ESP32学习笔记（28）——BLE GAP从机端广播自定义数据

作者: Leung_ManWah | 来源:发表于2021-07-05 17:57 被阅读0次

一、背景

1.1 低功耗蓝牙（BLE）协议栈

链路层（LL） 控制设备的射频状态，有五个设备状态：待机、广播、扫描、初始化和连接。

广播为广播数据包，而扫描则是监听广播。

GAP通信中角色，中心设备（Central - 主机） 用来扫描和连接 外围设备（Peripheral - 从机）。

大部分情况下外围设备通过广播自己来让中心设备发现自己，并建立 GATT 连接，从而进行更多的数据交换。

也有些情况是不需要连接的，只要外设广播自己的数据即可，用这种方式主要目的是让外围设备，把自己的信息发送给多个中心设备。

1.2 从机广播

从机（外围设备）要被主机连接，那么它就必须先被主机发现。这个时候，从机设备把自身信息以广播形式发射出去。

比如设备A需要先进行广播，即 设备A（Advertiser） 不断发送如下广播信号，t 为广播间隔。每发送一次广播包，我们称其为一次 广播事件（advertising event），因此 t 也称为广播事件间隔，如下图所示。广播事件是一阵一阵的，每次会是有一个持续时间的，蓝牙芯片只有在广播事件期间才打开射频模块发射广播，这个时候功耗比较高，其余时间蓝牙芯片都处于idle待机状态，因此平均功耗就非常低。

当广播发出的时候，每一个广播事件包含三个广播包，即分别在 37/38/39 三个通道上同时广播相同的信息。下图 observer 为主机观察者，advertiser 就是从机广播。

1.3 ESP32蓝牙应用结构

蓝牙是⼀种短距通信系统，其关键特性包括鲁棒性、低功耗、低成本等。蓝牙系统分为两种不同的技术：经典蓝牙 (Classic Bluetooth) 和蓝牙低功耗 (Bluetooth Low Energy)。
ESP32 支持双模蓝牙，即同时支持经典蓝牙和蓝牙低功耗。

从整体结构上，蓝牙可分为控制器 (Controller) 和主机 (Host) 两⼤部分：控制器包括了 PHY、Baseband、Link Controller、Link Manager、Device Manager、HCI 等模块，用于硬件接⼝管理、链路管理等等；主机则包括了 L2CAP、SMP、SDP、ATT、GATT、GAP 以及各种规范，构建了向应用层提供接口的基础，方便应用层对蓝牙系统的访问。主机可以与控制器运行在同⼀个宿主上，也可以分布在不同的宿主上。ESP32 可以支持上述两种方式。

1.4 Bluedroid主机架构

在 ESP-IDF 中，使用经过大量修改后的 BLUEDROID 作为蓝牙主机 (Classic BT + BLE)。BLUEDROID 拥有较为完善的功能，⽀持常用的规范和架构设计，同时也较为复杂。经过大量修改后，BLUEDROID 保留了大多数 BTA 层以下的代码，几乎完全删去了 BTIF 层的代码，使用了较为精简的 BTC 层作为内置规范及 Misc 控制层。修改后的 BLUEDROID 及其与控制器之间的关系如下图：

本篇是关于广播自定义数据包，配置以及启动或关闭广播的流程查看 ESP32学习笔记（26）——BLE GAP从机端广播

二、广播内容参数

在 esp_gap_ble_api_.h 文件中，提供了广播的初始化参数结构体。

/// Advertising data content, according to "Supplement to the Bluetooth Core Specification"
typedef struct {
    bool                    set_scan_rsp;           /*!< Set this advertising data as scan response or not*/
    bool                    include_name;           /*!< Advertising data include device name or not */
    bool                    include_txpower;        /*!< Advertising data include TX power */
    int                     min_interval;           /*!< Advertising data show slave preferred connection min interval.
                                                    The connection interval in the following manner:
                                                    connIntervalmin = Conn_Interval_Min * 1.25 ms
                                                    Conn_Interval_Min range: 0x0006 to 0x0C80
                                                    Value of 0xFFFF indicates no specific minimum.
                                                    Values not defined above are reserved for future use.*/

