas_c);
    VERIFY_PARAM_NOT_NULL(p_ble_bas_c_init);

    ble_uuid_t bas_uuid;

    bas_uuid.type                = BLE_UUID_TYPE_BLE;
    bas_uuid.uuid                = BLE_UUID_BATTERY_SERVICE;

    p_ble_bas_c->conn_handle                = BLE_CONN_HANDLE_INVALID;
    p_ble_bas_c->peer_bas_db.bl_cccd_handle = BLE_GATT_HANDLE_INVALID;
    p_ble_bas_c->peer_bas_db.bl_handle      = BLE_GATT_HANDLE_INVALID;
    p_ble_bas_c->evt_handler                = p_ble_bas_c_init->evt_handler;

    return ble_db_discovery_evt_register(&bas_uuid);
}

Also, take a look at how the BLE_UUID_BATTERY_SERVICE is discovered in the ble_bas_on_db_disc_evt() in ble_bas_c.c.

I would test with the ble_app_hrs example first & when that works (it definitely should), then you can make the relevant changes in the multilink example.

Even though the BLE_UUID_BATTERY_SERVICE is included in ble_srv_common.h, it is not discovered in ble_bas_on_db_disc_evt() or ble_bas_c_init().

RE: Service discovery, attribute not found 0x0001

laran — Thu, 07 Jun 2018 19:23:44 GMT

Yes, I am still using SDK 14.2 with SD s132 (v5.0.0)

This is what I get when printing out the GATT status:
<debug> ble_db_disc: Service UUID 0x180F not found (GATT Status = 0x010A).

RE: Service discovery, attribute not found 0x0001

Bjørn Kvaale — Thu, 07 Jun 2018 07:00:57 GMT

It seems the on_primary_srv_discovery_rsp() function is printing out the "Service UUID 0x0 not found" to the log. The reason for this is that the line "p_ble_gattc_evt->gatt_status" inside the if block of the on_primary_srv_discovery_rsp() function inside ble_db_discovery.c of the multilink example does not return BLE_GATT_STATUS_SUCCESS. Could you set a breakpoint here or print out what the GATT status code is? If you are still using SDK v 14.2 with Softdevice v5.0.0, you can find the different GATT status codes here.

RE: Service discovery, attribute not found 0x0001

laran — Tue, 05 Jun 2018 20:25:31 GMT

I have had major issues with Wireshark. I can't get it to capture anything else then advertisement packages. Occasionally I get a scan request from some Apple device in the area. therefore my logs are useless at the moment. I have tried to recreate the loggs I made earlier without luck.

The best I can do for now is the debug output from the debug output.

<debug> nrf_sdh: State request: 0x00000000
<debug> nrf_sdh: Notify observer 0x00027D78 => ready
<debug> nrf_sdh: State change: 0x00000000
<debug> nrf_sdh: State change: 0x00000001
<debug> nrf_sdh_ble: RAM starts at 0x20004190
<info> app: Multilink example started.
<info> app: Start scanning for device 46 2C 90 17 02 0F
<debug> nrf_sdh_ble: BLE event: 0x1D.
<debug> app: Adv report.
<info> app: Connecting to target 62 CE BB 51 F9 F4
<debug> nrf_sdh_ble: BLE event: 0x1D.
<debug> app: Adv report.
<info> app: Connecting to target 90 63 86 95 13 15
<debug> nrf_sdh_ble: BLE event: 0x1D.
<debug> app: Adv report.
<info> app: Connecting to target 46 2C 90 17 02 0F
<debug> nrf_sdh_ble: BLE event: 0x10.
<info> app: Connection 0x0 established, starting DB discovery.
<debug> ble_db_disc: Starting discovery of service with UUID 0x180F on connection handle 0x0.
<debug> nrf_sdh_ble: BLE event: 0x30.
<debug> ble_db_disc: Service UUID 0x180F not found.
<debug> app: call to ble_lbs_on_db_disc_evt for instance 0 and link 0x0!
<debug> ble_bas_c: Battery Service discovery failure at peer.
<debug> ble_db_disc: Service UUID 0x0 not found.
<debug> ble_db_disc: Service UUID 0x0 not found.
<debug> ble_db_disc: Service UUID 0x0 not found.
<debug> ble_db_disc: Service UUID 0x0 not found.
<debug> ble_db_disc: Service UUID 0x0 not found.
<debug> ble_db_disc: Service UUID 0x0 not found.
<debug> ble_db_disc: Service UUID 0x0 not found.
<debug> nrf_sdh_ble: BLE event: 0x11.
<info> app: LBS central link 0x0 disconnected (reason: 0x8)
<info> app: Start scanning for device 46 2C 90 17 02 0F
<debug> nrf_sdh_ble: BLE event: 0x1D.
<debug> app: Adv report.
<info> app: Connecting to target 59 E1 D5 4E 74 C0
<debug> nrf_sdh_ble: BLE event: 0x1D.
<debug> app: Adv report.
<info> app: Connecting to target 46 2C 90 17 02 0F
<debug> nrf_sdh_ble: BLE event: 0x10.
<info> app: Connection 0x0 established, starting DB discovery.
<debug> ble_db_disc: Starting discovery of service with UUID 0x180F on connection handle 0x0.
<debug> nrf_sdh_ble: BLE event: 0x30.
<debug> ble_db_disc: Service UUID 0x180F not found.
<debug> app: call to ble_lbs_on_db_disc_evt for instance 0 and link 0x0!
<debug> ble_bas_c: Battery Service discovery failure at peer.

