Renaming connected device

[Thomas U]

Hello Nordic

I am developing a sensor application using nRF52833. The user must be able to connect to the nRF52833 and give it a new name. I have a name characteristic that the user will write the new name to. When the nRF52833 receives the new name, it should disconnect and start advertising the new name. Then the user will reconnect using the new name.

I have read a lot of post on this subject. But none of them seems to work for me. I get the general idea about how to do it:

• Set the new name using sd_ble_gap_device_name_set
• Restart the advertising, several ways to do it are described in posts

I am using: SDK 17.1.0

Code starting point: examples\ble_peripheral\ble_app_template

I can rename the nRF52833, but nothing happens until a power cycling takes place.

This is my code:

In the main file I check whether the user has requested a new name. Then I set the new name and run the advertisement initialization again (suggested in this forum)

 if (is_new_device_name_requested()) // if the user has requested a new name for this sensor, then go ahead and set it

    {

        NRF_LOG_INFO("setting new device name");

        set_device_name(DEVICE_NAME);

        advertising_init();

  }

The set_device_name function is shown below:

void set_device_name(uint8_t* first_name)
{
ret_code_t err_code;
ble_gap_conn_sec_mode_t sec_mode;

BLE_GAP_CONN_SEC_MODE_SET_OPEN(&sec_mode);

memset(full_device_name, 0, sizeof full_device_name);
strcpy(full_device_name, first_name);
strcat(full_device_name, general_par.last_device_name);

err_code = sd_ble_gap_device_name_set(&sec_mode,
(const uint8_t *)full_device_name,
strlen(full_device_name));
APP_ERROR_CHECK(err_code);
general_par.is_new_device_name_wanted = false;
}

The advertising_init function is shown below:

static void advertising_init(void)
{
ret_code_t err_code;
ble_advertising_init_t init;

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

init.advdata.name_type = BLE_ADVDATA_FULL_NAME;
init.advdata.include_appearance = true;
init.advdata.flags = BLE_GAP_ADV_FLAGS_LE_ONLY_GENERAL_DISC_MODE;
init.advdata.uuids_complete.uuid_cnt = sizeof(m_adv_uuids) / sizeof(m_adv_uuids[0]);
init.advdata.uuids_complete.p_uuids = m_adv_uuids;

init.config.ble_adv_fast_enabled = true;
init.config.ble_adv_fast_interval = APP_ADV_INTERVAL;
init.config.ble_adv_fast_timeout = APP_ADV_DURATION;

init.evt_handler = on_adv_evt;

err_code = ble_advertising_init(&m_advertising, &init);
APP_ERROR_CHECK(err_code);

ble_advertising_conn_cfg_tag_set(&m_advertising, APP_BLE_CONN_CFG_TAG);
}

[Thomas U]

Hi Hieu, I really appreciate your help. Nice discovery that "ble_advertising_start()" is called by the module itself. The error that I received must be generated by calling "ble_advertising_start()" two times. When I delete the call to "ble_advertising_start()", there is no error, but the NRF52833 goes into a silent disconnected state without advertising. That is, if I do not change the device name, then the advertising works fine, but after a device name change and a disconnect the silent state occurs. 

 

I am using DFU and setting a breakpoint is not so easy. But searching this forum I see that it is possible.

 

I am at a small Christmas vacation right now. I will be back in the office Tuesday. Then I can set breakpoints and continue solving this mystery

[Hieu]

I don't think you need to worry about the DFU. Just supporting DFU is not going to cause problems with using breakpoints. It is the SoftDevice and its radio operations that don't like breakpoints, and breakpoint throws their timing off and break communications. Therefore, you won't be able to resume from a breakpoint. We will use it as a tool to see how far the code go and what functions/branches got executed.

We will resume when you get back though. Enjoy your vacation! 

[Thomas U]

Hello Hieu

I am back and ready to tackle this issue

The error was caused by calling "ble_advertising_start()" twice. Now there is no errors.

After renaming device and a disconnect, the NRF52833 starts advertising again but it has lost its name. By using the nRF connect tool i see an advertisement from my NRF52833. I recognize the address: DE:A0:BB:0F:EF:9D. But the name is <Unknown name>

[Hieu]

Hello Thomas,

Sorry for the late follow up. How is your new_advdata setup? Does it already include the full device name field?

[Thomas U]

Hello Hieu

Thank you very much, I am so happy, finally it works.

Setting the full device name did the trick

static void adv_data_update(void)
{
    ret_code_t                  err_code;

    NRF_LOG_INFO("Updating advertising data!");
    
    new_advdata.name_type = BLE_ADVDATA_FULL_NAME;
    err_code = ble_advertising_advdata_update(&m_advertising, &new_advdata, NULL);
    APP_ERROR_CHECK(err_code);  
    
    NRF_LOG_INFO("Advertising data updated!");
}