    int                     max_interval;           /*!< Advertising data show slave preferred connection max interval.
                                                    The connection interval in the following manner:
                                                    connIntervalmax = Conn_Interval_Max * 1.25 ms
                                                    Conn_Interval_Max range: 0x0006 to 0x0C80
                                                    Conn_Interval_Max shall be equal to or greater than the Conn_Interval_Min.
                                                    Value of 0xFFFF indicates no specific maximum.
                                                    Values not defined above are reserved for future use.*/

    int                     appearance;             /*!< External appearance of device */
    uint16_t                manufacturer_len;       /*!< Manufacturer data length */
    uint8_t                 *p_manufacturer_data;   /*!< Manufacturer data point */
    uint16_t                service_data_len;       /*!< Service data length */
    uint8_t                 *p_service_data;        /*!< Service data point */
    uint16_t                service_uuid_len;       /*!< Service uuid length */
    uint8_t                 *p_service_uuid;        /*!< Service uuid array point */
    uint8_t                 flag;                   /*!< Advertising flag of discovery mode, see BLE_ADV_DATA_FLAG detail */
} esp_ble_adv_data_t;

set_scan_rsp：设置此结构体数据是否为扫描响应包
include_name：包含设备名称
include_txpower：包含TX电平发送功率
min_interval：最小广播间隔
max_interval：最大广播间隔
appearance：展示图标
manufacturer_len：制造商特定的数据长度（自定义广播数据长度）
p_manufacturer_data：制造商特定的数据（自定义广播数据）
service_data_len：服务数据长度
p_service_data：服务数据
service_uuid_len：服务UUID长度
p_service_uuid：服务UUID
flags：广播数据标识字段

三、广播设备名称

先调用 esp_ble_gap_set_device_name() 设置名称，然后调用 esp_ble_gap_config_adv_data()，再调用 esp_ble_gap_start_advertising()

static esp_ble_adv_params_t ble_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,
};

static esp_ble_adv_data_t adv_data = {
    .include_name = true,
    .flag = (ESP_BLE_ADV_FLAG_GEN_DISC | ESP_BLE_ADV_FLAG_BREDR_NOT_SPT),
};

esp_ble_gap_set_device_name("hello");  // 设置设备名称
esp_ble_gap_config_adv_data(&adv_data);  // 配置广播内容
esp_ble_gap_start_advertising(&ble_adv_params);  // 开启广播

