重要概念
ATT定义了三种类型：
- profile（剖面）
- service（服务）
- characterisic（特征）
三者是依次包含的关系
- profile位于顶层，由若干个Service组成
- profile可以理解为蓝牙协议栈的纵向剖面，包含若干个协议
- 一个service包含若干个characteristic。也可以通过include的方式包含其他service
- 一个characteristic包含一个properties，一个value，一个或多个descriptor
- properties定义value如何使用，以及descriptor如何被访问
- value是characteristic的实际值，即实际数据
- descriptor保存一些与value相关的信息
主要流程如下：
- 由gap回调函数完成扫描和建立连接的过程
- 由gattc回调函数完成数据写入的过程
头文件
/****************************************************************************
*
* This demo showcases BLE GATT client. It can scan BLE devices and connect to one device.
* Run the gatt_server demo, the client demo will automatically connect to the gatt_server demo.
* Client demo will enable gatt_server's notify after connection. The two devices will then exchange
* data.
*
****************************************************************************/
#include <stdint.h>
#include <string.h>
#include <stdbool.h>
#include <stdio.h>
#include "nvs.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_gatt_common_api.h"
#include "esp_log.h"
#include "freertos/FreeRTOS.h"宏定义和静态变量
一个GATT server或GATT client可以同时运行多个application profile。通信时，是application profile一对一的通信。
#define GATTC_TAG "GATTC_DEMO"
#define REMOTE_SERVICE_UUID 0x00FF//远程服务UUID，默认16位（UUID是通用唯一识别码）
#define REMOTE_NOTIFY_CHAR_UUID 0xFF01//远程通知字符UUID
#define PROFILE_NUM 1//profile个数
#define PROFILE_A_APP_ID 0//profile中一个应用的uuid
#define INVALID_HANDLE 0//无效句柄
static const char remote_device_name[] = "ESP_GATTS_DEMO";//远程设备名
static bool connect = false;//是否连接的标志位
static bool get_server = false;//是否得到搜索结果的标志位
static esp_gattc_char_elem_t *char_elem_result = NULL;//特征元素
static esp_gattc_descr_elem_t *descr_elem_result = NULL;//描述符元素函数声明
/* Declare static functions */
/*gap ble回调函数
gap是基础的蓝牙profile，提供蓝牙设备的通用访问功能
*/
static void esp_gap_cb(esp_gap_ble_cb_event_t event, esp_ble_gap_cb_param_t *param);
//gatt client回调函数，gattc_if是gatt client的访问接口，不同profile的gattc_if不同
static void esp_gattc_cb(esp_gattc_cb_event_t event, esp_gatt_if_t gattc_if, esp_ble_gattc_cb_param_t *param);
//gattc profile事件处理函数
static void gattc_profile_event_handler(esp_gattc_cb_event_t event, esp_gatt_if_t gattc_if, esp_ble_gattc_cb_param_t *param);结构体
esp_bt_uuid_t是一个结构体，包括以下成员
- uint16_t len
- UUID长度，有16位、32位和128位
- uint16_t uuid16
- uint32_t uuid32
- uint8_t uuid128[16]
- union esp_bt_uuid_t::[anonymous] uuid
- 就是UUID
//远程服务UUID
static esp_bt_uuid_t remote_filter_service_uuid = {
.len = ESP_UUID_LEN_16,
.uuid = {.uuid16 = REMOTE_SERVICE_UUID,},
};
//远程服务过滤UUID
static esp_bt_uuid_t remote_filter_char_uuid = {
.len = ESP_UUID_LEN_16,
.uuid = {.uuid16 = REMOTE_NOTIFY_CHAR_UUID,},
};
//通知描述符UUID
static esp_bt_uuid_t notify_descr_uuid = {
