esp32蓝牙发送数据，读取发

您好！您的问题是关于ESP32蓝牙发送和读取数据的。下面是简要的回答：

要在ESP32上使用蓝牙通信，您需要使用ESP-IDF中的蓝牙库。以下是一个简单的代码示例，演示如何在ESP32上使用蓝牙发送和接收数据：

#include "esp_bt.h"
#include "esp_bt_main.h"
#include "esp_gap_ble_api.h"

#define GATTS_TAG "GATTS_DEMO"

#define PROFILE_NUM 1
#define PROFILE_A_APP_ID 0
#define ESP_APP_ID 0x55
#define SAMPLE_DEVICE_NAME "ESP_GATTS_DEMO"

static uint8_t adv_config_done = 0;

static esp_ble_adv_params_t adv_params = {
    .adv_int_min        = 0x20,
    .adv_int_max        = 0x40,
    .adv_type           = ADV_TYPE_NONCONN_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 = {
    .set_scan_rsp        = false,
    .include_name        = true,
    .include_txpower     = true,
    .min_interval        = 0,
    .max_interval        = 0,
    .appearance          = 0,
    .manufacturer_len    = 0,
    .p_manufacturer_data = NULL,
    .service_data_len    = 0,
    .p_service_data      = NULL,
    .service_uuid_len    = 0,
    .p_service_uuid      = NULL,
    .flag                = (ESP_BLE_ADV_FLAG_GEN_DISC | ESP_BLE_ADV_FLAG_BREDR_NOT_SPT),
};

static esp_ble_gatts_cb_t gatts_cb;

static void gap_event_handler(esp_gap_ble_cb_event_t event, esp_ble_gap_cb_param_t *param)
{
    switch (event) {
        case ESP_GAP_BLE_ADV_DATA_SET_COMPLETE_EVT:
            adv_config_done &= (~ADV_CONFIG_FLAG);
            if (adv_config_done == 0) {
                esp_ble_gap_start_advertising(&adv_params);
            }
            break;
        case ESP_GAP_BLE_ADV_START_COMPLETE_EVT:
            if (param->adv_start_cmpl.status != ESP_BT_STATUS_SUCCESS) {
                ESP_LOGE(GATTS_TAG, "Advertising start failed\n");
            }
            break;
        case ESP_GAP_BLE_ADV_STOP_COMPLETE_EVT:
            if (param->adv_stop_cmpl.status != ESP_BT_STATUS_SUCCESS) {
                ESP_LOGE(GATTS_TAG, "Advertising stop failed\n");
            } else {
                ESP_LOGI(GATTS_TAG, "Stop adv successfully\n");
            }
            break;
        case ESP_GAP_BLE_UPDATE_CONN_PARAMS_EVT:
            ESP_LOGI(GATTS_TAG, "Update connetion params status = %d\n", param->update_conn_params.status);
            break;
        default:
            break;
    }
}

static void gatts_event_handler(esp_gatts_cb_event_t event, esp_gatt_if_t gatts_if, esp_ble_gatts_cb_param_t *param)
{
    switch (event) {
        case ESP_GATTS_REG_EVT:
            esp_err_t set_dev_name_ret = esp_ble_gap_set_device_name(SAMPLE_DEVICE_NAME);
            if (set_dev_name_ret) {
                ESP_LOGE(GATTS_TAG, "set device name failed, error code = %x", set_dev_name_ret);
            }

            esp_err_t create_adv_config_ret = esp_ble_gap_config_adv_data(&adv_data);
            if (create_adv_config_ret) {
                ESP_LOGE(GATTS_TAG, "config adv data failed, error code = %x", create_adv_config_ret);
            }
            adv_config_done |= ADV_CONFIG_FLAG;

            esp_err_t start_adv_ret = esp_ble_gap_start_advertising(&adv_params);
            if (start_adv_ret) {
                ESP_LOGE(GATTS_TAG, "start adv failed, error code = %x", start_adv_ret);
            }
            break;
        case ESP_GATTS_CONNECT_EVT:
            ESP_LOGI(GATTS_TAG, "ESP_GATTS_CONNECT_EVT");
            break;
        case ESP_GATTS_DISCONNECT_EVT:
            ESP_LOGI(GATTS_TAG, "ESP_GATTS_DISCONNECT_EVT");
            break;
        case ESP_GATTS_READ_EVT:
            ESP_LOGI(GATTS_TAG, "ESP_GATTS_READ_EVT");
            break;
        case ESP_GATTS_WRITE_EVT:
            ESP_LOGI(GATTS_TAG, "ESP_GATTS_WRITE_EVT");
            esp_gatt_status_t status = ESP_GATT_OK;
            esp_gatt_rsp_t rsp = {0};
            rsp.attr_value.handle = param->write.handle;
            rsp.attr_value.len = param->write.len;
            rsp.attr_value.auth_req = ESP_GATT_AUTH_REQ_NONE;
            memcpy(rsp.attr_value.value, param->write.value, param->write.len);
            esp_ble_gatts_send_response(gatts_if, param->write.conn_id, param->write.trans_id, status, &rsp);
            break;
        default:
            break;
    }
}

void app_main()
{
    esp_err_t ret;

    esp_bt_controller_config_t bt_cfg = BT_CONTROLLER_INIT_CONFIG_DEFAULT();
    ret = esp_bt_controller_init(&bt_cfg);
    if (ret) {
        ESP_LOGE(GATTS_TAG, "%s initialize controller failed: %s\n", __func__, esp_err_to_name(ret));
        return;
    }

    ret = esp_bt_controller_enable(ESP_BT_MODE_BTDM);
    if (ret) {
        ESP_LOGE(GATTS_TAG, "%s enable controller failed: %s\n", __func__, esp_err_to_name(ret));
        return;
    }

    ret = esp_bluedroid_init();
    if (ret) {
        ESP_LOGE(GATTS_TAG, "%s init bluetooth failed: %s\n", __func__, esp_err_to_name(ret));
        return;
    }

    ret = esp_bluedroid_enable();
    if (ret) {
        ESP_LOGE(GATTS_TAG, "%s enable bluetooth failed: %s\n", __func__, esp_err_to_name(ret));
        return;
    }

    esp_ble_gatts_register_callback(gatts_event_handler);
    esp_ble_gap_register_callback(gap_event_handler);
    esp_ble_gatts_app_register(PROFILE_A_APP_ID);
}

在这个示例中，我们注册了一个`gatts_event_handler()`，它会处理所有GATT服务器事件。在这个函数中，我们检测到`ESP_GATTS_WRITE_EVT`事件，它发生在远程GATT客户端写入数据时。我们在这里处理接收到的数据，并将其发送回客户端。

要发送数据，您可以使用`esp_ble_gatts_send_indicate()`函数。以下是一个简单的示例，演示如何在ESP32上发送数据：

esp_gatt_status_t status = ESP_GATT_OK;
esp_ble_gatts_send_indicate(gatts_if, conn_id, attr_handle, data_len, data, false);

在这个示例中，我们使用`esp_ble_gatts_send_indicate()`函数发送数据。该函数需要以下参数：

- `gatts_if`：GATT服务器接口
- `conn_id`：连接标识符
- `attr_handle`：属性句柄
- `data_len`：要发送的数据长度
- `data`：要发送的数据
- `need_confirm`：是否需要确认

希望这些代码对您有所帮助！