四、广播展示图标

设置结构体 esp_ble_adv_data_t 中 appearance 的值，图标值如下：

#define ESP_BLE_APPEARANCE_UNKNOWN                 0x0000 /* relate to BTM_BLE_APPEARANCE_UNKNOWN in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_PHONE           0x0040 /* relate to BTM_BLE_APPEARANCE_GENERIC_PHONE in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_COMPUTER        0x0080 /* relate to BTM_BLE_APPEARANCE_GENERIC_COMPUTER in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_WATCH           0x00C0 /* relate to BTM_BLE_APPEARANCE_GENERIC_WATCH in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_SPORTS_WATCH            0x00C1 /* relate to BTM_BLE_APPEARANCE_SPORTS_WATCH in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_CLOCK           0x0100 /* relate to BTM_BLE_APPEARANCE_GENERIC_CLOCK in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_DISPLAY         0x0140 /* relate to BTM_BLE_APPEARANCE_GENERIC_DISPLAY in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_REMOTE          0x0180 /* relate to BTM_BLE_APPEARANCE_GENERIC_REMOTE in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_EYEGLASSES      0x01C0 /* relate to BTM_BLE_APPEARANCE_GENERIC_EYEGLASSES in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_TAG             0x0200 /* relate to BTM_BLE_APPEARANCE_GENERIC_TAG in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_KEYRING         0x0240 /* relate to BTM_BLE_APPEARANCE_GENERIC_KEYRING in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_MEDIA_PLAYER    0x0280 /* relate to BTM_BLE_APPEARANCE_GENERIC_MEDIA_PLAYER in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_BARCODE_SCANNER 0x02C0 /* relate to BTM_BLE_APPEARANCE_GENERIC_BARCODE_SCANNER in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_THERMOMETER     0x0300 /* relate to BTM_BLE_APPEARANCE_GENERIC_THERMOMETER in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_THERMOMETER_EAR         0x0301 /* relate to BTM_BLE_APPEARANCE_THERMOMETER_EAR in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_HEART_RATE      0x0340 /* relate to BTM_BLE_APPEARANCE_GENERIC_HEART_RATE in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_HEART_RATE_BELT         0x0341 /* relate to BTM_BLE_APPEARANCE_HEART_RATE_BELT in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_BLOOD_PRESSURE  0x0380 /* relate to BTM_BLE_APPEARANCE_GENERIC_BLOOD_PRESSURE in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_BLOOD_PRESSURE_ARM      0x0381 /* relate to BTM_BLE_APPEARANCE_BLOOD_PRESSURE_ARM in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_BLOOD_PRESSURE_WRIST    0x0382 /* relate to BTM_BLE_APPEARANCE_BLOOD_PRESSURE_WRIST in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_HID             0x03C0 /* relate to BTM_BLE_APPEARANCE_GENERIC_HID in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_HID_KEYBOARD            0x03C1 /* relate to BTM_BLE_APPEARANCE_HID_KEYBOARD in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_HID_MOUSE               0x03C2 /* relate to BTM_BLE_APPEARANCE_HID_MOUSE in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_HID_JOYSTICK            0x03C3 /* relate to BTM_BLE_APPEARANCE_HID_JOYSTICK in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_HID_GAMEPAD             0x03C4 /* relate to BTM_BLE_APPEARANCE_HID_GAMEPAD in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_HID_DIGITIZER_TABLET    0x03C5 /* relate to BTM_BLE_APPEARANCE_HID_DIGITIZER_TABLET in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_HID_CARD_READER         0x03C6 /* relate to BTM_BLE_APPEARANCE_HID_CARD_READER in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_HID_DIGITAL_PEN         0x03C7 /* relate to BTM_BLE_APPEARANCE_HID_DIGITAL_PEN in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_HID_BARCODE_SCANNER     0x03C8 /* relate to BTM_BLE_APPEARANCE_HID_BARCODE_SCANNER in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_GLUCOSE         0x0400 /* relate to BTM_BLE_APPEARANCE_GENERIC_GLUCOSE in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_WALKING         0x0440 /* relate to BTM_BLE_APPEARANCE_GENERIC_WALKING in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_WALKING_IN_SHOE         0x0441 /* relate to BTM_BLE_APPEARANCE_WALKING_IN_SHOE in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_WALKING_ON_SHOE         0x0442 /* relate to BTM_BLE_APPEARANCE_WALKING_ON_SHOE in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_WALKING_ON_HIP          0x0443 /* relate to BTM_BLE_APPEARANCE_WALKING_ON_HIP in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_CYCLING         0x0480 /* relate to BTM_BLE_APPEARANCE_GENERIC_CYCLING in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_CYCLING_COMPUTER        0x0481 /* relate to BTM_BLE_APPEARANCE_CYCLING_COMPUTER in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_CYCLING_SPEED           0x0482 /* relate to BTM_BLE_APPEARANCE_CYCLING_SPEED in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_CYCLING_CADENCE         0x0483 /* relate to BTM_BLE_APPEARANCE_CYCLING_CADENCE in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_CYCLING_POWER           0x0484 /* relate to BTM_BLE_APPEARANCE_CYCLING_POWER in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_CYCLING_SPEED_CADENCE   0x0485 /* relate to BTM_BLE_APPEARANCE_CYCLING_SPEED_CADENCE in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_PULSE_OXIMETER  0x0C40 /* relate to BTM_BLE_APPEARANCE_GENERIC_PULSE_OXIMETER in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_PULSE_OXIMETER_FINGERTIP 0x0C41 /* relate to BTM_BLE_APPEARANCE_PULSE_OXIMETER_FINGERTIP in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_PULSE_OXIMETER_WRIST    0x0C42 /* relate to BTM_BLE_APPEARANCE_PULSE_OXIMETER_WRIST in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_WEIGHT          0x0C80 /* relate to BTM_BLE_APPEARANCE_GENERIC_WEIGHT in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_PERSONAL_MOBILITY_DEVICE    0x0CC0 /* relate to BTM_BLE_APPEARANCE_GENERIC_PERSONAL_MOBILITY_DEVICE in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_POWERED_WHEELCHAIR                  0x0CC1 /* relate to BTM_BLE_APPEARANCE_POWERED_WHEELCHAIR in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_MOBILITY_SCOOTER                    0x0CC2 /* relate to BTM_BLE_APPEARANCE_MOBILITY_SCOOTER in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_CONTINUOUS_GLUCOSE_MONITOR  0x0D00 /* relate to BTM_BLE_APPEARANCE_GENERIC_CONTINUOUS_GLUCOSE_MONITOR in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_INSULIN_PUMP                0x0D40 /* relate to BTM_BLE_APPEARANCE_GENERIC_INSULIN_PUMP in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_INSULIN_PUMP_DURABLE_PUMP           0x0D41 /* relate to BTM_BLE_APPEARANCE_INSULIN_PUMP_DURABLE_PUMP in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_INSULIN_PUMP_PATCH_PUMP             0x0D44 /* relate to BTM_BLE_APPEARANCE_INSULIN_PUMP_PATCH_PUMP in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_INSULIN_PEN                         0x0D48 /* relate to BTM_BLE_APPEARANCE_INSULIN_PEN in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_MEDICATION_DELIVERY         0x0D80 /* relate to BTM_BLE_APPEARANCE_GENERIC_MEDICATION_DELIVERY in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_GENERIC_OUTDOOR_SPORTS  0x1440             /* relate to BTM_BLE_APPEARANCE_GENERIC_OUTDOOR_SPORTS in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_OUTDOOR_SPORTS_LOCATION 0x1441             /* relate to BTM_BLE_APPEARANCE_OUTDOOR_SPORTS_LOCATION in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_OUTDOOR_SPORTS_LOCATION_AND_NAV     0x1442 /* relate to BTM_BLE_APPEARANCE_OUTDOOR_SPORTS_LOCATION_AND_NAV in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_OUTDOOR_SPORTS_LOCATION_POD         0x1443 /* relate to BTM_BLE_APPEARANCE_OUTDOOR_SPORTS_LOCATION_POD in stack/btm_ble_api.h */
#define ESP_BLE_APPEARANCE_OUTDOOR_SPORTS_LOCATION_POD_AND_NAV 0x1444 /* relate to BTM_BLE_APPEARANCE_OUTDOOR_SPORTS_LOCATION_POD_AND_NAV in stack/btm_ble_api.h */

