Stop advertising permanantly in nRF52 SDK15.2

[AnthonyThet]

Hi, I am using nRF52 DK with SDK 15.2 and SD132 for my project and use "ble_app_uart" as a reference. In my project, I want to start and stop advertisment manually through UART.

When I received adv_stop command, I use "sd_ble_gap_adv_stop(m_advertising.adv_handle);" to stop advertising. But it's restart advertising from somewhere else.

Even if I put timeout, it automatically restarts advertising. What I want is that it should stop advertising until I run "advertising_start()" again. Please help me how to solve this.

[cbd]

I believe that this code restarts advertising on disconnection, connection terminated events and communication timeout event.

The actual call to start advertising is sd_ble_gap_adv_start, which in the BLE UART app is called from ble_advertising_start in ble_advertising.c

Check out calls to:

on_terminated, on_disconnected and ble_advertising_restart_without_whitelist

[AnthonyThet]

Hi, really thanks for your prompt reply. I checked all these functions (on_terminated, on_disconnected and ble_advertising_restart_without_whitelist) and yes they put advertising start again.

    ret = ble_advertising_start(p_advertising, p_advertising->adv_mode_current);
    if ((ret != NRF_SUCCESS) && (p_advertising->error_handler != NULL))
    {
        p_advertising->error_handler(ret);
    }

    return NRF_SUCCESS;

but how do I control these functions outside of "ble_advertising.c". 
Is there any simple way to manually stop advertising? I tried using ble_advertising_start(BLE_ADV_MODE_IDLE) but since the event BLE_ADV_EVT_IDLE use "sleep_mode_enter()" function which I don't need, I am still struggling with this.

And thanks again for your help.

[cbd]

I've had a quick look again and couldn't initially see where those even triggers are set-up, if at all, but I must ask how do you trigger advertising to start with and are you attempting to debug using breakpoints?

I ask because if you automatically start advertising on power-up (as the example does) and you're using breakpoints for debugging then this will cause the Soft Device to trigger a reset due to BLE timeouts and advertising will restart.

[AnthonyThet]

Hi cbd,

cbd said:

I've had a quick look again and couldn't initially see where those even triggers are set-up, if at all, but I must ask how do you trigger advertising to start with and are you attempting to debug using breakpoints?

I am waiting for the uart command and start advertising when I recieved the command.

cbd said:

I ask because if you automatically start advertising on power-up (as the example does) and you're using breakpoints for debugging then this will cause the Soft Device to trigger a reset due to BLE timeouts and advertising will restart.

No, I run the code in the release mode.

Why the advertisement process seems quite complicated for me? I used ble_app_uart_c as a reference for the central role and I can manage to scan on and off successfully using the uart command. And I also tried to look for the code which calls the advertising_start function but I couldn't find. Please help. 

[cbd]

Hi,

Here's some code from a current project that doesn't rely any library application code.

///############################################################################
/// @fn              BLE_AdvertisingInit
/// @remark          None
/// @return          ret_code_t error code
/// @see Description Initialises the advertising functionality.
///                  Encodes and passes to the BLE stack data that it uses both
///                  before and during advertising
/// @warning
///#############################################################################
ret_code_t BLE_AdvertisingInit(void)
{
    ret_code_t err_code;

    ble_lms_t lms = LMS_GetServiceData();

    /* Data space is limited within the advertising packet. */
    /* Advertise custom service for easy pickup */
    // TODO: maybe replace the data with manufacturing data */
    ble_uuid_t adv_uuids[] = {{LMS_UUID_SERVICE, lms.uuid_type}};


    /* Build and set advertising data */
    ble_advdata_t advdata;
    memset(&advdata, 0, sizeof(advdata));

    advdata.name_type = BLE_ADVDATA_FULL_NAME;
    advdata.include_appearance = true;
    advdata.flags = BLE_GAP_ADV_FLAGS_LE_ONLY_GENERAL_DISC_MODE;

    err_code = ble_advdata_encode(&advdata, m_adv_data.adv_data.p_data, &m_adv_data.adv_data.len);
    APP_ERROR_CHECK(err_code);


