BLE UART custom service

RE: BLE UART custom service

Einar Thorsrud — Fri, 17 Nov 2023 12:55:01 GMT

I am not aware of any updates here, though this thread may be related. If you have a similar issue I suggest you open a new case.

RE: BLE UART custom service

Allen_ — Fri, 17 Nov 2023 12:42:13 GMT

Hi Einar Thorsrud

Is there a good solution to this problem? Thank you

RE: BLE UART custom service

Einar Thorsrud — Fri, 09 Jul 2021 14:01:24 GMT

Hi,

[quote user="JARM"]Hi, I have already do this in the example project ( #define NRF_SDH_BLE_VS_UUID_COUNT 10) .[/quote]

I see that in some sdk_config.h files now when I diff, but it was not set in TEST\examples\ble_central\ble_app_uart_c\pca10056\s140\ses project. Perhaps it was a wrong assumption that it was what you used, but I saw it included build files. Please specify which exact project you use so that I know I am using the correct one.

[quote user="JARM"]My error is not a memory problem but a problem about disovering or enable notification (i don't know witch one).[/quote]

Also, please explain in detail how to reproduce the issue using your code.

Looking at you rcode again I see one obvious issue. Take this whole section where all UUID baes are added:

    err_code = sd_ble_uuid_vs_add(&nus_base_uuid, &p_ble_nus_c->uuid_type);
    VERIFY_SUCCESS(err_code);

    //AJOUT
    
    ble_uuid128_t tx_base_uuid = {BLE_UUID_COMMANDE_TX_UUID};
    VERIFY_PARAM_NOT_NULL(p_ble_nus_c);
    VERIFY_PARAM_NOT_NULL(p_ble_nus_c_init);
    err_code = sd_ble_uuid_vs_add(&tx_base_uuid, &p_ble_nus_c->uuid_type);
    VERIFY_SUCCESS(err_code);

    ble_uuid128_t rx_base_uuid = {BLE_UUID_COMMANDE_RX_UUID};
    VERIFY_PARAM_NOT_NULL(p_ble_nus_c);
    VERIFY_PARAM_NOT_NULL(p_ble_nus_c_init);
    err_code = sd_ble_uuid_vs_add(&rx_base_uuid, &p_ble_nus_c->uuid_type);
    VERIFY_SUCCESS(err_code);
    
    // FIN AJOUT

Here you add three bases, but you store the ID in the same variable (&p_ble_nus_c->uuid_type), overwriting the first two. you need to store all three so that they can be referenced later. The way this is now, you use the last base UUID you add so when searching for the NUS UUID in ble_nus_c_on_db_disc_evt, you are actually searching for the type (base) BLE_UUID_COMMANDE_RX_UUID. And that is not going to wok.

FYI: I am starting my 3 weeks vacation now so there may be delays in this thread. If you need more support before it might be a good idea to open a new case.

RE: BLE UART custom service

JARM — Fri, 09 Jul 2021 13:30:21 GMT

Hi, I have already do this in the example project ( #define NRF_SDH_BLE_VS_UUID_COUNT 10) .

My error is not a memory problem but a problem about disovering or enable notification (i don't know witch one).

When you download my project, you can connect to a peripheral board and exchange uart over BLE data?

This is my log in central side:

with line 158 to 168 enable:

<info> app_timer: RTC: initialized.
<debug> ble_scan: Added filter on UUID 4778
<info> app: BLE UART central example started.
<debug> ble_scan: Scanning
<info> app_timer: RTC: initialized.
<debug> ble_scan: Added filter on UUID 4778
<info> app: BLE UART central example started.
<debug> ble_scan: Scanning
<debug> ble_scan: Connecting
<debug> ble_scan: Connection status: 0
<debug> nrf_ble_gatt: Requesting to update ATT MTU to 247 bytes on connection 0x0.
<debug> nrf_ble_gatt: Updating data length to 251 on connection 0x0.
<info> app: Connecting to target 77A9B2E712E4
<debug> nrf_ble_gq: Registering connection handle: 0x0000
<debug> ble_db_disc: Starting discovery of service with UUID 0x4778 on connection handle 0x0.
<debug> nrf_ble_gq: Adding item to the request queue
<debug> nrf_ble_gq: GATTC Primary Services Discovery Request
U of 247 bytes.
<debug> nrf_ble_gatt: Updating ATT MTU to 247 bytes (desired: 247) on connection 0x0.
<debug> nrf_ble_gq: Processing the request queue...
<debug> nrf_ble_gq: GATTC Primary Service Discovery Request
<debug> nrf_ble_gq: SD is currently busy. The GATT request procedure will be attempted                           again later.
<debug> nrf_ble_gatt: ATT MTU updated to 247 bytes on connection 0x0 (response).
<info> app: ATT MTU exchange completed.
<info> app: Ble NUS max data length set to 0xF4(244)
<debug> nrf_ble_gq: Processing the request queue...
<debug> nrf_ble_gq: GATTC Primary Service Discovery Request
<debug> nrf_ble_gq: SD GATT procedure (2) succeeded on connection handle: 0.
<debug> nrf_ble_gatt: Data length updated to 251 on connection 0x0.
<debug> nrf_ble_gatt: max_rx_octets: 251
<debug> nrf_ble_gatt: max_tx_octets: 251
<debug> nrf_ble_gatt: max_rx_time: 2120
<debug> nrf_ble_gatt: max_tx_time: 2120
<debug> ble_db_disc: Service UUID 0x4778 not found.
<debug> nrf_ble_gq: Processing the request queue...

