接[上一篇部落格](https://www.cnblogs.com/ZhengBlogs/p/esp8266_1.html)，這次還是關於 **esp8266** --> **物聯網** # 一、雲端資料監控：DHT11 + NodeMcu +Dweet.io 1. 接上一篇部落格的接線及相關配置不變( DHT11 + NodeMcu ) 2. 配置 [Dweet.io](http://dweet.io/) > Dweet.io 是一個可以通過非常簡易的方式為物聯網裝置提供通訊服務（包括報警等）的雲端平臺。它不需要任何的設定或註冊步驟，只要終端裝置連線上網際網路，即可直接釋出或訂閱資料。 > 通過 Dweet.io 提供的雲端服務，可以很方便的將感測器資料釋出到線上平臺並實時地進行遠端監控。 - Dweeting(傳送資料到雲端) - 呼叫URL: `https://dweet.io/dweet/for/my-thing-name?hello=world&foo=bar` - Get Dweeting - 獲取最新發布的 dweet : `https://dweet.io/get/latest/dweet/for/my-thing-name` - 獲取某個名字下所有的 dweets : `https://dweet.io/get/dweets/for/my-thing-name` ``` $ http -b "https://dweet.io/get/dweets/for/rollingstarky" { "by": "getting", "the": "dweets", "this": "succeeded", "with": [ { "content": { "foo": "bar", "hello": "world" }, "created": "2020-09-25T16:30:34.524Z", "thing": "rollingstarky" }, { "content": { "foo": "bar", "hello": "world" }, "created": "2020-09-25T16:10:46.694Z", "thing": "rollingstarky" } ] } ``` 3. 專案程式碼 把上篇部落格的資料傳送到 Dweet.io 雲端平臺 ``` #include #include "DHT.h" // WiFi parameters const char* ssid = "wifi-name"; const char* password = "wifi-password"; #define DHTPIN 5 #define DHTTYPE DHT11 // Initialize DHT sensor DHT dht(DHTPIN, DHTTYPE, 15); const char* host = "dweet.io"; void setup() { Serial.begin(115200); delay(10); dht.begin(); // Connecting to a WiFi network Serial.println(); Serial.println(); Serial.print("Connecting to "); Serial.println(ssid); WiFi.begin(ssid, password); while (WiFi.status() != WL_CONNECTED) { delay(500); Serial.print("."); } Serial.println(""); Serial.println("WiFi connected"); Serial.println("IP address: "); Serial.println(WiFi.localIP()); } void loop() { Serial.print("Connecting to "); Serial.println(host); // Use WiFiClient class to create TCP connections WiFiClient client; const int httpPort = 80; if (!client.connect(host, httpPort)) { Serial.println("connection failed"); return; } // Reading temperature and humidity float h = dht.readHumidity(); float t = dht.readTemperature(); while (isnan(h) || isnan(t)) { Serial.println("Failed to read from DHT sensor!"); delay(2000); // Get the measurements once more h = dht.readHumidity(); t = dht.readTemperature(); } Serial.println(); Serial.println("The temperature and humidity are:"); Serial.println(t); Serial.println(h); // Send the request to the server client.print(String("GET /dweet/for/rollingstarkyesp8266?temperature=") + String(t) + "&humidity=" + String(h) + " HTTP/1.1\r\n" + "Host: " + host + "\r\n" + "Connection: close\r\n\r\n"); unsigned long timeout = millis(); while (client.available() == 0) { if (millis() - timeout > 5000) { Serial.println(">>> Client Timeout !"); client.stop(); return; } } // Read all the lines of the reply from server and print them to Serial while(client.available()){ String line = client.readStringUntil('\r'); Serial.print(line); } Serial.println(); Serial.println("closing connection"); Serial.println(); // Repeat every 10 seconds delay(10000); } ``` - 訪問最新更新的資料：`https://dweet.io/get/latest/dweet/for/rollingstarkyesp8266` > {"this":"succeeded","by":"getting","the":"dweets","with":[{"thing":"rollingstarkyesp8266","created":"2020-09-25T09:27:22.823Z","content":{"temperature":28,"humidity":61}}]} - 