    /* Build and set scan response data */
    ble_advdata_t srdata;
    memset(&srdata, 0, sizeof(srdata));
    srdata.uuids_complete.uuid_cnt = sizeof(adv_uuids) / sizeof(adv_uuids[0]);
    srdata.uuids_complete.p_uuids = adv_uuids;

    err_code =
        ble_advdata_encode(&srdata, m_adv_data.scan_rsp_data.p_data, &m_adv_data.scan_rsp_data.len);
    APP_ERROR_CHECK(err_code);

    /* Set advertising parameters */
    ble_gap_adv_params_t adv_params;
    memset(&adv_params, 0, sizeof(adv_params));

    adv_params.primary_phy = BLE_GAP_PHY_1MBPS;
    adv_params.duration = APP_ADV_DURATION;
    adv_params.properties.type = BLE_GAP_ADV_TYPE_CONNECTABLE_SCANNABLE_UNDIRECTED;
    adv_params.p_peer_addr = NULL;
    adv_params.filter_policy = BLE_GAP_ADV_FP_ANY;
    adv_params.interval = APP_ADV_INTERVAL;

    err_code = sd_ble_gap_adv_set_configure(&m_adv_handle, &m_adv_data, &adv_params);
    APP_ERROR_CHECK(err_code);
    return err_code;
}

///############################################################################
/// @fn              BLE_AdvertisingStart
/// @remark          None
/// @return          ret_code_t error code
/// @see Description Triggers BLE advertising through the SoftDevice
/// @warning
///#############################################################################
ret_code_t BLE_AdvertisingStart(void)
{
    ret_code_t err_code;

    err_code = sd_ble_gap_adv_start(m_adv_handle, APP_BLE_CONN_CFG_TAG);
    APP_ERROR_CHECK(err_code);
    NRF_LOG_INFO("BLE Advertising started.");
    return err_code;
}

///############################################################################
/// @fn              BLE_AdvertisingStop
/// @remark          None
/// @return          ret_code_t error code
/// @see Description Terminate BLE advertising through the SoftDevice
/// @warning
///#############################################################################
ret_code_t BLE_AdvertisingStop(void)
{
    ret_code_t err_code = NRF_SUCCESS;

    if (m_adv_handle != BLE_GAP_ADV_SET_HANDLE_NOT_SET)
    {
        NRF_LOG_INFO("BLE Stop advertising.");
        err_code = sd_ble_gap_adv_stop(m_adv_handle);
        if (err_code != NRF_ERROR_INVALID_STATE)
        {
            APP_ERROR_CHECK(err_code);
        }
        m_adv_handle = BLE_GAP_ADV_SET_HANDLE_NOT_SET;
    }

    return err_code;
}

I extracted library app code relating to Bluetooth into my own code file. The above code is what I'm using to set-up, start and stop advertising on my current project.

I hope that this helps.

[AnthonyThet]

Hi cbd, thanks so much for your help, please let me test in my application and get back to you again.

[AnthonyThet]

Hi cbd, I fount out this which I think quite related to my issues. Here I found out ble_advertising_on_ble_evt() function and all the advertising event on termination, disconnection and connection implemented here.

void ble_advertising_on_ble_evt(ble_evt_t const * p_ble_evt, void * p_context)
{
    ble_advertising_t * p_advertising = (ble_advertising_t *)p_context;

    switch (p_ble_evt->header.evt_id)
    {
        case BLE_GAP_EVT_CONNECTED:
            on_connected(p_advertising, p_ble_evt);
            break;

        // Upon disconnection, whitelist will be activated and direct advertising is started.
        case BLE_GAP_EVT_DISCONNECTED:
            on_disconnected(p_advertising, p_ble_evt);
            break;

        // Upon terminated advertising (time-out), the next advertising mode is started.
        case BLE_GAP_EVT_ADV_SET_TERMINATED:
            on_terminated(p_advertising, p_ble_evt);
            break;

        default:
            break;
    }
}

But how can I control these functions not to advertise again? Please help me to solve this and thanks.

[cbd]

Hi,

I don't know if you have solved your problem or not.

on_connected, on_disconnected and on_terminated are just calls to functions to handle behaviour of the advertising when certain Bluetooth events occur.

If you're only triggering advertising based on your UART input then I would be tempted to just comment out the calls to see if that helps.

I suspect that on_connected will just disable advertising.