with bloc line move just before "return ble_db_discovery_evt_register(&uart_uuid);:"

<info> app_timer: RTC: initialized.
<debug> ble_scan: Added filter on UUID 4778
<info> app: BLE UART central example started.
<debug> ble_scan: Scanning
<debug> ble_scan: Connecting
<debug> ble_scan: Connection status: 0
<debug> nrf_ble_gatt: Requesting to update ATT MTU to 247 bytes on connection 0x0.
<debug> nrf_ble_gatt: Updating data length to 251 on connection 0x0.
<info> app: Connecting to target 77A9B2E712E4
<debug> nrf_ble_gq: Registering connection handle: 0x0000
<debug> ble_db_disc: Starting discovery of service with UUID 0x4778 on connection handle 0x0.
<debug> nrf_ble_gq: Adding item to the request queue
<debug> nrf_ble_gq: GATTC Primary Services Discovery Request
<debug> nrf_ble_gq: SD is currently busy. The GATT request procedure will be attempted                       again later.
<debug> nrf_ble_gq: Processing the request queue...
U of 247 bytes.
<debug> nrf_ble_gatt: ATT MTU updated to 247 bytes on connection 0x0 (response).
<info> app: ATT MTU exchange completed.
<info> app: Ble NUS max data length set to 0xF4(244)
<debug> nrf_ble_gq: Processing the request queue...
<debug> nrf_ble_gq: GATTC Primary Service Discovery Request
<debug> nrf_ble_gq: SD GATT procedure (2) succeeded on connection handle: 0.
<debug> nrf_ble_gatt: Data length updated to 251 on connection 0x0.
<debug> nrf_ble_gatt: max_rx_octets: 251
<debug> nrf_ble_gatt: max_tx_octets: 251
<debug> nrf_ble_gatt: max_rx_time: 2120
<debug> nrf_ble_gatt: max_tx_time: 2120
<debug> ble_db_disc: Found service UUID 0x4778.
<debug> nrf_ble_gq: Adding item to the request queue
<debug> nrf_ble_gq: GATTC Characteristic Discovery Request
<debug> nrf_ble_gq: SD GATT procedure (3) succeeded on connection handle: 0.
<debug> nrf_ble_gq: Processing the request queue...
<debug> nrf_ble_gq: Adding item to the request queue
<debug> nrf_ble_gq: GATTC Characteristic Discovery Request
<debug> nrf_ble_gq: SD GATT procedure (3) succeeded on connection handle: 0.
<debug> nrf_ble_gq: Processing the request queue...
<debug> nrf_ble_gq: Adding item to the request queue
<debug> nrf_ble_gq: GATTC Characteristic Descriptor Request
<debug> nrf_ble_gq: SD GATT procedure (4) succeeded on connection handle: 0.
<debug> nrf_ble_gq: Processing the request queue...
<debug> nrf_ble_gq: Adding item to the request queue
<debug> nrf_ble_gq: GATTC Characteristic Descriptor Request
<debug> nrf_ble_gq: SD GATT procedure (4) succeeded on connection handle: 0.
<debug> nrf_ble_gq: Processing the request queue...
<debug> ble_db_disc: Discovery of service with UUID 0x4778 completed with success on connection handle 0x0.
<debug> nrf_ble_gq: Processing the request queue...

