【第六课】ESP32-S3 BLE 与 WiFi 一体化通信示例

🚀 ESP32-S3 BLE 与 WiFi 一体化通信示例

本项目展示了如何使用 ESP32-S3 实现 BLE 通信接收 WiFi 配置信息，并尝试连接 WiFi，同时通过 BLE 向客户端发送心率数据和 WiFi 连接状态。

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📌 一、功能概述

• 使用 BLE 广播设备
• 提供 BLE 特性用于接收 WiFi SSID 和密码
• 自动尝试连接 WiFi，并通过 BLE 返回连接状态
• 周期性发送模拟心率数据（用于调试展示）

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⚙️ 二、核心技术与库

• BLEDevice, BLEUtils, BLEServer: ESP32 BLE API
• WiFi.h: 管理 WiFi 连接
• 使用 BLE 特性传输配置参数（如 WiFi）
• 使用 BLE notify 功能主动推送状态

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🧠 三、UUID 设置

功能描述	UUID	说明
传感器服务	180D	心率服务
心率数据特性	2A37	notify 心率
WiFi服务	180F	自定义为 WiFi 服务
WiFi配置接收特性	2A38	write，接收SSID+密码
WiFi连接状态特性	2A39	notify，返回连接结果

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🔧 四、代码结构概述

1. 初始化 BLE 服务器与服务

pServer = BLEDevice::createServer();
pService = pServer->createService(SENSOR_SERVICE_UUID);

2. 添加 BLE 特性（心率、WiFi配置、连接状态）

pHeartRateCharacteristic = pService->createCharacteristic(...);
pWiFiConfigReceiveCharacteristic = pService->createCharacteristic(...);
pWiFiConnectionStatusCharacteristic = pService->createCharacteristic(...);

3. 特性回调处理 WiFi 数据

void onWrite(BLECharacteristic *pCharacteristic) {receivedData = pCharacteristic->getValue().c_str();// 提取 SSID 和密码并连接connectToWiFi();
}

4. WiFi 连接尝试与状态反馈

WiFi.begin(wifiSSID.c_str(), wifiPassword.c_str());
if (WiFi.status() == WL_CONNECTED) {pWiFiConnectionStatusCharacteristic->setValue("连接成功");
} else {pWiFiConnectionStatusCharacteristic->setValue("连接失败");
}
pWiFiConnectionStatusCharacteristic->notify();

5. 循环中周期性发送心率数据

if (deviceConnected) {heartRate = (heartRate + 1) % 100;pHeartRateCharacteristic->setValue(...);pHeartRateCharacteristic->notify();
}

