可以接收蓝牙设备的数据，但写入得不到对应的反馈数据 相关代码片段如下（字节数不超过20，也有延时处理）

MG4J2CH/A 苹果6  8.3     微信版本6.7.4

华为畅享8        安卓8.0.0  微信版本7.0.13

 //取蓝牙服务特征值
  getBLEDeviceCharacteristics(deviceId, serviceId) {
      wx.getBLEDeviceCharacteristics({
          deviceId,
          serviceId,
          success: (res) => {
              console.log("getBLEDeviceCharacteristics");
              console.log(res);
              for (let i = 0; i < res.characteristics.length; i++) {
                  let item = res.characteristics[i]
                  console.log(item);
                  if (item.properties.notify || item.properties.indicate) {
                      wx.notifyBLECharacteristicValueChange({
                          deviceId,
                          serviceId,
                          characteristicId: item.uuid,
                          state: true,
                          success: function (res) {
                              console.log("notifyBLECharacteristicValueChange");
                              console.log(res);
                          }
                      });
                  }
                  if (item.properties.write) {

                      let uuid = item.uuid;
                      if(arr_info[serviceId])
                      {
                          arr_info[serviceId].push(uuid);
                      }else{
                          arr_info[serviceId] = [uuid];
                      }

                      this.writeBLECharacteristicValue(deviceId, serviceId, uuid);
                  }
              }
          },
          fail(res) {
              console.error('getBLEDeviceCharacteristics', res)
          }
      })
    // 操作之前先监听，保证第一时间获取数据
  wx.onBLECharacteristicValueChange((characteristic) => {
      console.log("onBLECharacteristicValueChange");
      console.log(characteristic);
      let value = new Uint8Array(characteristic.value);
      getUint8Value(characteristic.value, function (res) {
          console.log(res);
      });
  })
  },
    
    //写入一个特征值 预期在onBLECharacteristicValueChange拿到蓝牙设备传输过来的反馈数据
    writeBLECharacteristicValue(deviceId, serviceId, characteristicId) {
    let buffer = new ArrayBuffer(6);
    let dataView = new DataView(buffer);
    //判断是否开启鉴权的命令  
    dataView.setUint8(0, 0xa5); //头部
    dataView.setUint8(1, 0x01); //
    dataView.setUint8(2, 0x04); //命令字
    dataView.setUint8(4, 0x00); //流水号
    dataView.setUint8(3, 0x23); 
    dataView.setUint8(5, 0x57); //校验
    setTimeout(()=>{
        console.log(arr_info); //{"serviceId1": [uuid1, uuid2], "serviceId2": [uuid1, uuid2] }
        console.log(Object.keys(arr_info));
        let keys = Object.keys(arr_info);
        wx.writeBLECharacteristicValue({
            deviceId: deviceId,
            serviceId: keys[1], //serviceId,
            characteristicId:   arr_info[keys[1]][0],//characteristicId,
            value: buffer,
            success(res){
                console.log('writeBLECharacteristicValue success', res)
            },
            fail(err){
                console.log('writeBLECharacteristicValue fail', err)
            }
        })
    }, 5000);

你好，麻烦具体描述问题流程，提供出现问题的具体机型、微信版本号、系统版本号，以及能复现问题的代码片段https://developers.weixin.qq.com/miniprogram/dev/devtools/minicode.html