Can i modify beacon programatically in iOS (Modifying Major & Minor through code) using nRF51822 beacon

[Karthikesh K]

Is there any possibility of modifying UUID, Major, Minor programatically in iOS using nRF51822 beacon

[AmbystomaLabs]

All attributes of an advertisement can be modified on the fly, you do not even need to stop advertising.  Just modify the values you wish and re-init advertising.

[Karthikesh K]

Thank you AmbystomaLabs

[AmbystomaLabs]

Here's an example of doing that.  It is based on SDK11.

Below is the advertising init and then a few lines where one of the parameters was changed.  Just remember the advertising data is little endian so the byte order is reversed.

/**@brief Function for initializing the Advertising functionality.
 *
 * @details Encodes the required advertising data and passes it to the stack.
 *          Also builds a structure to be passed to the stack when starting advertising.
 */

static void advertising_init(uint32_t adv_interval )
{
    uint32_t      err_code;
    ble_advdata_t advdata;
    uint8_t       flags = BLE_GAP_ADV_FLAG_BR_EDR_NOT_SUPPORTED;

    ble_advdata_manuf_data_t manuf_specific_data;

    manuf_specific_data.company_identifier = company_id;

#if defined(USE_UICR_FOR_MAJ_MIN_VALUES)
    // If USE_UICR_FOR_MAJ_MIN_VALUES is defined, the major and minor values will be read from the
    // UICR instead of using the default values. The major and minor values obtained from the UICR
    // are encoded into advertising data in big endian order (MSB First).
    // To set the UICR used by this example to a desired value, write to the address 0x10001080
    // using the nrfjprog tool. The command to be used is as follows.
    // nrfjprog --snr <Segger-chip-Serial-Number> --memwr 0x10001080 --val <your major/minor value>
    // For example, for a major value and minor value of 0xabcd and 0x0102 respectively, the
    // the following command should be used.
    // nrfjprog --snr <Segger-chip-Serial-Number> --memwr 0x10001080 --val 0xabcd0102
    uint16_t major_value = ((*(uint32_t *)UICR_ADDRESS) & 0xFFFF0000) >> 16;
    uint16_t minor_value = ((*(uint32_t *)UICR_ADDRESS) & 0x0000FFFF);

    uint8_t index = MAJ_VAL_OFFSET_IN_BEACON_INFO;

    m_beacon_info[index++] = MSB_16(major_value);
    m_beacon_info[index++] = LSB_16(major_value);

    m_beacon_info[index++] = MSB_16(minor_value);
    m_beacon_info[index++] = LSB_16(minor_value);
#endif
		m_beacon_info [18]= (NRF_FICR->DEVICEID[1])>>8;
		m_beacon_info [19]= (NRF_FICR->DEVICEID[1])&0xff;
		m_beacon_info [20]= (NRF_FICR->DEVICEID[0])&0xff;
    manuf_specific_data.data.p_data = (uint8_t *) m_beacon_info;
    manuf_specific_data.data.size   = APP_BEACON_INFO_LENGTH;

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

    advdata.name_type             = BLE_ADVDATA_NO_NAME;
    advdata.flags                 = flags;
    advdata.p_manuf_specific_data = &manuf_specific_data;

    err_code = ble_advdata_set(&advdata, NULL);
    APP_ERROR_CHECK(err_code);

    // Initialize advertising parameters (used when starting advertising).
    memset(&m_adv_params, 0, sizeof(m_adv_params));

    m_adv_params.type        = BLE_GAP_ADV_TYPE_ADV_NONCONN_IND;
    m_adv_params.p_peer_addr = NULL;                             // Undirected advertisement.
    m_adv_params.fp          = BLE_GAP_ADV_FP_ANY;
    //m_adv_params.interval    = NON_CONNECTABLE_ADV_INTERVAL;
		m_adv_params.interval = adv_interval;
    m_adv_params.timeout     = APP_CFG_NON_CONN_ADV_TIMEOUT;
}


m_beacon_info [20]= 0xC1; //Here we are changing the top byte of minor ID 
advertising_init();