Can't connect to peripheral

RE: Can't connect to peripheral

Simonr — Fri, 16 Apr 2021 10:07:53 GMT

Are you saying that it works as intended now that you're setting filters with the nrf_ble_scan_filter_set() function and the issue is resolved, or does the problem still persist with this nrf_ble_scan_init() function?

If it's resolved, feel free to verify your answer to mark this case as solved.

Best regards,

Simon

RE: Can't connect to peripheral

QuentinFarizon — Thu, 15 Apr 2021 12:22:12 GMT

Thank you, it works like this :

    err_code = nrf_ble_scan_init(&m_scan, &init_scan, scan_evt_handler);
    APP_ERROR_CHECK(err_code);

    err_code = nrf_ble_scan_filter_set(&m_scan,
                                       SCAN_NAME_FILTER,
                                       "Bala");
    APP_ERROR_CHECK(err_code);

    err_code = nrf_ble_scan_filters_enable(&m_scan,
                                           NRF_BLE_SCAN_NAME_FILTER,
                                           true);
    APP_ERROR_CHECK(err_code);

RE: Can't connect to peripheral

Simonr — Mon, 12 Apr 2021 06:31:43 GMT

In your init function here, it seems like you enable all filters, which might cause some issues for you Please try setting this to NRF_BLE_SCAN_NAME_FILTER. Can you also show me how the device name is set in your peripheral device?

From what I can see, this scan_init should let you connect to a peripheral advertising with the device name Bala.

Best regards,

Simon

RE: Can't connect to peripheral

QuentinFarizon — Fri, 09 Apr 2021 13:50:36 GMT

Sorry for the XY problem :)
Indeed, my goal is connecting to a device by its name, with a filter set. As it was not working, I tried the above, but I understand now why it didn't work.

Here was my filtering code that doesn't connect to my peripheral.
"Bala" is the name of mu peripheral, I see it in nRF connect and can connect to it.

static void scan_init(void)
{
    ret_code_t err_code;
    nrf_ble_scan_init_t init_scan;

    memset(&init_scan, 0, sizeof(init_scan));

    init_scan.p_scan_param     = &m_scan_param;
    init_scan.connect_if_match = true;
    init_scan.conn_cfg_tag     = APP_BLE_CONN_CFG_TAG;

    err_code = nrf_ble_scan_init(&m_scan, &init_scan, scan_evt_handler);
    APP_ERROR_CHECK(err_code);

    err_code = nrf_ble_scan_filter_set(&m_scan,
                                       SCAN_NAME_FILTER,
                                       "Bala");
    APP_ERROR_CHECK(err_code);

    err_code = nrf_ble_scan_filters_enable(&m_scan,
                                           NRF_BLE_SCAN_ALL_FILTER,
                                           true);
    APP_ERROR_CHECK(err_code);
}

Here are the logs :

00> <debug> ble_scan: Adding filter on Bala name
00> <debug> ble_scan: BLE_GAP_SCAN_TIMEOUT
00> <info> app: Scan timed out.
00> <debug> ble_scan: Scanning parameters have been changed successfully
00> <debug> ble_scan: Scanning
00> <debug> ble_scan: BLE_GAP_SCAN_TIMEOUT

RE: Can't connect to peripheral

Simonr — Fri, 09 Apr 2021 07:29:19 GMT

When you have the init_scan.connect_if_match = true; set in your scan_init, the scan module automatically conencts after a filter match or successful identification of a device from the whitelist. So if you don't have any filters added to your whitelist, you won't connect to any devices at all. If you add multiple filters (I.E. all the services you would like to connect to) in your scanning module the connect_if_match should connect to the first discovered device matching any criteria.

I would suggest checking out the scanning module in the SDK to get more information on I.E. filters, triggering connections from scanning, etc. What exactly is your goal here? Just connecting to the first discovered advertising device doesn't seem like the ultimate use case.

Best regards,

Simon