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/*
Rui Santos
Complete project details at https://RandomNerdTutorials.com/esp8266-nodemcu-mqtt-publish-bme280-arduino/
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files.
The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.
*/
#include <Wire.h>
#include <Adafruit_Sensor.h>
#include <Adafruit_BME280.h>
#include <ESP8266WiFi.h>
#include <Ticker.h>
#include <AsyncMqttClient.h>
#define WIFI_SSID "XXXXXXXXXX"
#define WIFI_PASSWORD "XXXXXXXXXX"
// Raspberri Pi Mosquitto MQTT Broker
#define MQTT_HOST IPAddress(192, 168, XX, XX)
#define MQTT_PORT 1883
// For a cloud MQTT broker, type the domain name
//#define MQTT_HOST "example.com"
// Temperature MQTT Topics
#define MQTT_PUB_TEMP "esp/bme280/temperature"
#define MQTT_PUB_HUM "esp/bme280/humidity"
#define MQTT_PUB_PRES "esp/bme280/pressure"
// BME280 I2C
Adafruit_BME280 bme;
// Variables to hold sensor readings
float temp;
float hum;
float pres;
AsyncMqttClient mqttClient;
Ticker mqttReconnectTimer;
WiFiEventHandler wifiConnectHandler;
WiFiEventHandler wifiDisconnectHandler;
Ticker wifiReconnectTimer;
unsigned long previousMillis = 0; // Stores last time temperature was published
const long interval = 10000; // Interval at which to publish sensor readings
void connectToWifi() {
Serial.println("Connecting to Wi-Fi...");
WiFi.begin(WIFI_SSID, WIFI_PASSWORD);
}
void connectToMqtt() {
Serial.println("Connecting to MQTT...");
mqttClient.connect();
}
void onWifiConnect(const WiFiEventStationModeGotIP& event) {
Serial.println("Connected to Wi-Fi.");
connectToMqtt();
}
void onWifiDisconnect(const WiFiEventStationModeDisconnected& event) {
Serial.println("Disconnected from Wi-Fi.");
mqttReconnectTimer.detach(); // ensure we don't reconnect to MQTT while reconnecting to Wi-Fi
wifiReconnectTimer.once(2, connectToWifi);
}
void onMqttConnect(bool sessionPresent) {
Serial.println("Connected to MQTT.");
Serial.print("Session present: ");
Serial.println(sessionPresent);
}
void onMqttDisconnect(AsyncMqttClientDisconnectReason reason) {
Serial.println("Disconnected from MQTT.");
if (WiFi.isConnected()) {
mqttReconnectTimer.once(2, connectToMqtt);
}
}
/*void onMqttSubscribe(uint16_t packetId, uint8_t qos) {
Serial.println("Subscribe acknowledged.");
Serial.print(" packetId: ");
Serial.println(packetId);
Serial.print(" qos: ");
Serial.println(qos);
}
void onMqttUnsubscribe(uint16_t packetId) {
Serial.println("Unsubscribe acknowledged.");
Serial.print(" packetId: ");
Serial.println(packetId);
}*/
void onMqttPublish(uint16_t packetId) {
Serial.print("Publish acknowledged.");
Serial.print(" packetId: ");
Serial.println(packetId);
}
void setup() {
Serial.begin(115200);
Serial.println();
// Initialize BME280 sensor
if (!bme.begin(0x76)) {
Serial.println("Could not find a valid BME280 sensor, check wiring!");
while (1);
}
wifiConnectHandler = WiFi.onStationModeGotIP(onWifiConnect);
wifiDisconnectHandler = WiFi.onStationModeDisconnected(onWifiDisconnect);
mqttClient.onConnect(onMqttConnect);
mqttClient.onDisconnect(onMqttDisconnect);
//mqttClient.onSubscribe(onMqttSubscribe);
//mqttClient.onUnsubscribe(onMqttUnsubscribe);
mqttClient.onPublish(onMqttPublish);
mqttClient.setServer(MQTT_HOST, MQTT_PORT);
// If your broker requires authentication (username and password), set them below
//mqttClient.setCredentials("REPlACE_WITH_YOUR_USER", "REPLACE_WITH_YOUR_PASSWORD");
connectToWifi();
delay(2000);
// New BME280 sensor readings
//temp = bme.readTemperature();
temp = 1.8*bme.readTemperature() + 32;
hum = bme.readHumidity();
pres = bme.readPressure()/100.0F;
// Publish an MQTT message on topic esp/bme280/temperature
uint16_t packetIdPub1 = mqttClient.publish(MQTT_PUB_TEMP, 1, true, String(temp).c_str());
Serial.printf("Publishing on topic %s at QoS 1, packetId: %i ", MQTT_PUB_TEMP, packetIdPub1);
Serial.printf("Message: %.2f \n", temp);
// Publish an MQTT message on topic esp/bme280/humidity
uint16_t packetIdPub2 = mqttClient.publish(MQTT_PUB_HUM, 1, true, String(hum).c_str());
Serial.printf("Publishing on topic %s at QoS 1, packetId: %i ", MQTT_PUB_HUM, packetIdPub2);
Serial.printf("Message: %.2f \n", hum);
// Publish an MQTT message on topic esp/bme280/pressure
uint16_t packetIdPub3 = mqttClient.publish(MQTT_PUB_PRES, 1, true, String(pres).c_str());
Serial.printf("Publishing on topic %s at QoS 1, packetId: %i ", MQTT_PUB_PRES, packetIdPub3);
Serial.printf("Message: %.3f \n", pres);
Serial.println("I'm awake, but I'm going into deep sleep mode for 30 seconds");
delay(2000);
ESP.deepSleep(30e6);
}
void loop() {
}
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