.len = ESP_UUID_LEN_16,
.uuid = {.uuid16 = ESP_GATT_UUID_CHAR_CLIENT_CONFIG,},
};
//扫描参数
static esp_ble_scan_params_t ble_scan_params = {
.scan_type = BLE_SCAN_TYPE_ACTIVE,
.own_addr_type = BLE_ADDR_TYPE_PUBLIC,
.scan_filter_policy = BLE_SCAN_FILTER_ALLOW_ALL,
.scan_interval = 0x50,
.scan_window = 0x30,
.scan_duplicate = BLE_SCAN_DUPLICATE_DISABLE
};
//gatt client profile实例
struct gattc_profile_inst {
esp_gattc_cb_t gattc_cb;//gattc回调函数
uint16_t gattc_if;//gattc访问接口
uint16_t app_id;//应用ID
uint16_t conn_id;//连接ID
uint16_t service_start_handle;//service开始句柄
uint16_t service_end_handle;//service结束句柄
uint16_t char_handle;//特征句柄
esp_bd_addr_t remote_bda;//远程设备地址（即GATT server）
};
/* One gatt-based profile one app_id and one gattc_if, this array will store the gattc_if returned by ESP_GATTS_REG_EVT */
static struct gattc_profile_inst gl_profile_tab[PROFILE_NUM] = {
[PROFILE_A_APP_ID] = {
.gattc_cb = gattc_profile_event_handler,
.gattc_if = ESP_GATT_IF_NONE, /* Not get the gatt_if, so initial is ESP_GATT_IF_NONE */
},
};profile事件处理函数
作用如下：
- GATTC client注册完成后设置扫描参数
- 建立起物理连接后保存连接ID和远程设备地址，并配置MTU
- 建立起虚拟连接后打印状态
- 发现服务完成后搜索指定服务
- 拿到搜索结果后保存指定服务的开始句柄和结束句柄
- 搜索完成后获取其中的characteristic，并为此服务注册通知
- 通知注册完成后获取服务的描述符，并向其中写入数据
- 描述符写入完成后，写入特征的值
形参有三个：
- event 事件名
- gattc_if gattc访问接口
- param gattc回调参数
static void gattc_profile_event_handler(esp_gattc_cb_event_t event, esp_gatt_if_t gattc_if, esp_ble_gattc_cb_param_t *param)
{
esp_ble_gattc_cb_param_t *p_data = (esp_ble_gattc_cb_param_t *)param;
switch (event) {
case ESP_GATTC_REG_EVT://当GATT client注册时
ESP_LOGI(GATTC_TAG, "REG_EVT");
esp_err_t scan_ret = esp_ble_gap_set_scan_params(&ble_scan_params);//设置扫描参数
if (scan_ret){
ESP_LOGE(GATTC_TAG, "set scan params error, error code = %x", scan_ret);
}
break;
case ESP_GATTC_CONNECT_EVT:{//当建立起BLE物理连接时
ESP_LOGI(GATTC_TAG, "ESP_GATTC_CONNECT_EVT conn_id %d, if %d", p_data->connect.conn_id, gattc_if);
//将连接ID和设备地址存储数组
gl_profile_tab[PROFILE_A_APP_ID].conn_id = p_data->connect.conn_id;
memcpy(gl_profile_tab[PROFILE_A_APP_ID].remote_bda, p_data->connect.remote_bda, sizeof(esp_bd_addr_t));
//以16进制打印设备地址
ESP_LOGI(GATTC_TAG, "REMOTE BDA:");
esp_log_buffer_hex(GATTC_TAG, gl_profile_tab[PROFILE_A_APP_ID].remote_bda, sizeof(esp_bd_addr_t));
//配置MTU（最大传输单元）大小，一次连接只能调用一次
//调用前可使用esp_ble_gatt_set_local_mtu()配置本地MTU大小
esp_err_t mtu_ret = esp_ble_gattc_send_mtu_req (gattc_if, p_data->connect.conn_id);
if (mtu_ret){
ESP_LOGE(GATTC_TAG, "config MTU error, error code = %x", mtu_ret);
}
break;
}
case ESP_GATTC_OPEN_EVT://当GATT虚拟连接建立时
//打印打开状态
if (param->open.status != ESP_GATT_OK){
ESP_LOGE(GATTC_TAG, "open failed, status %d", p_data->open.status);
break;
}
ESP_LOGI(GATTC_TAG, "open success");