先设置 appearance 的值，然后调用 esp_ble_gap_config_adv_data()，再调用 esp_ble_gap_start_advertising()

static esp_ble_adv_params_t ble_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,
};

static esp_ble_adv_data_t adv_data = {
    .appearance = ESP_BLE_APPEARANCE_GENERIC_PHONE,
    .flag = (ESP_BLE_ADV_FLAG_GEN_DISC | ESP_BLE_ADV_FLAG_BREDR_NOT_SPT),
};

esp_ble_gap_config_adv_data(&adv_data);  // 配置广播内容
esp_ble_gap_start_advertising(&ble_adv_params);  // 开启广播

五、广播UUID的值

UUID的种类分为两种：

一种是 SIG 定义的公共服务 UUID，所有的公共服务共用一个 128bit 的基础 UUID，不同的服务采用一个 16bit UUID 进行定义。基础UUID：0x0000xxxx-0000-1000-8000-00805F9B34FB
另一种就是私有服务的 UUID，这是一个自定义的 128bit UUID。

注意：广播包里的 UUID 不影响服务特征值中 UUID 的值，仅仅是让广播把 UUID 的值广播给扫描设备，方便观察。

这里广播了两个 16bite UUID：0x00EE、0x00FF
调用 esp_ble_gap_config_adv_data()，再调用 esp_ble_gap_start_advertising()

static uint8_t adv_service_uuid128[32] = {
    /* LSB <--------------------------------------------------------------------------------> MSB */
    //first uuid, 16bit, [12],[13] is the value
    0xfb, 0x34, 0x9b, 0x5f, 0x80, 0x00, 0x00, 0x80, 0x00, 0x10, 0x00, 0x00, 0xEE, 0x00, 0x00, 0x00,
    //second uuid, 32bit, [12], [13], [14], [15] is the value
    0xfb, 0x34, 0x9b, 0x5f, 0x80, 0x00, 0x00, 0x80, 0x00, 0x10, 0x00, 0x00, 0xFF, 0x00, 0x00, 0x00,
};

static esp_ble_adv_params_t ble_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,
};

static esp_ble_adv_data_t adv_data = {
    .service_uuid_len = sizeof(adv_service_uuid128),
    .p_service_uuid = adv_service_uuid128,
    .flag = (ESP_BLE_ADV_FLAG_GEN_DISC | ESP_BLE_ADV_FLAG_BREDR_NOT_SPT),
};

esp_ble_gap_config_adv_data(&adv_data);  // 配置广播内容
esp_ble_gap_start_advertising(&ble_adv_params);  // 开启广播

