Modify BLE Advertising tutorial to change advertising data on button press

[calebt]

Hello, I've been tinkering around with the BLE Advertising tutorial on my nRF52840 Dongle (using SoftDevice 140) and I have a question:

How do I configure the dongle's user button to change the advertising data on press?

Currently, I've modified prepended some code to one of the functions in `main.c`

static void bsp_event_handler(bsp_event_t event)
{
    ret_code_t err_code;

    ble_gap_adv_data_t my_data;
    uint8_t data[]                            = "New!"; // New data to advertise
    my_data.adv_data.p_data = data;
    my_data.adv_data.len = sizeof(data);

    sd_ble_gap_adv_set_configure(&(m_advertising.adv_handle), &my_data, NULL); // Update existing advertising data
    
    // The rest of the original function is still here
}

I scan for the Dongle with nRF Connect on my phone--it shows up with the original advertising data and does not update to "New!" even when I press the button.

I'm new to the Nordic nRF family; is there something I'm missing?  Help would be greatly appreciated.

Thank you!

[Vidar Berg]

Hi,

You need to encode the data to construct a valid advertisement packet. The ble_advdata_encode() function my be used for this. Try to see if the code below works for you.

#define APP_COMPANY_IDENTIFIER          0x0059                      /**< Company identifier for Nordic Semiconductor ASA. as per www.bluetooth.org. */

static uint8_t   m_encoded_data[2][BLE_GAP_ADV_SET_DATA_SIZE_MAX];  /**< Buffer for storing an encoded advertising set. */

/**@brief Struct that contains pointers to the encoded advertising data. */
static ble_gap_adv_data_t m_adv_data =
{
    .adv_data =
    {
        .p_data = m_encoded_data[0],
        .len    = BLE_GAP_ADV_SET_DATA_SIZE_MAX
    },
    .scan_rsp_data =
    {
        .p_data = NULL,
        .len    = 0

    }
};

void bsp_event_handler()
{

    ret_code_t               err_code;
    ble_advdata_t            mydata;
    ble_advdata_manuf_data_t manuf_specific_data;

    uint8_t data[] = "New!"; //data to include in the manufacturer field
    

    manuf_specific_data.data.p_data = data;
    manuf_specific_data.data.size   = sizeof(data);
    manuf_specific_data.company_identifier = APP_COMPANY_IDENTIFIER; // company identifier is required

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

    mydata.flags = BLE_GAP_ADV_FLAG_BR_EDR_NOT_SUPPORTED;
    mydata.p_manuf_specific_data = &manuf_specific_data;

    /*swap adv data buffer - from API doc: "In order to update advertising 
    data while advertising,new advertising buffers must be provided"*/
    m_adv_data.adv_data.p_data = (m_adv_data.adv_data.p_data == m_encoded_data[0])
                                ? m_encoded_data[1] : m_encoded_data[0];

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


    err_code = sd_ble_gap_adv_set_configure(&(m_advertising.adv_handle), &m_adv_data, NULL);
    APP_ERROR_CHECK(err_code);
}

[calebt]

This did it!  Thank you Vidar Berg ! And just to round things out a bit: anyone wanting to maintain the Bluetooth device name on the advertisement should also set the following inside Vidar's modified bsp_event_handler():

mydata.name_type = BLE_ADVDATA_SHORT_NAME; // or something else from the enum
mydata.short_name_len = 6; // or whatever other length you picked

[stecla]

Could you share your whole main.c file? I would like to have a look for inspiration

[dewal]

 i am facing issue ,please Could you share your whole main.c file? I would like to have a look for inspiration