break;
case ESP_GATTC_DIS_SRVC_CMPL_EVT://当BLE发现服务完成时
//如果发现服务失败，则打印相关信息
if (param->dis_srvc_cmpl.status != ESP_GATT_OK){
ESP_LOGE(GATTC_TAG, "discover service failed, status %d", param->dis_srvc_cmpl.status);
break;
}
ESP_LOGI(GATTC_TAG, "discover service complete conn_id %d", param->dis_srvc_cmpl.conn_id);
//搜索service，并伴随一个service搜索完成事件
esp_ble_gattc_search_service(gattc_if, param->cfg_mtu.conn_id, &remote_filter_service_uuid);
break;
case ESP_GATTC_CFG_MTU_EVT://当MTU配置完成时
if (param->cfg_mtu.status != ESP_GATT_OK){
ESP_LOGE(GATTC_TAG,"config mtu failed, error status = %x", param->cfg_mtu.status);
}
ESP_LOGI(GATTC_TAG, "ESP_GATTC_CFG_MTU_EVT, Status %d, MTU %d, conn_id %d", param->cfg_mtu.status, param->cfg_mtu.mtu, param->cfg_mtu.conn_id);
break;
case ESP_GATTC_SEARCH_RES_EVT: {//当得到搜索结果时
ESP_LOGI(GATTC_TAG, "SEARCH RES: conn_id = %x is primary service %d", p_data->search_res.conn_id, p_data->search_res.is_primary);
ESP_LOGI(GATTC_TAG, "start handle %d end handle %d current handle value %d", p_data->search_res.start_handle, p_data->search_res.end_handle, p_data->search_res.srvc_id.inst_id);
if (p_data->search_res.srvc_id.uuid.len == ESP_UUID_LEN_16 && p_data->search_res.srvc_id.uuid.uuid.uuid16 == REMOTE_SERVICE_UUID) {//若搜索结果uuid长度为16位且地址等于自定义的目标地址
ESP_LOGI(GATTC_TAG, "service found");
get_server = true;
gl_profile_tab[PROFILE_A_APP_ID].service_start_handle = p_data->search_res.start_handle;
gl_profile_tab[PROFILE_A_APP_ID].service_end_handle = p_data->search_res.end_handle;
ESP_LOGI(GATTC_TAG, "UUID16: %x", p_data->search_res.srvc_id.uuid.uuid.uuid16);
}
break;
}
case ESP_GATTC_SEARCH_CMPL_EVT://当搜索完成时
if (p_data->search_cmpl.status != ESP_GATT_OK){
ESP_LOGE(GATTC_TAG, "search service failed, error status = %x", p_data->search_cmpl.status);
break;
}
//确定service信息的来源
if(p_data->search_cmpl.searched_service_source == ESP_GATT_SERVICE_FROM_REMOTE_DEVICE) {
ESP_LOGI(GATTC_TAG, "Get service information from remote device");
} else if (p_data->search_cmpl.searched_service_source == ESP_GATT_SERVICE_FROM_NVS_FLASH) {
ESP_LOGI(GATTC_TAG, "Get service information from flash");
} else {
ESP_LOGI(GATTC_TAG, "unknown service source");
}
ESP_LOGI(GATTC_TAG, "ESP_GATTC_SEARCH_CMPL_EVT");
if (get_server){
uint16_t count = 0;
//从cache中找类型为ESP_GATT_DB_CHARACTERISTIC的属性的个数（特征属性）
esp_gatt_status_t status = esp_ble_gattc_get_attr_count( gattc_if,
p_data->search_cmpl.conn_id,
ESP_GATT_DB_CHARACTERISTIC,
gl_profile_tab[PROFILE_A_APP_ID].service_start_handle,
gl_profile_tab[PROFILE_A_APP_ID].service_end_handle,
INVALID_HANDLE,
&count);
if (status != ESP_GATT_OK){
ESP_LOGE(GATTC_TAG, "esp_ble_gattc_get_attr_count error");
}
if (count > 0){
//给特征元素分配内存
