#include <WiFi.h>
#include <PubSubClient.h>
#include <DHT.h>
// WiFi
const char* ssid = "Wokwi-GUEST";
const char* password = "";
// MQTT broker
const char* mqtt_server = "broker.hivemq.com";
const int mqtt_port = 1883;
const char* mqtt_topic_temperature = "/ISTIC/TP4/INFOTRONIQUE/TEMPERATURE/";
const char* mqtt_topic_alert = "/ISTIC/TP4/INFOTRONIQUE/ALERT/";
WiFiClient espClient;
PubSubClient client(espClient);
// DHT sensor
#define DHTPIN 2
#define DHTTYPE DHT22
DHT dht(DHTPIN, DHTTYPE);
// LED pins
const int led_red = 14;
const int led_blue = 13;
void setup_wifi() {
delay(10);
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() {
while (!client.connected()) {
Serial.print("Connecting to MQTT broker...");
if (client.connect("ESP32Client")) {
Serial.println("connected");
} else {
Serial.print("failed, rc=");
Serial.print(client.state());
Serial.println(" retrying in 5 seconds");
delay(5000);
}
}
}
void read_sensor(void *pvParameters) {
(void) pvParameters;
float temperature = 0;
for (;;) {
temperature = dht.readTemperature();
Serial.print("Temperature: ");
Serial.println(temperature);
if (client.connected()) {
client.publish(mqtt_topic_temperature, String(temperature).c_str());
}
if (temperature > 25) {
digitalWrite(led_red, HIGH);
digitalWrite(led_blue, LOW);
if (client.connected()) {
client.publish(mqtt_topic_alert, "CHAUD");
}
} else if (temperature < 25) {
digitalWrite(led_red, LOW);
digitalWrite(led_blue, HIGH);
if (client.connected()) {
client.publish(mqtt_topic_alert, "FROID");
}
} else {
digitalWrite(led_red, LOW);
digitalWrite(led_blue, LOW);
}
vTaskDelay(1000 / portTICK_PERIOD_MS);
}
}
void setup() {
Serial.begin(115200);
setup_wifi();
dht.begin();
pinMode(led_red, OUTPUT);
pinMode(led_blue, OUTPUT);
client.setServer(mqtt_server, mqtt_port);
}
void loop() {
if (!client.connected()) {
reconnect();
}
client.loop();
}
void app_main() {
xTaskCreatePinnedToCore(
read_sensor, /* Function to implement the task */
"Read Sensor", /* Name of the task */
10000, /* Stack size in words */
NULL, /* Task input parameter */
1, /* Priority of the task */
NULL, /* Task handle. */
0); /* Core where the task should run */
}