But no "Discovery complete." message... So, I can't exchange data over BLE

with line commented:

<info> app_timer: RTC: initialized.
<debug> ble_scan: Added filter on UUID 4778
<info> app: BLE UART central example started.
<debug> ble_scan: Scanning
<debug> ble_scan: Connecting
<debug> ble_scan: Connection status: 0
<debug> nrf_ble_gatt: Requesting to update ATT MTU to 247 bytes on connection 0x0.
<debug> nrf_ble_gatt: Updating data length to 251 on connection 0x0.
<info> app: Connecting to target 77A9B2E712E4
<debug> nrf_ble_gq: Registering connection handle: 0x0000
<debug> ble_db_disc: Starting discovery of service with UUID 0x4778 on connection handle 0x0.
<debug> nrf_ble_gq: Adding item to the request queue
<debug> nrf_ble_gq: GATTC Primary Services Discovery Request
<debug> nrf_ble_gq: SD is currently busy. The GATT request proceU of 247 bytes.
7) on connection 0x0.
<debug> nrf_ble_gq: Processing the request queue...
<debug> nrf_ble_gq: GATTC Primary Service Discovery Request
<debug> nrf_ble_gq: SD is currently busy. The GATT request procedure will be attempted                           again later.
<debug> nrf_ble_gatt: ATT MTU updated to 247 bytes on connection 0x0 (response).
<info> app: ATT MTU exchange completed.
<info> app: Ble NUS max data length set to 0xF4(244)
<debug> nrf_ble_gq: Processing the request queue...
<debug> nrf_ble_gq: GATTC Primary Service Discovery Request
<debug> nrf_ble_gq: SD GATT procedure (2) succeeded on connection handle: 0.
<debug> nrf_ble_gatt: Data length updated to 251 on connection 0x0.
<debug> nrf_ble_gatt: max_rx_octets: 251
<debug> nrf_ble_gatt: max_tx_octets: 251
<debug> nrf_ble_gatt: max_rx_time: 2120
<debug> nrf_ble_gatt: max_tx_time: 2120
<debug> ble_db_disc: Found service UUID 0x4778.
<debug> nrf_ble_gq: Adding item to the request queue
<debug> nrf_ble_gq: GATTC Characteristic Discovery Request
<debug> nrf_ble_gq: SD GATT procedure (3) succeeded on connection handle: 0.
<debug> nrf_ble_gq: Processing the request queue...
<debug> nrf_ble_gq: Adding item to the request queue
<debug> nrf_ble_gq: GATTC Characteristic Discovery Request
<debug> nrf_ble_gq: SD GATT procedure (3) succeeded on connection handle: 0.
<debug> nrf_ble_gq: Processing the request queue...
<debug> nrf_ble_gq: Adding item to the request queue
<debug> nrf_ble_gq: GATTC Characteristic Descriptor Request
<debug> nrf_ble_gq: SD GATT procedure (4) succeeded on connection handle: 0.
<debug> nrf_ble_gq: Processing the request queue...
<debug> nrf_ble_gq: Adding item to the request queue
<debug> nrf_ble_gq: GATTC Characteristic Descriptor Request
<debug> nrf_ble_gq: SD GATT procedure (4) succeeded on connection handle: 0.
<debug> nrf_ble_gq: Processing the request queue...
<debug> ble_db_disc: Discovery of service with UUID 0x4778 completed with success on connection handle 0x0.
<info> app: Discovery complete.
<info> app_timer: RTC: initialized.
<debug> ble_scan: Added filter on UUID 4778
<info> app: BLE UART central example started.
<debug> ble_scan: Scanning
<debug> ble_scan: Connecting
<debug> ble_scan: Connection status: 0
<debug> nrf_ble_gatt: Requesting to update ATT MTU to 247 bytes on connection 0x0.
<debug> nrf_ble_gatt: Updating data length to 251 on connection 0x0.
<info> app: Connecting to target 77A9B2E712E4
<debug> nrf_ble_gq: Registering connection handle: 0x0000
<debug> ble_db_disc: Starting discovery of service with UUID 0x4778 on connection handle 0x0.
<debug> nrf_ble_gq: Adding item to the request queue
<debug> nrf_ble_gq: GATTC Primary Services Discovery Request
U of 247 bytes.
7) on connection 0x0.
<debug> nrf_ble_gq: Processing the request queue...
<debug> nrf_ble_gq: GATTC Primary Service Discovery Request
<debug> nrf_ble_gq: SD is currently busy. The GATT request procedure will be attempted                           again later.
<debug> nrf_ble_gatt: ATT MTU updated to 247 bytes on connection 0x0 (response).
<info> app: ATT MTU exchange completed.
<info> app: Ble NUS max data length set to 0xF4(244)
<debug> nrf_ble_gq: Processing the request queue...
<debug> nrf_ble_gq: GATTC Primary Service Discovery Request
<debug> nrf_ble_gq: SD GATT procedure (2) succeeded on connection handle: 0.
<debug> nrf_ble_gatt: Data length updated to 251 on connection 0x0.
<debug> nrf_ble_gatt: max_rx_octets: 251
<debug> nrf_ble_gatt: max_tx_octets: 251
<debug> nrf_ble_gatt: max_rx_time: 2120
<debug> nrf_ble_gatt: max_tx_time: 2120
<debug> ble_db_disc: Found service UUID 0x4778.
<debug> nrf_ble_gq: Adding item to the request queue
<debug> nrf_ble_gq: GATTC Characteristic Discovery Request
<debug> nrf_ble_gq: SD GATT procedure (3) succeeded on connection handle: 0.
<debug> nrf_ble_gq: Processing the request queue...
<debug> nrf_ble_gq: Adding item to the request queue
<debug> nrf_ble_gq: GATTC Characteristic Discovery Request
<debug> nrf_ble_gq: SD GATT procedure (3) succeeded on connection handle: 0.
<debug> nrf_ble_gq: Processing the request queue...
<debug> nrf_ble_gq: Adding item to the request queue
<debug> nrf_ble_gq: GATTC Characteristic Descriptor Request
<debug> nrf_ble_gq: SD GATT procedure (4) succeeded on connection handle: 0.
<debug> nrf_ble_gq: Processing the request queue...
<debug> nrf_ble_gq: Adding item to the request queue
<debug> nrf_ble_gq: GATTC Characteristic Descriptor Request
<debug> nrf_ble_gq: SD GATT procedure (4) succeeded on connection handle: 0.
<debug> nrf_ble_gq: Processing the request queue...
<debug> ble_db_disc: Discovery of service with UUID 0x4778 completed with success on connection handle 0x0.
<info> app: Discovery complete.
<error> app: ERROR 8 [NRF_ERROR_INVALID_STATE] at C:\Users\julien.HORIZONTELECOM\Downloads\TEST\examples\ble_central\ble_app_uart_c\main.c:336
PC at: 0x0002F797
<error> app: End of error report

