ESP32 Forum

Hi,
I'm trying to use ESP32 BLE GATT server code to advertise a data with my specific manufacture data. So I need to update manufacture data every seconds using a timer.

This is my manuafacture data looks like.
uint8_t advtimer_value = 0x22;
"uint8_t manufacture_specific_data[8] = {0x0b, advtimer_value, 0x02, 0x00};"
Till her it works and if i change the value in between then iam not able to update this advtimer_value in esp32. It says not a const . How should overcome this. Or is there any other way which i can achieve my goal.
Please help.

chegewara wrote: ↑

Tue May 19, 2020 4:15 am

Code: Select all

uint8_t advtimer_value = 0x22;
uint8_t manufacture_specific_data[8] = {0x0b, 0x0, 0x02, 0x00};
manufacture_specific_data[1] = advtimer_value;

Hi , do i need to do anything on the below functions to get the changes reflected in my advertising frames.
case ESP_GAP_BLE_ADV_DATA_SET_COMPLETE_EVT:
adv_config_done &= (~ADV_CONFIG_FLAG);
manufacture_specific_data[1] = advtimer_value;
if (adv_config_done == 0)
{
esp_ble_gap_start_advertising(&adv_params);
}
break;
case ESP_GAP_BLE_SCAN_RSP_DATA_SET_COMPLETE_EVT:
adv_config_done &= (~SCAN_RSP_CONFIG_FLAG);
if (adv_config_done == 0)
{
esp_ble_gap_start_advertising(&adv_params);
}
break;

And my "advtimer_value" will be inside a timer, so do i just need to change the value there or do i need to make any changes in the BLE code.

chegewara wrote: ↑

Tue May 19, 2020 4:15 am

Code: Select all

uint8_t advtimer_value = 0x22;
uint8_t manufacture_specific_data[8] = {0x0b, 0x0, 0x02, 0x00};
manufacture_specific_data[1] = advtimer_value;

Hi thanks for the quick reply,

Do i need to make any changes in the belwo functions to reflect the changes in my advertsing frames,

case ESP_GAP_BLE_ADV_DATA_SET_COMPLETE_EVT:
adv_config_done &= (~ADV_CONFIG_FLAG);
manufacture_specific_data[1] = advtimer_value;
if (adv_config_done == 0)
{
esp_ble_gap_start_advertising(&adv_params);
}
break;
case ESP_GAP_BLE_SCAN_RSP_DATA_SET_COMPLETE_EVT:
adv_config_done &= (~SCAN_RSP_CONFIG_FLAG);
if (adv_config_done == 0)
{
esp_ble_gap_start_advertising(&adv_params);
}
break;

My "advtimer_value" will be updated inside a timer functions, so do i just neeed to update the advtimer_value value ther or do i need to make any changes in the BLE functions.

When advtimer_val is updated somewhere else, then you have to stop advertising, update manufacturer data and start advertising again.

hi , thanks for your response.

uint8_t manufacture_specific_data[4] = {0x0b, 0xFF, 0x02, 0x00};

// scan response data
static esp_ble_adv_data_t scan_rsp_data = {
.set_scan_rsp = true,
.include_name = true,
.include_txpower = false,
.min_interval = 0x0006,
.max_interval = 0x0010,
.appearance = 0x00,
.manufacturer_len = sizeof(manufacture_specific_data),
.p_manufacturer_data = manufacture_specific_data,
.service_data_len = 0,
.p_service_data = NULL,
.service_uuid_len = ESP_UUID_LEN_128,
.p_service_uuid = service_uuid,
.flag = (ESP_BLE_ADV_FLAG_GEN_DISC | ESP_BLE_ADV_FLAG_BREDR_NOT_SPT),
};

I want to change the manufacture_specific_data[2]= advtimer_value ;

advtimer_value will be updated every second based on a timer.

But the advertising value is not getting any changes even if the " advtimer_value " in the time is changing every second. every time I change the value I am stopping the advertisement as you said and after changing the value restarting the advertisement.

What I am doing wrong.

I dont have IDF example now, but here is simplest arduino example to show you idea:

Iam using esp gatt server demo code
:https://github.com/espressif/esp-idf/bl ... tts_demo.c


uint8_t manufacture_specific_data[8] = { 0x0b, 0xFF, 0x02, 0x00};
uint8_t checkNum = 0;


/* The length of adv data must be less than 31 bytes */
static esp_ble_adv_data_t adv_data = {
.set_scan_rsp = false,
.include_name = false,
.include_txpower = false,
.min_interval = 0x20,
.max_interval = 0x40, //slave connection max interval, Time = max_interval * 1.25 msec
.appearance = 0x00,
// .manufacturer_len = sizeof(manufacture_specific_data),
// .p_manufacturer_data = &manufacture_specific_data,
.service_data_len = 0,
.p_service_data = NULL,
.service_uuid_len = ESP_UUID_LEN_128,
.p_service_uuid = Huilan_service_uuid,
.flag = (ESP_BLE_ADV_FLAG_GEN_DISC | ESP_BLE_ADV_FLAG_BREDR_NOT_SPT),
};

// scan response data
static esp_ble_adv_data_t scan_rsp_data = {
.set_scan_rsp = true,
.include_name = true,
.include_txpower = false,
.min_interval = 0x0006,
.max_interval = 0x0010,
.appearance = 0x00,
.manufacturer_len = sizeof(manufacture_specific_data),
.p_manufacturer_data = manufacture_specific_data,
.service_data_len = 0,
.p_service_data = NULL,
.service_uuid_len = ESP_UUID_LEN_128,
.p_service_uuid = Huilan_service_uuid,
.flag = (ESP_BLE_ADV_FLAG_GEN_DISC | ESP_BLE_ADV_FLAG_BREDR_NOT_SPT),
};
static esp_ble_adv_params_t adv_params = {
.adv_int_min = 0x20,
.adv_int_max = 0x40,
.adv_type = ADV_TYPE_IND,
.own_addr_type = BLE_ADDR_TYPE_PUBLIC,
.channel_map = ADV_CHNL_ALL,
.adv_filter_policy = ADV_FILTER_ALLOW_SCAN_ANY_CON_ANY,
};



///////////////////////////////////////////////////////////////////////////////////////////////////////
This is the timer call back where I updated the manufacture data

void periodic_timer_callback(void *arg)
{
checkNum++;
int64_t time_since_boot = esp_timer_get_time();
ESP_LOGI(timer_tag, "Periodic timer called, time since boot: %lld us", time_since_boot);
if (checkNum != 250)
{
dyn_adv_update(false);
manufacture_specific_data[2] = checkNum;
dyn_adv_update(true);
}
else
{
ESP_ERROR_CHECK(esp_timer_stop(periodic_timer));
ESP_ERROR_CHECK(esp_timer_delete(periodic_timer));
ESP_LOGI(timer_tag, "Stopped and deleted timers");
}
}

void dyn_adv_update(bool param)
{
if (param == false)
esp_ble_gap_stop_advertising();
if (param == true)
esp_ble_gap_start_advertising(&adv_params);
}


so that each time the periodic timer is called the manufacture data needs to be updated. The timer works fine. But the data is not getting updated when advertising.

Hi ,
I am also trying the same code from esp32 gatt server demo.

is there anything to do with the initialization of manufacture specifi data.

You need to call this function only, and code you already have will take care of rest (will start advertising thru events): https://github.com/espressif/esp-idf/bl ... emo.c#L208
https://github.com/espressif/esp-idf/bl ... emo.c#L202