訪問全部資料：`https://dweet.io/get/dweets/for/rollingstarkyesp8266` > {"this":"succeeded","by":"getting","the":"dweets","with":[{"thing":"rollingstarkyesp8266","created":"2020-09-25T09:17:04.292Z","content":{"temperature":27.9,"humidity":58}},{"thing":"rollingstarkyesp8266","created":"2020-09-25T09:15:08.961Z","content":{"temperature":27.9,"humidity":59}},{"thing":"rollingstarkyesp8266","created":"2020-09-25T09:13:16.383Z","content":{"temperature":27.9,"humidity":58}},{"thing":"rollingstarkyesp8266","created":"2020-09-25T09:11:30.363Z","content":{"temperature":27.9,"humidity":57}},{"thing":"rollingstarkyesp8266","created":"2020-09-25T09:09:43.309Z","content":{"temperature":27.9,"humidity":57}}]} - 訪問視覺化圖表：`http://dweet.io/follow/rollingstarkyesp8266` - 這裡有點見鬼，出不來，單資料應該是都到雲端了，可以查到 Json 資料（假裝有圖有真相）  4. 連結 freeboard 平臺（儀表盤） - 註冊 - 懂點英語，稍微摸索一下  #二、遠端控制物聯網裝置：NodeMcu + PubSubClient + aREST 1.準備工具 - aREST 庫 > aREST 框架可以為一些常見的嵌入式開發板提供 RESTful 介面，支援通過串列埠、Wi-Fi、乙太網、藍芽等硬體傳送命令至開發板，激發特定的操作，並將資料以 JSON 的格式返回給控制端使用者 - PubSubClient 庫 2. 原始碼 ``` // Import required libraries #include #include #include // Clients WiFiClient espClient; PubSubClient client(espClient); // Create aREST instance aREST rest = aREST(client); // Unique ID to identify the device for cloud.arest.io char* device_id = "wuwu380"; // WiFi parameters const char* ssid = "wifi-name"; const char* password = "wifi-password"; // Callback functions void callback(char* topic, byte* payload, unsigned int length); void setup(void) { // Start Serial Serial.begin(115200); // Set callback client.setCallback(callback); // Give name and ID to device rest.set_id(device_id); rest.set_name("devices_control"); // Connect to WiFi WiFi.begin(ssid, password); while (WiFi.status() != WL_CONNECTED) { delay(500); Serial.print("."); } Serial.println(""); Serial.println("WiFi connected"); // Set output topic char* out_topic = rest.get_topic(); } void loop() { // Connect to the cloud rest.handle(client); } // Handles message arrived on subscribed topic(s) void callback(char* topic, byte* payload, unsigned int length) { rest.handle_callback(client, topic, payload, length); } ``` 3. 執行結果 > $ http -b https://cloud.arest.io/wuwu380/name > { > "connected": true, > "hardware": "esp8266", > "id": "wuwu380", > "name": "devices_control", > "variables": {} > } > $ http -b https://cloud.arest.io/wuwu380/mode/5/o > { > "connected": true, > "hardware": "esp8266", > "id": "wuwu380", > "message": "Pin D5 set to output", > "name": "devices_control" > } > $ http -b https://cloud.arest.io/wuwu380/digital/5/1 > { > "connected": true, > "hardware": "esp8266", > "id": "wuwu380", > "message": "Pin D5 set to 1", > "name": "devices_control" > } #三、 esp8266 連線 OLED 屏，製作天氣時鐘 我一開始就想做這個了，一開始當成終極目標，現在看看，九折水瓶 :) 1. 必要元件 - U8G2 螢幕驅動庫 - 可以去 Ardunio 下載，也可以把 [U8g2.rar](https://wwa.lanzous.com/iYHA3gxaigd) 解壓到 **libraries** 資料夾 2. 接線 | OLED | NodeMcu | | : - : | : - : | | GND | GND | | VCC | 3V3/5V | | SCL | D1 | | SDA | D2 | 3. 載入程式 **檔案** - **示例** - **U8G2** - **full_buffer** - 任意開啟一個，去除下行程式碼的註釋 `U8G2_SSD1306_128X64_NONAME_F_SW_I2C u8g2(U8G2_R0, /* clock=*/ SCL, /* data=*/ SDA, /* reset=*/ U8X8_PIN_NONE); // All Boards without Reset of the Display` 寫入程式  一切的學習，都是從 hello world 開始