六、广播从机的连接间隔参数

从机与主机之间的连接间隔，是由从机提出与主机进行协商，然后再由主机决定的参数。

先设置 min_interval 和 max_interval 的值，然后调用 esp_ble_gap_config_adv_data()，再调用 esp_ble_gap_start_advertising()

static esp_ble_adv_params_t ble_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,
};

static esp_ble_adv_data_t adv_data = {
    .min_interval = 0x000A, //slave connection min interval, Time = min_interval * 1.25 msec=7.5ms
    .max_interval = 0x0014, //slave connection max interval, Time = max_interval * 1.25 msec=20ms
    .flag = (ESP_BLE_ADV_FLAG_GEN_DISC | ESP_BLE_ADV_FLAG_BREDR_NOT_SPT),
};

esp_ble_gap_config_adv_data(&adv_data);  // 配置广播内容
esp_ble_gap_start_advertising(&ble_adv_params);  // 开启广播

通过手机APP nrf connect 扫描后显示：

七、广播自定义数据

p_manufacturer_data：制造商自定义的数据，这个参数可以自由的设置，只要广播包的空间足够。假设自定义数据为 0x11，0x22，0x33，0x44，0x55。

static uint8_t user_data[5] = {0x11, 0x22, 0x33, 0x44, 0x55};

static esp_ble_adv_params_t ble_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,
};

static esp_ble_adv_data_t adv_data = {
    .manufacturer_len = sizeof(user_data),
    .p_manufacturer_data = user_data,
    .flag = (ESP_BLE_ADV_FLAG_GEN_DISC | ESP_BLE_ADV_FLAG_BREDR_NOT_SPT),
};

esp_ble_gap_config_adv_data(&adv_data);  // 配置广播内容
esp_ble_gap_start_advertising(&ble_adv_params);  // 开启广播

八、广播扫描响应包

先设置 set_scan_rsp = true 将此包设为扫描响应包，然后调用 esp_ble_gap_config_adv_data()，再调用 esp_ble_gap_start_advertising()

static uint8_t user_data[3] = {0x11, 0x22, 0x33};
static uint8_t user_data2[3] = {0x66, 0x77, 0x88};

static esp_ble_adv_params_t ble_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,
};

static esp_ble_adv_data_t srsp_data = {
    .set_scan_rsp = true,
    .manufacturer_len = sizeof(user_data2),
    .p_manufacturer_data = user_data2,
};

static esp_ble_adv_data_t adv_data = {
    .manufacturer_len = sizeof(user_data),
    .p_manufacturer_data = user_data,
    .flag = (ESP_BLE_ADV_FLAG_GEN_DISC | ESP_BLE_ADV_FLAG_BREDR_NOT_SPT),
};

esp_ble_gap_config_adv_data(&srsp_data);  // 配置扫描响应包
esp_ble_gap_config_adv_data(&adv_data);  // 配置广播数据包
esp_ble_gap_start_advertising(&ble_adv_params);  // 开启广播

九、实例

根据 esp-idf\examples\bluetooth\bluedroid\ble\ble_ibeacon 中的例程修改

#include <stdint.h>
#include <string.h>
#include <stdbool.h>
#include <stdio.h>
#include "nvs_flash.h"

#include "esp_bt.h"
#include "esp_gap_ble_api.h"
#include "esp_gattc_api.h"
#include "esp_gatt_defs.h"
#include "esp_bt_main.h"
#include "esp_bt_defs.h"
#include "esp_ibeacon_api.h"
#include "esp_log.h"
#include "freertos/FreeRTOS.h"

static const char* DEMO_TAG = "IBEACON_DEMO";