char_elem_result = (esp_gattc_char_elem_t *)malloc(sizeof(esp_gattc_char_elem_t) * count);
if (!char_elem_result){
ESP_LOGE(GATTC_TAG, "gattc no mem");//没有足够的内存
}else{
//在cache中寻找remote_filter_char_uuid对应的特征
//由char_elem_result指向找到的特征
//count存放找到的特征个数
status = esp_ble_gattc_get_char_by_uuid( gattc_if,
p_data->search_cmpl.conn_id,
gl_profile_tab[PROFILE_A_APP_ID].service_start_handle,
gl_profile_tab[PROFILE_A_APP_ID].service_end_handle,
remote_filter_char_uuid,
char_elem_result,
&count);
if (status != ESP_GATT_OK){
ESP_LOGE(GATTC_TAG, "esp_ble_gattc_get_char_by_uuid error");
}
/* Every service have only one char in our 'ESP_GATTS_DEMO' demo, so we used first 'char_elem_result' */
if (count > 0 && (char_elem_result[0].properties & ESP_GATT_CHAR_PROP_BIT_NOTIFY)){
gl_profile_tab[PROFILE_A_APP_ID].char_handle = char_elem_result[0].char_handle;
//为service注册通知
esp_ble_gattc_register_for_notify (gattc_if, gl_profile_tab[PROFILE_A_APP_ID].remote_bda, char_elem_result[0].char_handle);
}
}
/* free char_elem_result */
free(char_elem_result);
}else{
ESP_LOGE(GATTC_TAG, "no char found");
}
}
break;
case ESP_GATTC_REG_FOR_NOTIFY_EVT: {//当一个service的通知注册完成时
ESP_LOGI(GATTC_TAG, "ESP_GATTC_REG_FOR_NOTIFY_EVT");
if (p_data->reg_for_notify.status != ESP_GATT_OK){
ESP_LOGE(GATTC_TAG, "REG FOR NOTIFY failed: error status = %d", p_data->reg_for_notify.status);
}else{
uint16_t count = 0;
uint16_t notify_en = 1;
//获取descriptor（描述符）的个数
esp_gatt_status_t ret_status = esp_ble_gattc_get_attr_count( gattc_if,
gl_profile_tab[PROFILE_A_APP_ID].conn_id,
ESP_GATT_DB_DESCRIPTOR,
gl_profile_tab[PROFILE_A_APP_ID].service_start_handle,
gl_profile_tab[PROFILE_A_APP_ID].service_end_handle,
gl_profile_tab[PROFILE_A_APP_ID].char_handle,
&count);
if (ret_status != ESP_GATT_OK){
ESP_LOGE(GATTC_TAG, "esp_ble_gattc_get_attr_count error");
}
if (count > 0){
//分配内存
descr_elem_result = malloc(sizeof(esp_gattc_descr_elem_t) * count);
if (!descr_elem_result){
ESP_LOGE(GATTC_TAG, "malloc error, gattc no mem");
}else{
//找到p_data->reg_for_notify.handle对应的描述符及其个数
ret_status = esp_ble_gattc_get_descr_by_char_handle( gattc_if,
gl_profile_tab[PROFILE_A_APP_ID].conn_id,
p_data->reg_for_notify.handle,
notify_descr_uuid,
descr_elem_result,
&count);
if (ret_status != ESP_GATT_OK){
ESP_LOGE(GATTC_TAG, "esp_ble_gattc_get_descr_by_char_handle error");
}
/* Every char has only one descriptor in our 'ESP_GATTS_DEMO' demo, so we used first 'descr_elem_result' */
if (count > 0 && descr_elem_result[0].uuid.len == ESP_UUID_LEN_16 && descr_elem_result[0].uuid.uuid.uuid16 == ESP_GATT_UUID_CHAR_CLIENT_CONFIG){
//向数组中的第一个描述符写入1
ret_status = esp_ble_gattc_write_char_descr( gattc_if,
gl_profile_tab[PROFILE_A_APP_ID].conn_id,
