#include<WiFi.h>
#include "DHTesp.h"
#include <ArduinoJson.h>
#include <PubSubClient.h>
#include <WiFiClientSecure.h>
#define DHTpin 4
DHTesp dht;
//----Thông tin wifi
const char* ssid = "Wokwi-GUEST"; //Wifi connect
const char* password = ""; //Password
const char* mqtt_server = "14fb6f428b2a4658a0b471d69b25962c.s2.eu.hivemq.cloud";
const int mqtt_port = 8883;
const char* mqtt_username = "Khoanguyen"; //User
const char* mqtt_password = "dangkhoa0210"; //Password
//--------------------------------------------------
WiFiClientSecure espClient;
PubSubClient client(espClient);
unsigned long lastMsg = 0;
#define MSG_BUFFER_SIZE (50)
char msg[MSG_BUFFER_SIZE];
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(".");
}
randomSeed(micros());
Serial.println("");
Serial.println("WiFi connected");
Serial.println("IP address: ");
Serial.println(WiFi.localIP());
}
//------------Connect to MQTT Broker-----------------------------
void reconnect() {
while (!client.connected()) {
Serial.print("Attempting MQTT connection...");
String clientID = "ESPClient-";
clientID += String(random(0xffff),HEX);
if (client.connect(clientID.c_str(), mqtt_username, mqtt_password)) {
Serial.println("connected");
client.subscribe("esp32/client");
} else {
Serial.print("failed, rc=");
Serial.print(client.state());
Serial.println(" try again in 5 seconds");
delay(5000);
}
}
}
//-----Call back Method for Receiving MQTT massage---------
void callback(char* topic, byte* payload, unsigned int length) {
String incommingMessage = "";
for(int i=0; i<length;i++) incommingMessage += (char)payload[i];
Serial.println("Massage arived ["+String(topic)+"]"+incommingMessage);
}
//-----Method for Publishing MQTT Messages---------
void publishMessage(const char* topic, String payload, boolean retained){
if(client.publish(topic,payload.c_str(),true))
Serial.println("Message published ["+String(topic)+"]: "+payload);
}
void setup() {
Serial.begin(9600);
while(!Serial) delay(1);
dht.setup(DHTpin,DHTesp::DHT22);
setup_wifi();
espClient.setInsecure();
client.setServer(mqtt_server, mqtt_port);
client.setCallback(callback);
}
unsigned long timeUpdata=millis();
void loop() {
if (!client.connected()) {
reconnect();
}
client.loop();
//read DHT22
if(millis()-timeUpdata>5000){
delay(dht.getMinimumSamplingPeriod());
float h = dht.getHumidity();
float t = dht.getTemperature();
DynamicJsonDocument doc(1024);
doc["humidity"]=h;
doc["temperature"]=t;
char mqtt_message[128];
serializeJson(doc,mqtt_message);
publishMessage("esp32/dht22", mqtt_message, true);
timeUpdata=millis();
}
}
esp:0
esp:2
esp:4
esp:5
esp:12
esp:13
esp:14
esp:15
esp:16
esp:17
esp:18
esp:19
esp:21
esp:22
esp:23
esp:25
esp:26
esp:27
esp:32
esp:33
esp:34
esp:35
esp:3V3
esp:EN
esp:VP
esp:VN
esp:GND.1
esp:D2
esp:D3
esp:CMD
esp:5V
esp:GND.2
esp:TX
esp:RX
esp:GND.3
esp:D1
esp:D0
esp:CLK
dht1:VCC
dht1:SDA
dht1:NC
dht1:GND