RE: BLE UART custom service

Einar Thorsrud — Fri, 09 Jul 2021 13:12:21 GMT

Hi,

I used a debug build (selected "Debug" from the build configuration drop-down menu) to get better logging, and I include the code from line 158 to 169 in ble_nus_c.c. Then I got the following RTT log:

<info> app_timer: RTC: initialized.
<error> app: ERROR 4 [NRF_ERROR_NO_MEM] at C:\Users\eith\Downloads\TEST\examples\ble_central\ble_app_uart_c\main.c:585
PC at: 0x00030A1B
<error> app: End of error report

This makes sense as you add two new vendor specific UUIDs. Then the first step is to open sdk_config.h and increase NRF_SDH_BLE_VS_UUID_COUNT to 3. Build and test again. That fails as expected as the adjustment increased the SoftDevice RAM usage. However, the debug log again gives useful information:

<info> app_timer: RTC: initialized.
<warning> nrf_sdh_ble: Insufficient RAM allocated for the SoftDevice.
<warning> nrf_sdh_ble: Change the RAM start location from 0x20002A38 to 0x20002A58.
<warning> nrf_sdh_ble: Maximum RAM size for application is 0x3D5A8.
<error> nrf_sdh_ble: sd_ble_enable() returned NRF_ERROR_NO_MEM.
<error> app: ERROR 4 [NRF_ERROR_NO_MEM] at C:\Users\eith\Downloads\TEST\examples\ble_central\ble_app_uart_c\main.c:487
PC at: 0x0003084B
<error> app: End of error report

Now, we adjust the configuration as instructed by the error message:

When building and testing again there is no error.

RE: BLE UART custom service

JARM — Fri, 09 Jul 2021 12:28:33 GMT

After some test,

If yout test with the enable bloc code (bloc between "// ADD ... code ... //END OF ADD) in the ble_nus_c_init () function, you have the message "Service UUID 0x4778 not found"

If you move the bloc code before this line "p_ble_nus_c->p_gatt_queue = p_ble_nus_c_init->p_gatt_queue;" discover works (service is found) but notification are not enable becuse of " Processing the request queu..."

Thanks

RE: BLE UART custom service

JARM — Fri, 09 Jul 2021 08:25:24 GMT

I restart a central and peripheral project from the example because my project is not very clear.

For the peripheral, you can flash a PAC10056 DK with the "examples/ble_peripheral/ble_app_uart" project.
You can verify with a smartphone to see that peripheral works well.

For the central, you can flash a PAC10040 DK with the "examples/ble_central/ble_app_uart_c" project.

I have add some line in ble_nus_c_init().
If you comment this bloc, you can see the notification problem.
If you enable this line (I add them today for some test), notification problems disappear because "BLE_NUS_C_EVT_DISCOVERY_COMPLETE" is not reach. I don't now if it's a begin of solution...

