前言

最近接了一个外包，发现了esp32连接小程序会有很多bug，所以接下来会慢慢更新解决方案，还是需要多接触项目才能进步呀兄弟们！

附上uuid的生成链接：

// See the following for generating UUIDs:
// https://www.uuidgenerator.net/

问题

这里借用一下，别人博客遇到的问题。

后面重新开看流程时发现使用 wx.getBLEDeviceCharacteristics的时候有出现了三个特征值，以至于报错，博主问题原链接

我们可以看到微信小程序维护的也....现在2024年了这个bug还没修好.....

链接

解决办法

问题发现

解决办法只能从esp32代码来入手，首先来看看原本的蓝牙连接代码,我们可以看到，首先在开头就写了四个uuid特征码来进行蓝牙初始化，创建、发送、接收，这就是导致问题出现的关键

#define SERVICE_UUID        "1596c77c-cf40-4137-9957-d24916f8e50b"   //你可以通过上面的网址去生成UUID
#define CHARACTERISTIC_UUID "1596c77c-cf40-4137-9957-d24916f8e50b"
#define CHARACTERISTIC_UUID_RX "1596c77c-cf40-4137-9957-d24916f8e50b"
#define CHARACTERISTIC_UUID_TX "1596c77c-cf40-4137-9957-d24916f8e50b"void setup() {chipId = String((uint32_t)ESP.getEfuseMac(), HEX);chipId.toUpperCase();
//  chipid =ESP.getEfuseMac();
//  Serial.printf("Chip id: %s\n", chipid.c_str());Serial.println("chipId:"+chipId);Serial.println();Serial.printf("Chip id: %s\n", chipId.c_str());// Create the BLE DeviceBLEDevice::init("xhn_Service");// Create the BLE ServerpServer = BLEDevice::createServer();pServer->setCallbacks(new MyServerCallbacks());//随机生成的uuid放入BLEService *pService = pServer->createService(SERVICE_UUID);// Create a BLE CharacteristicpTxCharacteristic = pService->createCharacteristic(CHARACTERISTIC_UUID_TX,  BLECharacteristic::PROPERTY_NOTIFY);pTxCharacteristic->addDescriptor(new BLE2902());BLECharacteristic * pRxCharacteristic = pService->createCharacteristic(CHARACTERISTIC_UUID_RX,                                  uuid_RX,                                                   BLECharacteristic::PROPERTY_WRITE);pRxCharacteristic->setCallbacks(new MyCallbacks());// Start the servicepService->start();// Start advertisingpServer->getAdvertising()->start();Serial.println("Waiting a client connection to notify...");
}String readString;void loop() {if (deviceConnected) {//        pTxCharacteristic->setValue(&txValue, 1);//        pTxCharacteristic->notify();//        txValue++;//    delay(10); // bluetooth stack will go into congestion, if too many packets are sent}while (Serial.available() > 0) {if (deviceConnected) {delay(3);readString += Serial.read();pTxCharacteristic->setValue(chipId.c_str());
//      pTxCharacteristic->setValue((uint32_t)ESP.getEfuseMac());pTxCharacteristic->notify();Serial.println(chipId);}}// disconnectingif (!deviceConnected && oldDeviceConnected) {delay(500); // give the bluetooth stack the chance to get things readypServer->startAdvertising(); // restart advertisingSerial.println("start advertising");oldDeviceConnected = deviceConnected;}// connectingif (deviceConnected && !oldDeviceConnected) {// do stuff here on connectingoldDeviceConnected = deviceConnected;}
}

问题解决

因为我们初始化，接收、发送时，传递的都是同一个uuid，所以导致特征码重复，而报错，所以我们就可以在初始化的时候使用一个uuid，在发送或接收使用uuid时，切换另一个，因为获取uuid的目的是为了让小程序绑定设备码，所以在初始化的时候我们就可以绑定成功，从而uuid的作用就不重要了。

这边以修改接收的uuid为例：（其实修改一行就解决问题了），或者你将发送的UUID的修改成别的uuid也可以，只要你在小程序绑定号设备号就行，因为设备号是不会改变的。

#define SERVICE_UUID        "1596c77c-cf40-4137-9957-d24916f8e50b"   //你可以通过上面的网址去生成UUID
#define CHARACTERISTIC_UUID "1596c77c-cf40-4137-9957-d24916f8e50b"
#define CHARACTERISTIC_UUID_RX "2abe697b-cad9-409b-802e-624646c3e69c"
#define CHARACTERISTIC_UUID_TX "1596c77c-cf40-4137-9957-d24916f8e50b"void setup() {chipId = String((uint32_t)ESP.getEfuseMac(), HEX);chipId.toUpperCase();
//  chipid =ESP.getEfuseMac();
//  Serial.printf("Chip id: %s\n", chipid.c_str());Serial.println("chipId:"+chipId);Serial.println();Serial.printf("Chip id: %s\n", chipId.c_str());// Create the BLE DeviceBLEDevice::init("xhn_Service");// Create the BLE ServerpServer = BLEDevice::createServer();pServer->setCallbacks(new MyServerCallbacks());//随机生成的uuid放入BLEService *pService = pServer->createService(SERVICE_UUID);// Create a BLE CharacteristicpTxCharacteristic = pService->createCharacteristic(CHARACTERISTIC_UUID_TX,  BLECharacteristic::PROPERTY_NOTIFY);pTxCharacteristic->addDescriptor(new BLE2902());BLECharacteristic * pRxCharacteristic = pService->createCharacteristic(CHARACTERISTIC_UUID_RX,                                                                                   BLECharacteristic::PROPERTY_WRITE);pRxCharacteristic->setCallbacks(new MyCallbacks());// Start the servicepService->start();// Start advertisingpServer->getAdvertising()->start();Serial.println("Waiting a client connection to notify...");
}String readString;void loop() {if (deviceConnected) {//        pTxCharacteristic->setValue(&txValue, 1);//        pTxCharacteristic->notify();//        txValue++;//    delay(10); // bluetooth stack will go into congestion, if too many packets are sent}while (Serial.available() > 0) {if (deviceConnected) {delay(3);readString += Serial.read();pTxCharacteristic->setValue(chipId.c_str());
//      pTxCharacteristic->setValue((uint32_t)ESP.getEfuseMac());pTxCharacteristic->notify();Serial.println(chipId);}}// disconnectingif (!deviceConnected && oldDeviceConnected) {delay(500); // give the bluetooth stack the chance to get things readypServer->startAdvertising(); // restart advertisingSerial.println("start advertising");oldDeviceConnected = deviceConnected;}// connectingif (deviceConnected && !oldDeviceConnected) {// do stuff here on connectingoldDeviceConnected = deviceConnected;}
}