alex9ufo 聰明人求知心切: 2025_1 Node-red & DHT22 4LED Control

2025_1 Node-red & DHT22 4LED Control

wokwi ESP32 Arduino程式

#include <WiFi.h>

#include <PubSubClient.h>

#include <DHT.h>

//Relays for switching appliances

#define Relay1            15     //D15 LED-Orangs = Water-1

#define Relay2            2     //D2   LED-Blue  = Water-2

#define Relay3            19    //D19  LED-Blue   = Motor

#define Relay4            23    //D23  LED-RED    = Fan

//Nenu For Control

int menu;

//Changs to:

#define sub1 "alex9ufo/2025/RELAY"

#define pub1 "alex9ufo/2025/DHT22"

//DHT11 for reading temperature and humidity value

#define DHTPIN            13   //D13  DHTPIN

// Uncomment whatever type you're using! 

#define DHTTYPE DHT22   // DHT 22

DHT dht(DHTPIN, DHTTYPE);

// Update these with values suitable for your network.

const char* ssid = "Wokwi-GUEST";

const char* password = "";

const char* mqtt_server = "test.mosquitto.org";  // Local IP address of Raspberry Pi

const char* username = "";

const char* pass = "";

char str_hum_data[10];

char str_temp_data[10];

WiFiClient espClient;

PubSubClient client(espClient);

unsigned long lastMsg = 0;

#define MSG_BUFFER_SIZE  (50)

char msg[MSG_BUFFER_SIZE];

int value = 0;

//===============================================

void setup_wifi() {

  delay(10);

  // We start by connecting to a WiFi network

  Serial.println();

  Serial.print("Connecting to ");

  Serial.println(ssid);

  WiFi.mode(WIFI_STA);

  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());

}

//==============================================================

void callback(char* topic, byte* payload, unsigned int length) {

  Serial.print("Message arrived [");

  Serial.print(topic);

  Serial.print("] ");

  String message="";

  for (int i = 0; i < length; i++) {

    message += (char) payload[i];  // Convert *byte to string

}

  Serial.print(message);

  if (strstr(topic, sub1))  //Button 1

{

    if (message == "1on" ) {

        digitalWrite(Relay1, HIGH);  // Turn on the LED 

}

    if (message == "1off" ) {

        digitalWrite(Relay1, LOW);  // Turn off the LED 

}

    if (message == "2on" ) {

        digitalWrite(Relay2, HIGH);  // Turn on the LED 

}

    if (message == "2off" ) {

        digitalWrite(Relay2, LOW);  // Turn off the LED 

}

    if (message == "3on" ) {

        digitalWrite(Relay3, HIGH);  // Turn on the LED 

}

    if (message == "3off" ) {

        digitalWrite(Relay3, LOW);  // Turn off the LED 

}

    if (message == "4on" ) {

        digitalWrite(Relay4, HIGH);  // Turn on the LED 

}

    if (message == "4off" ) {

        digitalWrite(Relay4, LOW);  // Turn off the LED 

}

}

  else{

    Serial.println("unsubscribed topic");

}

}

//==============================================================

void reconnect() {

  while (!client.connected()) {

    Serial.print("Attempting MQTT connection...");

    String clientId = "ESP32Client-";

    clientId += String(random(0xffff), HEX);

    // Attempt to connect

    if (client.connect(clientId.c_str(), username, pass) ) {

      Serial.println("connected");

      client.subscribe(sub1);

    } else {

      Serial.print("failed, rc=");

      Serial.print(client.state());

      Serial.println(" try again in 5 seconds");

      // Wait 5 seconds before retrying

      delay(5000);

}

}

}

//==============================================================

void setup() {

  pinMode(Relay1, OUTPUT);

  pinMode(Relay2, OUTPUT);

  pinMode(Relay3, OUTPUT);

  pinMode(Relay4, OUTPUT);

  Serial.begin(115200);

  dht.begin();

  setup_wifi();

  client.setServer(mqtt_server, 1883);

  client.setCallback(callback);

  client.subscribe(pub1);

}

//==============================================================

void loop() {

  if (!client.connected()) {

    reconnect();

}

  client.loop();

  unsigned long now = millis();

  if (now - lastMsg > 5000) {

    float hum_data = dht.readHumidity();

    Serial.println(hum_data);

    /* 4 is mininum width, 2 is precision; float value is copied onto str_sensor*/

    dtostrf(hum_data, 4, 1, str_hum_data);

    float temp_data = dht.readTemperature(); // or dht.readTemperature(true) for Fahrenheit

    dtostrf(temp_data, 4, 1, str_temp_data);

    lastMsg = now;

    Serial.println("Publish message: ");

    Serial.print("Temperature:  "); Serial.println(str_temp_data);

    //client.publish("device2/temp", str_temp_data);

    Serial.print("Humidity:  "); Serial.println(str_hum_data);

    //client.publish("device2/hum", str_hum_data);

    String pubStr ,pubStr1 ,pubStr2;

    pubStr1=String(str_temp_data);

    pubStr2=String(str_hum_data);

    pubStr=pubStr1 + "," + pubStr2;

    // Length (with one extra character for the null terminator)

    int pubStr_len = pubStr.length() + 1; 

    // Prepare the character array (the buffer) 

    char char_array[pubStr_len];

    // Copy it over 

    pubStr.toCharArray(char_array, pubStr_len);

    client.publish(pub1, char_array);

}

}

Node-Red程式

alex9ufo 聰明人求知心切