ESP8266+Mixly+MIXIO+物联网小试2-DHT11温湿度

本篇主要使用esp8266将温湿度数据发送到平台MIXIO，有关更细节的Mixly和MIXIO等设置参见上篇-物联网摇杆篇。

1. MIXIO端

1.1新创建项目TempHumi

• 添加组件 TEMP 和 HUMI
  
• 组件选择仪表盘
  
• 两个组件的消息主题分别为：TEMPdata 和 HUMIdata
  
  

1.2 逻辑设置

• 逻辑编程，当接收到ESP8266发来的 TEMPdata 主题消息时向 TEMP 组件发送该消息值，该值在ESP8266 端就是DHT11的温度值。同理，再添加一个湿度消息。
  

2. Mixly端

2.1 烧录到ESP8266的代码

• 板类型选择NodeMCU 1.0 12E
• 设置esp8266连接的WiFi（非5G）
• MQTT连接设置，MIXIO用户名和密钥和项目名称
• 设置ESP8266连接到DHT11的引脚为GPIO2
• 设置变量和发送MQTT消息
• 延时3秒，官方要求发送不高于5次/500ms
  

2.2 除了在Mixly上可以编程，同样可以在Arduino IDE上烧录代码

可以将mixly上的代码复制过来，要先要安装库PubSubClient

#include <ESP8266WiFi.h>
#include <PubSubClient.h>

#include <DHT.h>

volatile double messageTEMP;
volatile int messageHUMI;
const char *mqtt_broker = "mixio.mixly.cn";
const char *mqtt_username = "bzfanfan@139.com";
const char *mqtt_password = "98834bc22885a63d5c82d6cc0c28057d";
const int mqtt_port = 1883;
String mqtt_topic = "";
String mqtt_data = "";
boolean mqtt_status = false;
String project = "TempHumi";

WiFiClient espClient;
PubSubClient client(espClient);
void callback(char *topic, byte *payload, unsigned int length) {
  String data = "";
  for (int i = 0; i < length; i++) {
    data = String(data) + String((char) payload[i]);
  }
  mqtt_topic = String(topic);
  mqtt_data = data;
  mqtt_status = true;
}

DHT dht2(2, 11);

void setup(){
  WiFi.begin("ZHIYI", "zy12345678");
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("Local IP:");
  Serial.print(WiFi.localIP());

  messageTEMP  = 0;
  messageHUMI = 0;
  client.setServer(mqtt_broker, mqtt_port);
client.setCallback(callback);
while (!client.connected()) {
  String client_id = "esp-client-";
  client_id += String(WiFi.macAddress());
  Serial.printf("The client %s connects to the public mqtt broker\n", client_id.c_str());
  if (client.connect(client_id.c_str(), mqtt_username, mqtt_password)) {
    Serial.println("Public emqx mqtt broker connected");
    client.publish(String(String(mqtt_username) +"/"+ String(project) +"/"+ String("b640a0ce465fa2a4150c36b305c1c11b")).c_str(),String(client_id).c_str());
  } else {
    Serial.print("failed with state ");
    Serial.print(client.state());
    delay(2000);
  }
}
  Serial.begin(115200);
  dht2.begin();
}

void loop(){
  client.loop();
  messageTEMP = dht2.readTemperature();
  messageHUMI = dht2.readHumidity();
  client.publish(String(String(mqtt_username) +"/"+ String(project) +"/"+ String("TEMPdata")).c_str(),String(messageTEMP).c_str());
  client.publish(String(String(mqtt_username) +"/"+ String(project) +"/"+ String("HUMIdata")).c_str(),String(messageHUMI).c_str());
  Serial.print("message:");
  Serial.print(messageTEMP);
  Serial.print("℃-messageHUMI:");
  Serial.print(messageHUMI);
  Serial.println("%");
  delay(3000);
}

3. 效果

3.1 Arduino IDE

3.2 MIXIO端

暂时没想到怎么加℃和％，如果用文本组件应该可以

预备:下篇-色盘RGB灯