安裝ArduinoIDE 與註冊Server帳號
Arduino IDE https://www.arduino.cc/en/Main/Software
免費註冊Server帳號 https://www.adafruit.com/
NodeMCU的範例程式如下，用Arduino IDE去編譯，程式有幾各地方要去修改。
1.WLAN_SSID 請輸入你的wifi SSID
2.WLAN_PASS 請輸入你的wifi 密碼
3.AIO_USERNAME 請輸入註冊Server的帳號 https://www.adafruit.com/
4.AIO_KEY 請先登入 https://io.adafruit.com ，點選View AIO Key，複製Active Key，如下圖示。
程式內容就請大家自行研究了，不另外說明了。
關於MQTT協定，可以參考以下路徑的文章。
在編譯程式之前，請先在Arduino IDE自行匯入以下的程式庫(草稿碼->匯入程式庫->管理程式庫)，這樣編譯才不會出現錯誤。
1.Adafruit_ESP8266
2.Adafruit_MQTT_Library
3.DHT_sensor_library
/****************************************************/ #include "ESP8266WiFi.h" #include "Adafruit_MQTT.h" #include "Adafruit_MQTT_Client.h" #include "DHT.h" /************************* LED *********************************************/ #define G_LED 2 #define B_LED 0 #define R_LED 4 /*********************** DHT11 **********************************************/ #define DHTPIN 5 // what digital pin we're connected to #define DHTTYPE DHT11 // DHT 11 DHT dht(DHTPIN, DHTTYPE); /************************* WiFi Access Point *********************************/ #define WLAN_SSID "...your SSID..." #define WLAN_PASS "..your password..." /************************* Adafruit.io Setup *********************************/ #define AIO_SERVER "io.adafruit.com" #define AIO_SERVERPORT 1883 // use 1883 for SSL #define AIO_USERNAME "...your AIO username (see https://accounts.adafruit.com)..." #define AIO_KEY "...your AIO key..." /************ Global State (you don't need to change this!) ******************/ // Create an ESP8266 WiFiClient class to connect to the MQTT server. WiFiClient client; // or... use WiFiFlientSecure for SSL //WiFiClientSecure client; // Setup the MQTT client class by passing in the WiFi client and MQTT server and login details. Adafruit_MQTT_Client mqtt(&client, AIO_SERVER, AIO_SERVERPORT, AIO_USERNAME, AIO_KEY); /****************************** Feeds ***************************************/ // Setup a feed called 'photocell' for publishing. // Notice MQTT paths for AIO follow the form: /feeds/ Adafruit_MQTT_Publish Humidity = Adafruit_MQTT_Publish(&mqtt, AIO_USERNAME "/feeds/Humidity"); Adafruit_MQTT_Publish Temperature = Adafruit_MQTT_Publish(&mqtt, AIO_USERNAME "/feeds/Temperature"); // Setup a feed called 'onoff' for subscribing to changes. Adafruit_MQTT_Subscribe onoffbutton = Adafruit_MQTT_Subscribe(&mqtt, AIO_USERNAME "/feeds/onoff"); /*************************** Sketch Code ************************************/ // Bug workaround for Arduino 1.6.6, it seems to need a function declaration // for some reason (only affects ESP8266, likely an arduino-builder bug). void MQTT_connect(); void setup() { pinMode(G_LED, OUTPUT); pinMode(B_LED, OUTPUT); pinMode(R_LED, OUTPUT); digitalWrite(G_LED, LOW); digitalWrite(B_LED, LOW); digitalWrite(R_LED, LOW); Serial.begin(115200); dht.begin(); delay(10); Serial.println(F("Adafruit MQTT demo")); // Connect to WiFi access point. Serial.println(); Serial.println(); Serial.print("Connecting to "); Serial.println(WLAN_SSID); WiFi.begin(WLAN_SSID, WLAN_PASS); while (WiFi.status() != WL_CONNECTED) { delay(500); Serial.print("."); } Serial.println(); Serial.println("WiFi connected"); Serial.println("IP address: "); Serial.println(WiFi.localIP()); // Setup MQTT subscription for onoff feed. mqtt.subscribe(&onoffbutton); digitalWrite(G_LED, HIGH); digitalWrite(B_LED, HIGH); digitalWrite(R_LED, HIGH); } //uint32_t x=0; //uint32_t y=0; void loop() { // Ensure the connection to the MQTT server is alive (this will make the first // connection and automatically reconnect when disconnected). See the MQTT_connect // function definition further below. MQTT_connect(); // this is our 'wait for incoming subscription packets' busy subloop // try to spend your time here Adafruit_MQTT_Subscribe *subscription; while ((subscription = mqtt.readSubscription(5000))) { if (subscription == &onoffbutton) { Serial.print(F("Got: ")); Serial.println((char *)onoffbutton.lastread); if( *onoffbutton.lastread == '1') { digitalWrite(G_LED, LOW); } else if( *onoffbutton.lastread == '2') { digitalWrite(B_LED, LOW); } else if( *onoffbutton.lastread == '3') { digitalWrite(R_LED, LOW); } else if( *onoffbutton.lastread == '0') { digitalWrite(G_LED, HIGH); digitalWrite(B_LED, HIGH); digitalWrite(R_LED, HIGH); } } } // Now we can publish stuff! float h = dht.readHumidity(); Serial.print(F("\nHumidity : ")); Serial.print(h); Serial.print("%"); if (! Humidity.publish(h)) { Serial.println(F("\nSending Humidty is Failed")); } else { Serial.println(F("\nSending Humidty is OK!")); } // float t = dht.readTemperature(); float hic = dht.computeHeatIndex(t, h, false); Serial.print(F("\nTemperature : ")); Serial.print(hic); Serial.print("*C"); if (! Temperature.publish(hic)) { Serial.println(F("\nSending Temperature is Failed")); } else { Serial.println(F("\nSending Temperature is OK!")); } // ping the server to keep the mqtt connection alive // NOT required if you are publishing once every KEEPALIVE seconds /* if(! mqtt.ping()) { mqtt.disconnect(); } */ } // Function to connect and reconnect as necessary to the MQTT server. // Should be called in the loop function and it will take care if connecting. void MQTT_connect() { int8_t ret; // Stop if already connected. if (mqtt.connected()) { return; } Serial.print("Connecting to MQTT... "); uint8_t retries = 3; while ((ret = mqtt.connect()) != 0) { // connect will return 0 for connected Serial.println(mqtt.connectErrorString(ret)); Serial.println("Retrying MQTT connection in 5 seconds..."); mqtt.disconnect(); delay(5000); // wait 5 seconds retries--; if (retries == 0) { // basically die and wait for WDT to reset me while (1); } } Serial.println("MQTT Connected!"); }