Here, the link for all the project:

https://drive.google.com/file/d/1PED-x1oAy6tT0mK8qnOmPk2jTyK1H4lQ/view?usp=sharing

RE: BLE UART custom service

Einar Thorsrud — Thu, 08 Jul 2021 14:14:27 GMT

That is odd... Did you debug to see what happens when you write "software crash"? If you can share your code and it runs on a DK, then I can test on my side as well.

RE: BLE UART custom service

JARM — Thu, 08 Jul 2021 13:15:06 GMT

Exact, I want to do the exact same as NUS but with different UUID in Nus SERVICE (128 bits) and two differents characteristics UUID (128 bits).

When I start the application, the central is scanning and connecting to the peripheral. The discover process start but in ble_nus_c_on_db_disc_evt() the p_chars[i].characteristic.uuid.uuid are null for the two characteristics and the event BLE_NUS_C_EVT_DISCOVERY_COMPLETE is done.

On the ble_nus_c_evt_handler() function, the event BLE_NUS_C_EVT_DISCOVERY_COMPLETE is reach and the problem is on the err_code = ble_nus_c_tx_notif_enable(p_ble_nus_c) line with error code = 8 because p_ble_nus_c->handles.nus_tx_cccd_handle == BLE_GATT_HANDLE_INVALID..

I think characteristics are not really fine discoverred during the scan process.

I have cheat in the function ble_nus_c_on_db_disc_evt() by adding condition and forcing the uuid value but is not a good solution.

void ble_nus_c_on_db_disc_evt(ble_nus_c_t * p_ble_nus_c, ble_db_discovery_evt_t * p_evt)
{
    ble_nus_c_evt_t nus_c_evt;
    memset(&nus_c_evt,0,sizeof(ble_nus_c_evt_t));

    ble_gatt_db_char_t * p_chars = p_evt->params.discovered_db.charateristics;

    // Check if the NUS was discovered.
    if (    (p_evt->evt_type == BLE_DB_DISCOVERY_COMPLETE)
        &&  (p_evt->params.discovered_db.srv_uuid.uuid == BLE_UUID_COMMANDE_SERVICE)   //BLE_UUID_NUS_SERVICE)
        &&  (p_evt->params.discovered_db.srv_uuid.type == p_ble_nus_c->uuid_type))
    {
        NRF_LOG_INFO("nbr: %x",  p_evt->params.discovered_db.char_count);
        for (uint32_t i = 0; i < p_evt->params.discovered_db.char_count; i++)
        {
        
            if( p_evt->params.discovered_db.charateristics[i].characteristic.handle_value == 0x0010)
            {
              p_evt->params.discovered_db.charateristics[i].characteristic.uuid.uuid = BLE_UUID_COMMANDE_RX_CHARACTERISTIC;
              p_chars[i].characteristic.uuid.uuid =p_evt->params.discovered_db.charateristics[i].characteristic.uuid.uuid;

            }else if( p_evt->params.discovered_db.charateristics[i].characteristic.handle_value == 0x000D)
            {
              p_evt->params.discovered_db.charateristics[i].characteristic.uuid.uuid = BLE_UUID_COMMANDE_TX_CHARACTERISTIC;
              p_chars[i].characteristic.uuid.uuid =p_evt->params.discovered_db.charateristics[i].characteristic.uuid.uuid;
            }
            
            NRF_LOG_INFO("uuid: %x", p_chars[i].characteristic.uuid.uuid);
            NRF_LOG_INFO("ccd: %x", p_chars[i].cccd_handle);
            NRF_LOG_INFO("handle_value: %x", p_chars[i].characteristic.handle_value);

RE: BLE UART custom service

Einar Thorsrud — Thu, 08 Jul 2021 12:58:25 GMT

Hi,

The way I read your post you want to do the exact same as the NUS central/client example, just with modified UUID's. Is that correct? If so, you should not need to change anything other than the UUID's itself including the base UUID. Perhaps you can explain what you have done, and what you found when debugging? If there is an error that is typically detected by the error handing system in the nRF5 SDK, so by making a debug build (simply select the Debug build target if using SES) and observing the log you should get good information that point sin the right direction.

RE: BLE UART custom service

JARM — Wed, 07 Jul 2021 11:41:37 GMT

I have see this post https://devzone.nordicsemi.com/f/nordic-q-a/40578/discovering-a-vs-uuid-characterisic-but-it-shows-uuid-as-0/158781

but solution is incomplete and not for ble_app_uart example. I think Ineed to add sd_ble_gattc_read() function but I don't know where.