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🔍 五、BLE 客户端格式（发送 WiFi）

客户端通过如下格式写入数据至 2A38 特性：

SSID;PASSWORD

例如：

MyHomeWiFi;my_password123

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📝 六、调试输出参考

BLE广播已启动
设备已连接
接收到的数据：MyWiFi;MyPass
WiFi已连接
IP地址: 192.168.1.88

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🧩 七、应用场景

• 终端设备初始配置
• 无需物理界面完成联网
• BLE App 快速调试嵌入式设备

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📁 八、完整代码与资源

#include <BLEDevice.h>
#include <BLEUtils.h>
#include <BLEServer.h>
#include <BLE2902.h>
#include <WiFi.h>// 传感器服务UUID
#define SENSOR_SERVICE_UUID        "180D"  // 传感器服务的UUID// 心率测量特性UUID
#define HEART_RATE_CHARACTERISTIC_UUID  "2A37"  // 其他传感器特性UUID（此处可以扩展，如添加温湿度传感器等）
// #define TEMPERATURE_CHARACTERISTIC_UUID "XXXX"  
// #define HUMIDITY_CHARACTERISTIC_UUID    "YYYY"// WiFi服务UUID
#define WIFI_SERVICE_UUID           "180F"  // WiFi服务UUID，假设为此值// WiFi配置接收UUID（接收WiFi信息）
#define WIFI_CREDENTIAL_RECEIVE_UUID "2A38"  // WiFi连接状态UUID（发送WiFi连接状态）
#define WIFI_CONNECTION_STATUS_UUID "2A39"  BLECharacteristic *pHeartRateCharacteristic;
BLECharacteristic *pWiFiConfigReceiveCharacteristic;
BLECharacteristic *pWiFiConnectionStatusCharacteristic;
BLEServer *pServer;
bool deviceConnected = false;
String receivedData = "";  // 存储接收到的数据// WiFi账号和密码
String wifiSSID = "";
String wifiPassword = "";// 提前声明connectToWiFi函数
void connectToWiFi();// 设备连接/断开回调
class MyServerCallbacks : public BLEServerCallbacks {void onConnect(BLEServer* pServer) {deviceConnected = true;Serial.println("设备已连接");}void onDisconnect(BLEServer* pServer) {deviceConnected = false;Serial.println("设备已断开连接");BLEAdvertising *pAdvertising = pServer->getAdvertising();pAdvertising->start();Serial.println("BLE广播重新启动");}
};// 接收数据的特性回调
class MyCharacteristicCallbacks : public BLECharacteristicCallbacks {void onWrite(BLECharacteristic *pCharacteristic) {receivedData = pCharacteristic->getValue().c_str();Serial.print("接收到的数据：");Serial.println(receivedData);// 分离SSID和密码int separatorIndex = receivedData.indexOf(';');if (separatorIndex != -1) {wifiSSID = receivedData.substring(0, separatorIndex);wifiPassword = receivedData.substring(separatorIndex + 1);Serial.print("WiFi SSID: ");Serial.println(wifiSSID);Serial.print("WiFi Password: ");Serial.println(wifiPassword);// 尝试连接WiFiconnectToWiFi();}}
};void connectToWiFi() {Serial.println("尝试连接到WiFi...");WiFi.begin(wifiSSID.c_str(), wifiPassword.c_str());int retryCount = 0;while (WiFi.status() != WL_CONNECTED && retryCount < 20) {delay(500);Serial.print(".");retryCount++;}if (WiFi.status() == WL_CONNECTED) {Serial.println("\nWiFi已连接");Serial.print("IP地址: ");Serial.println(WiFi.localIP());// 连接成功，发送状态给APPpWiFiConnectionStatusCharacteristic->setValue("连接成功");pWiFiConnectionStatusCharacteristic->notify();} else {Serial.println("\nWiFi连接失败，请检查SSID和密码");// 连接失败，发送状态给APPpWiFiConnectionStatusCharacteristic->setValue("连接失败");pWiFiConnectionStatusCharacteristic->notify();}
}void setup() {Serial.begin(115200);BLEDevice::init("智能跑步机BLE调试");// 创建BLE服务器pServer = BLEDevice::createServer();pServer->setCallbacks(new MyServerCallbacks());// 创建传感器服务BLEService *pService = pServer->createService(SENSOR_SERVICE_UUID);// 创建心率测量特性pHeartRateCharacteristic = pService->createCharacteristic(HEART_RATE_CHARACTERISTIC_UUID,BLECharacteristic::PROPERTY_READ |BLECharacteristic::PROPERTY_NOTIFY);pHeartRateCharacteristic->setValue("HeartRate: 75 bpm");pHeartRateCharacteristic->addDescriptor(new BLE2902());// 创建WiFi配置接收特性pWiFiConfigReceiveCharacteristic = pService->createCharacteristic(WIFI_CREDENTIAL_RECEIVE_UUID,BLECharacteristic::PROPERTY_WRITE);pWiFiConfigReceiveCharacteristic->setCallbacks(new MyCharacteristicCallbacks());// 创建WiFi连接状态通知特性pWiFiConnectionStatusCharacteristic = pService->createCharacteristic(WIFI_CONNECTION_STATUS_UUID,BLECharacteristic::PROPERTY_NOTIFY);// 启动服务pService->start();// 启动广播BLEAdvertising *pAdvertising = pServer->getAdvertising();//pAdvertising->addServiceUUID(SENSOR_SERVICE_UUID);  // 只广播自定义的服务UUID——设置广播信息，确保只广播自定义的服务UUIDpAdvertising->setScanResponse(true);pAdvertising->start();Serial.println("BLE广播已启动");
}void loop() {static int heartRate = 75;if (deviceConnected) {heartRate = (heartRate + 1) % 100;String heartRateStr = "HeartRate: " + String(heartRate) + " bpm";pHeartRateCharacteristic->setValue(heartRateStr.c_str());pHeartRateCharacteristic->notify();Serial.println(heartRateStr);}delay(1000);
}

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