descr_elem_result[0].handle,
sizeof(notify_en),
(uint8_t *)¬ify_en,
ESP_GATT_WRITE_TYPE_RSP,
ESP_GATT_AUTH_REQ_NONE);
}
if (ret_status != ESP_GATT_OK){
ESP_LOGE(GATTC_TAG, "esp_ble_gattc_write_char_descr error");
}
/* free descr_elem_result */
free(descr_elem_result);
}
}
else{
ESP_LOGE(GATTC_TAG, "decsr not found");
}
}
break;
}
case ESP_GATTC_NOTIFY_EVT://当GATT通知或指示到达时
if (p_data->notify.is_notify){
ESP_LOGI(GATTC_TAG, "ESP_GATTC_NOTIFY_EVT, receive notify value:");
}else{
ESP_LOGI(GATTC_TAG, "ESP_GATTC_NOTIFY_EVT, receive indicate value:");
}
//打印通知的值
esp_log_buffer_hex(GATTC_TAG, p_data->notify.value, p_data->notify.value_len);
break;
case ESP_GATTC_WRITE_DESCR_EVT://当GATT特征描述符写入完成时
if (p_data->write.status != ESP_GATT_OK){
ESP_LOGE(GATTC_TAG, "write descr failed, error status = %x", p_data->write.status);
break;
}
ESP_LOGI(GATTC_TAG, "write descr success ");
uint8_t write_char_data[35];
for (int i = 0; i < sizeof(write_char_data); ++i)
{
write_char_data[i] = i % 256;
}
//写入特征值
esp_ble_gattc_write_char( gattc_if,
gl_profile_tab[PROFILE_A_APP_ID].conn_id,
gl_profile_tab[PROFILE_A_APP_ID].char_handle,
sizeof(write_char_data),
write_char_data,
ESP_GATT_WRITE_TYPE_RSP,
ESP_GATT_AUTH_REQ_NONE);
break;
case ESP_GATTC_SRVC_CHG_EVT: {//当service改变时
esp_bd_addr_t bda;
memcpy(bda, p_data->srvc_chg.remote_bda, sizeof(esp_bd_addr_t));
ESP_LOGI(GATTC_TAG, "ESP_GATTC_SRVC_CHG_EVT, bd_addr:");
esp_log_buffer_hex(GATTC_TAG, bda, sizeof(esp_bd_addr_t));
break;
}
case ESP_GATTC_WRITE_CHAR_EVT:
if (p_data->write.status != ESP_GATT_OK){
ESP_LOGE(GATTC_TAG, "write char failed, error status = %x", p_data->write.status);
break;
}
ESP_LOGI(GATTC_TAG, "write char success ");
break;
case ESP_GATTC_DISCONNECT_EVT://当GATT特征写入操作完成时
connect = false;
get_server = false;
ESP_LOGI(GATTC_TAG, "ESP_GATTC_DISCONNECT_EVT, reason = %d", p_data->disconnect.reason);
break;
default:
break;
}
}GAP回调函数
GAP是最基础的一个profile
作用如下：
- 启动扫描
- 对扫描到的广播包进行解析，得到广播名和广播数据
- 如果与远程设备名对上了，就建立一个直接连接
static void esp_gap_cb(esp_gap_ble_cb_event_t event, esp_ble_gap_cb_param_t *param)
{
uint8_t *adv_name = NULL;//广播名
uint8_t adv_name_len = 0;//广播名的长度
switch (event) {
case ESP_GAP_BLE_SCAN_PARAM_SET_COMPLETE_EVT: {//当扫描参数设置完成时
//the unit of the duration is second
uint32_t duration = 30;
//扫描30秒
esp_ble_gap_start_scanning(duration);
break;
}
case ESP_GAP_BLE_SCAN_START_COMPLETE_EVT://当启动扫描完成时
//scan start complete event to indicate scan start successfully or failed
if (param->scan_start_cmpl.status != ESP_BT_STATUS_SUCCESS) {
ESP_LOGE(GATTC_TAG, "scan start failed, error status = %x", param->scan_start_cmpl.status);
break;
}
ESP_LOGI(GATTC_TAG, "scan start success");
break;