RE: Service discovery, attribute not found 0x0001

SRA — Mon, 04 Jun 2018 22:37:32 GMT

Just a heads up that I have a similar issue in another post. Also getting Attribute Not Found for three of my characteristics on discovery. So I'm interested in the response here.

RE: Service discovery, attribute not found 0x0001

Bjørn Kvaale — Mon, 04 Jun 2018 07:43:20 GMT

That's weird. Do you also have any logging information from the multilink example that you could upload? Might be helpful in debugging this further.

RE: Service discovery, attribute not found 0x0001

laran — Mon, 04 Jun 2018 06:29:14 GMT

Just for a quick test I used the multilink central example you suggested. Since it already has the battery service it was perfect for testing this. However, it does not connect here either. I'll uplode a Wireshark log later today.

RE: Service discovery, attribute not found 0x0001

Bjørn Kvaale — Tue, 22 May 2018 08:04:42 GMT

Sorry for the delayed response. I have taken a closer look at the uart central example & I believe this example only searches for the uart service. I think it would be better if you tested with the multilink central example, as that example does not limit itself to the uart service.

RE: Service discovery, attribute not found 0x0001

laran — Wed, 16 May 2018 17:04:44 GMT

I am sorry, I was unclear. nrf Connect is able to do the service discovery on all the printers. My implementation on the nrf52 chip works on some of them. I still expect something is wrong with my code.

When looking at package 520 one can see the the 128 bit service is broadcasted by the printer. Then in package #526 the primary service declaration request is hapening, asking for the same 128 bit value, right? then in #527 the "not found" response happen. Starting at package 35052 one can see how the connection and service discovery between the printer and nrf connect my android device. I interpret it as the printer uses a CSR chip.

I attach a Wireshark log with a device that work. the service discovery starts at package #224

devzone.nordicsemi.com/.../PTP_2D00_II.pcapng

RE: Service discovery, attribute not found 0x0001

Bjørn Kvaale — Wed, 16 May 2018 09:43:47 GMT

What kind of Bluetooth chip do the thermal printers use? If service discovery works using nrf connect, it seems you have done this part correctly. If the thermal printers do not use a Nordic Bluetooth chip, it could be that there is some kind of service discovery error occurring on the server side in the thermal printers.

RE: Service discovery, attribute not found 0x0001

laran — Mon, 14 May 2018 20:58:18 GMT

My project is based on the ble_app_uart_c example with the battery service added to it. I am running Wireshark 2.4.6 using the nrf-sniffer-2.

I have uploaded the Wireshark logg. Go to message 520 for a start.

devzone.nordicsemi.com/.../POS_2D00_5802.pcapng

RE: Service discovery, attribute not found 0x0001

Bjørn Kvaale — Mon, 14 May 2018 09:06:13 GMT

If you take a look at Chapter 3.4.1.1 Error Response in the Bluetooth Core Specification , you can see that the error code 0x0A refers to: "No attribute found within the given attribute handle range". According to this case, this error code is sent for characteristics that do not have a value. Which example from SDK 14.2 are you basing your code off of? Could you upload the whole wireshark log for me to take a look at please? Also, which version of wireshark & nrf sniffer are you currently using?