///Declare static functions
static void esp_gap_cb(esp_gap_ble_cb_event_t event, esp_ble_gap_cb_param_t *param);

static esp_ble_adv_params_t ble_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,
};

static uint8_t adv_service_uuid128[32] = {
    /* LSB <--------------------------------------------------------------------------------> MSB */
    //first uuid, 16bit, [12],[13] is the value
    0xfb, 0x34, 0x9b, 0x5f, 0x80, 0x00, 0x00, 0x80, 0x00, 0x10, 0x00, 0x00, 0xEE, 0x00, 0x00, 0x00,
    //second uuid, 32bit, [12], [13], [14], [15] is the value
    0xfb, 0x34, 0x9b, 0x5f, 0x80, 0x00, 0x00, 0x80, 0x00, 0x10, 0x00, 0x00, 0xFF, 0x00, 0x00, 0x00,
};

static uint8_t user_data[3] = {0x11, 0x22, 0x33};
static uint8_t user_data2[3] = {0x66, 0x77, 0x88};

static esp_ble_adv_data_t srsp_data = {
    .set_scan_rsp = true,
    .manufacturer_len = sizeof(user_data2),
    .p_manufacturer_data = user_data2,
};

static esp_ble_adv_data_t adv_data = {
    .set_scan_rsp = false,
    .include_name = true,
    .min_interval = 0x000A, //slave connection min interval, Time = min_interval * 1.25 msec=7.5ms
    .max_interval = 0x0014, //slave connection max interval, Time = max_interval * 1.25 msec=20ms
    .appearance = ESP_BLE_APPEARANCE_GENERIC_PHONE,
    .manufacturer_len = sizeof(user_data),
    .p_manufacturer_data = user_data,
    .service_uuid_len = sizeof(adv_service_uuid128),
    .p_service_uuid = adv_service_uuid128,
    .flag = (ESP_BLE_ADV_FLAG_GEN_DISC | ESP_BLE_ADV_FLAG_BREDR_NOT_SPT),
};
        
static void esp_gap_cb(esp_gap_ble_cb_event_t event, esp_ble_gap_cb_param_t *param)
{
    esp_err_t err;

    switch (event) {
    case ESP_GAP_BLE_ADV_DATA_SET_COMPLETE_EVT:{
        esp_ble_gap_start_advertising(&ble_adv_params);
        break;
    }

    case ESP_GAP_BLE_ADV_START_COMPLETE_EVT:
        //adv start complete event to indicate adv start successfully or failed
        if ((err = param->adv_start_cmpl.status) != ESP_BT_STATUS_SUCCESS) {
            ESP_LOGE(DEMO_TAG, "Adv start failed: %s", esp_err_to_name(err));
        }
        break;

    case ESP_GAP_BLE_ADV_STOP_COMPLETE_EVT:
        if ((err = param->adv_stop_cmpl.status) != ESP_BT_STATUS_SUCCESS){
            ESP_LOGE(DEMO_TAG, "Adv stop failed: %s", esp_err_to_name(err));
        }
        else {
            ESP_LOGI(DEMO_TAG, "Stop adv successfully");
        }
        break;

    default:
        break;
    }
}


void ble_ibeacon_appRegister(void)
{
    esp_err_t status;

    ESP_LOGI(DEMO_TAG, "register callback");

    //register the scan callback function to the gap module
    if ((status = esp_ble_gap_register_callback(esp_gap_cb)) != ESP_OK) {
        ESP_LOGE(DEMO_TAG, "gap register error: %s", esp_err_to_name(status));
        return;
    }

}

void ble_ibeacon_init(void)
{
    esp_bluedroid_init();
    esp_bluedroid_enable();
    ble_ibeacon_appRegister();
}

void app_main(void)
{
    ESP_ERROR_CHECK(nvs_flash_init());
    ESP_ERROR_CHECK(esp_bt_controller_mem_release(ESP_BT_MODE_CLASSIC_BT));
    esp_bt_controller_config_t bt_cfg = BT_CONTROLLER_INIT_CONFIG_DEFAULT();
    esp_bt_controller_init(&bt_cfg);
    esp_bt_controller_enable(ESP_BT_MODE_BLE);

    ble_ibeacon_init();

    esp_ble_gap_set_device_name("hello");
    esp_ble_gap_config_adv_data(&srsp_data);
    esp_ble_gap_config_adv_data(&adv_data);
}

• 由 Leung 写于 2021 年 7 月 5 日