case ESP_GAP_BLE_SCAN_RESULT_EVT: {//当一个扫描结果就绪时
esp_ble_gap_cb_param_t *scan_result = (esp_ble_gap_cb_param_t *)param;
switch (scan_result->scan_rst.search_evt) {
case ESP_GAP_SEARCH_INQ_RES_EVT://对等设备的查询结果
esp_log_buffer_hex(GATTC_TAG, scan_result->scan_rst.bda, 6);//打印对等设备的地址
ESP_LOGI(GATTC_TAG, "searched Adv Data Len %d, Scan Response Len %d", scan_result->scan_rst.adv_data_len, scan_result->scan_rst.scan_rsp_len);
//解析广播数据中的广播名，将其长度存入adv_name_len
adv_name = esp_ble_resolve_adv_data(scan_result->scan_rst.ble_adv,
ESP_BLE_AD_TYPE_NAME_CMPL, &adv_name_len);
ESP_LOGI(GATTC_TAG, "searched Device Name Len %d", adv_name_len);
esp_log_buffer_char(GATTC_TAG, adv_name, adv_name_len);
#if CONFIG_EXAMPLE_DUMP_ADV_DATA_AND_SCAN_RESP
if (scan_result->scan_rst.adv_data_len > 0) {
ESP_LOGI(GATTC_TAG, "adv data:");
esp_log_buffer_hex(GATTC_TAG, &scan_result->scan_rst.ble_adv[0], scan_result->scan_rst.adv_data_len);
}
if (scan_result->scan_rst.scan_rsp_len > 0) {
ESP_LOGI(GATTC_TAG, "scan resp:");
esp_log_buffer_hex(GATTC_TAG, &scan_result->scan_rst.ble_adv[scan_result->scan_rst.adv_data_len], scan_result->scan_rst.scan_rsp_len);
}
#endif
ESP_LOGI(GATTC_TAG, "\n");
//当广播扫描到的名字及其长度与远程设备名相同时
if (adv_name != NULL) {
if (strlen(remote_device_name) == adv_name_len && strncmp((char *)adv_name, remote_device_name, adv_name_len) == 0) {
ESP_LOGI(GATTC_TAG, "searched device %s\n", remote_device_name);
if (connect == false) {
connect = true;
ESP_LOGI(GATTC_TAG, "connect to the remote device.");
esp_ble_gap_stop_scanning();//停止扫描
//打开一个直接连接
esp_ble_gattc_open(gl_profile_tab[PROFILE_A_APP_ID].gattc_if, scan_result->scan_rst.bda, scan_result->scan_rst.ble_addr_type, true);
}
}
}
break;
case ESP_GAP_SEARCH_INQ_CMPL_EVT://询问完成
break;
default:
break;
}
break;
}
case ESP_GAP_BLE_SCAN_STOP_COMPLETE_EVT://停止扫描完成
if (param->scan_stop_cmpl.status != ESP_BT_STATUS_SUCCESS){
ESP_LOGE(GATTC_TAG, "scan stop failed, error status = %x", param->scan_stop_cmpl.status);
break;
}
ESP_LOGI(GATTC_TAG, "stop scan successfully");
break;
case ESP_GAP_BLE_ADV_STOP_COMPLETE_EVT://停止广播完成
if (param->adv_stop_cmpl.status != ESP_BT_STATUS_SUCCESS){
ESP_LOGE(GATTC_TAG, "adv stop failed, error status = %x", param->adv_stop_cmpl.status);
break;
}
ESP_LOGI(GATTC_TAG, "stop adv successfully");
break;
case ESP_GAP_BLE_UPDATE_CONN_PARAMS_EVT://更新连接参数完成
ESP_LOGI(GATTC_TAG, "update connection params status = %d, min_int = %d, max_int = %d,conn_int = %d,latency = %d, timeout = %d",
param->update_conn_params.status,
param->update_conn_params.min_int,
param->update_conn_params.max_int,
param->update_conn_params.conn_int,
param->update_conn_params.latency,
param->update_conn_params.timeout);
break;
default:
break;
}
}GATTC回调函数
主要作用有二：
