/* Basic ESP8266 MQTT example This sketch demonstrates the capabilities of the pubsub library in combination with the ESP8266 board/library. It connects to an MQTT server then: - publishes "hello world" to the topic "outTopic" every two seconds - subscribes to the topic "inTopic", printing out any messages it receives. NB - it assumes the received payloads are strings not binary - If the first character of the topic "inTopic" is an 1, switch ON the ESP Led, else switch it off It will reconnect to the server if the connection is lost using a blocking reconnect function. See the 'mqtt_reconnect_nonblocking' example for how to achieve the same result without blocking the main loop. To install the ESP8266 board, (using Arduino 1.6.4+): - Add the following 3rd party board manager under "File -> Preferences -> Additional Boards Manager URLs": http://arduino.esp8266.com/stable/package_esp8266com_index.json - Open the "Tools -> Board -> Board Manager" and click install for the ESP8266" - Select your ESP8266 in "Tools -> Board" */ #include <ESP8266WiFi.h> #include <PubSubClient.h> #include <OneWire.h> #include <DallasTemperature.h> // Update these with values suitable for your network. const char* ssid = "ajfisher"; const char* password = "mrt1ckle"; const char* mqtt_server = "192.168.43.140"; const char* clientname = "ESP-01-CLIENT1234"; WiFiClient espClient; PubSubClient client(espClient); long lastMsg = 0; char msg[50]; #define WAIT_PERIOD 1000 #define ONE_WIRE_BUS 2 // DS18B20 pin OneWire oneWire(ONE_WIRE_BUS); DallasTemperature DS18B20(&oneWire); void setup() { //pinMode(BUILTIN_LED, OUTPUT); // Initialize the BUILTIN_LED pin as an output Serial.begin(115200); setup_wifi(); client.setServer(mqtt_server, 1883); // locate devices on the bus Serial.print("Locating devices..."); DS18B20.begin(); Serial.print("Found "); Serial.print(DS18B20.getDeviceCount(), DEC); Serial.println(" devices."); } void setup_wifi() { delay(10); // We start by connecting to a WiFi network 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 reconnect() { // Loop until we're reconnected while (!client.connected()) { Serial.print("Attempting MQTT connection..."); // Attempt to connect if (client.connect(clientname)) { Serial.println("connected"); // Once connected, publish an announcement... client.publish("presence", "hello from mqtt"); // ... and resubscribe //client.subscribe("tempfeed"); } else { Serial.print("failed, rc="); Serial.print(client.state()); Serial.println(" try again in 5 seconds"); // Wait 5 seconds before retrying delay(5000); } } } void loop() { if (!client.connected()) { reconnect(); } client.loop(); float temp; DS18B20.requestTemperatures(); temp = DS18B20.getTempCByIndex(0); // Serial.print("Temperature: "); // Serial.println(temp); long now = millis(); if (now - lastMsg > WAIT_PERIOD) { lastMsg = now; ((String)temp).toCharArray(msg, 50); Serial.print("Publish message: "); Serial.println(msg); client.publish("tempfeed", msg); } }