aliyun-iot-android-things-nxp: A Java repository from 223222981

aliyun-iot-androidthings-nxp

谷歌Android things物联网硬件接入阿里云IoT物联网套件云端实战

1.硬件设备

android things开发板 NXP Pico i.MX7D

NXP Pico i.MX7D 完整I/O接口文档

温湿度传感器 DHT12

DHT12支持I2C，淘宝有售

甲醛传感器 ZE08-CH2O

ZE08支持UART，淘宝有售

设备接线

2.阿里云IoT物联网套件

2.1 开通阿里云IoT物联网套件

IoT物联网套件官网地址

2.2 创建高级版产品

产品属性定义

属性名	标识符	数据类型	描述
温度	temperature	float	DHT12传感器采集
湿度	humidity	float	DHT12传感器采集
甲醛浓度	ch2o	double	ZE08传感器采集

2.3 设备端开发

a) 使用Android Studio创建Android things工程，添加网络权限

<uses-permission android:name="android.permission.INTERNET" />

b) gradle引入eclipse.paho.mqtt

implementation 'org.eclipse.paho:org.eclipse.paho.client.mqttv3:1.2.0'

c) DHT12Thermometer通过I2C读取DHT12数据

private void readDataFromI2C() {

        try {

            byte[] data = new byte[5];
            i2cDevice.readRegBuffer(0x00, data, data.length);

            // check data
            if ((data[0] + data[1] + data[2] + data[3]) % 256 != data[4]) {
                humidity = temperature = 0;
                return;
            }
            // humidity data
            humidity = Double.valueOf(String.valueOf(data[0]) + "." + String.valueOf(data[1]));
            Log.d(TAG, "humidity: " + humidity);
            // temperature data
            if (data[3] < 128) {
                temperature = Double.valueOf(String.valueOf(data[2]) + "." + String.valueOf(data[3]));
            } else {
                temperature = Double.valueOf("-" + String.valueOf(data[2]) + "." + String.valueOf(data[3] - 128));
            }

            Log.d(TAG, "temperature: " + temperature);

        } catch (IOException e) {
            Log.e(TAG, "readDataFromI2C error " + e.getMessage(), e);
        }

    }

d) Ze08CH2O通过UART获取ZE08数据

try {
    // data buffer
    byte[] buffer = new byte[9];

    while (uartDevice.read(buffer, buffer.length) > 0) {

       if (checkSum(buffer)) {
          ppbCh2o = buffer[4] * 256 + buffer[5];
          ch2o = ppbCh2o / 66.64 * 0.08;
       } else {
          ch2o = ppbCh2o = 0;
       }
       Log.d(TAG, "ch2o: " + ch2o);
     }
} catch (IOException e) {
    Log.e(TAG, "Ze08CH2O read data error " + e.getMessage(), e);
}

e) 创建阿里云IoT连接，上报数据

/*
payload格式
{
  "id": 123243,
  "params": {
    "temperature": 25.6,
    "humidity": 60.3,
    "ch2o": 0.048
  },
  "method": "thing.event.property.post"
}
*/
MqttMessage message = new MqttMessage(payload.getBytes("utf-8"));
message.setQos(1);

String pubTopic = "/sys/" + productKey + "/" + deviceName + "/thing/event/property/post";

mqttClient.publish(pubTopic, message);

223222981/aliyun-iot-android-things-nxp