- 如果是GATTC注册事件，则存储每个profile的GATTC的访问接口
- 调用所有或特定profile的回调处理函数
static void esp_gattc_cb(esp_gattc_cb_event_t event, esp_gatt_if_t gattc_if, esp_ble_gattc_cb_param_t *param)
{
/* If event is register event, store the gattc_if for each profile */
if (event == ESP_GATTC_REG_EVT) {
if (param->reg.status == ESP_GATT_OK) {
gl_profile_tab[param->reg.app_id].gattc_if = gattc_if;
} else {
ESP_LOGI(GATTC_TAG, "reg app failed, app_id %04x, status %d",
param->reg.app_id,
param->reg.status);
return;
}
}
/* If the gattc_if equal to profile A, call profile A cb handler,
* so here call each profile's callback */
do {
int idx;
for (idx = 0; idx < PROFILE_NUM; idx++) {
if (gattc_if == ESP_GATT_IF_NONE || /* ESP_GATT_IF_NONE, not specify a certain gatt_if, need to call every profile cb function */
gattc_if == gl_profile_tab[idx].gattc_if) {
if (gl_profile_tab[idx].gattc_cb) {
gl_profile_tab[idx].gattc_cb(event, gattc_if, param);
}
}
}
} while (0);
}主函数
void app_main(void)
{
// Initialize NVS.
esp_err_t ret = nvs_flash_init();
if (ret == ESP_ERR_NVS_NO_FREE_PAGES || ret == ESP_ERR_NVS_NEW_VERSION_FOUND) {
ESP_ERROR_CHECK(nvs_flash_erase());
ret = nvs_flash_init();
}
ESP_ERROR_CHECK( ret );
//在启动BLE之前释放掉经典蓝牙占用的存储空间
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();
ret = esp_bt_controller_init(&bt_cfg);//初始化蓝牙控制器
if (ret) {
ESP_LOGE(GATTC_TAG, "%s initialize controller failed: %s\n", __func__, esp_err_to_name(ret));
return;
}
ret = esp_bt_controller_enable(ESP_BT_MODE_BLE);//以BLE模式启动蓝牙控制器
if (ret) {
ESP_LOGE(GATTC_TAG, "%s enable controller failed: %s\n", __func__, esp_err_to_name(ret));
return;
}
ret = esp_bluedroid_init();//初始化bluedroid
if (ret) {
ESP_LOGE(GATTC_TAG, "%s init bluetooth failed: %s\n", __func__, esp_err_to_name(ret));
return;
}
ret = esp_bluedroid_enable();//启动bluedroid
if (ret) {
ESP_LOGE(GATTC_TAG, "%s enable bluetooth failed: %s\n", __func__, esp_err_to_name(ret));
return;
}
//register the callback function to the gap module
ret = esp_ble_gap_register_callback(esp_gap_cb);//注册gap回调函数
if (ret){
ESP_LOGE(GATTC_TAG, "%s gap register failed, error code = %x\n", __func__, ret);
return;
}
//register the callback function to the gattc module
ret = esp_ble_gattc_register_callback(esp_gattc_cb);//注册GATTC回调函数
if(ret){
ESP_LOGE(GATTC_TAG, "%s gattc register failed, error code = %x\n", __func__, ret);
return;
}
ret = esp_ble_gattc_app_register(PROFILE_A_APP_ID);//向GATTC模块注册应用程序回调
if (ret){
ESP_LOGE(GATTC_TAG, "%s gattc app register failed, error code = %x\n", __func__, ret);
}
esp_err_t local_mtu_ret = esp_ble_gatt_set_local_mtu(500);//设置本地MTU为500
if (local_mtu_ret){
ESP_LOGE(GATTC_TAG, "set local MTU failed, error code = %x", local_mtu_ret);
}
}