Hiii everyone,
I begun since a few weeks to learn how to work with mqtt on Arduino. So i have two boards( ESP32), the first one as publisher with two sensor ( a PIR MOTION SENSOR and a fire detector). The second one with a simple lcd 1602, which works as subscriber. The first is already working perfectly so my problem now is to make the second one work as i want. In the Fact, i want to subscribe to my broker and hold the published topic, and then if the content or the value of topic give me “OK” , then a message will be written on the lcd display. Here below are the two codes for my Boards, the first for the publisher and the second one for my subscriber.
Now i just want someone to help me to get the message on the lcd when content´s topic have the value “OK”. I´ve tried this but it didn´t works.
The first One
include <Arduino.h>
#include <Adafruit_Sensor.h>
include <WiFi.h>
include <PubSubClient.h>
// wifi Daten
const char* ssid = “UPC7813368” ;
const char* password = “bu23jrYctjRr” ;
WiFiClient WifiClient ;
// MQTT Broker_Daten
const char* mqttServer = “192.168.0.220” ; // Broker-passwort
PubSubClient mqttClient( WifiClient) ;
//Topic
char FlameSate[] =“flameState”;
char Bewegung[]= “Bewegung” ;
int pirSensor= 27 ;
int ledPin = 32 ; // für meinen Bewegungsmelder
int flamePin = 34;
//Verbindung mit dem Broker herstellen
void mqttConnect()
{
Serial.print(“Verbindung zum MQTT_Server”);
Serial.print( mqttServer);
while(!mqttClient.connected())
{
Serial.print(“.”);
if (mqttClient.connect(“ES”))
{
Serial.print(“MQTT-VErbunden”);
}
else
{
Serial.print("Fehlgeschlagen ");
Serial.print(mqttClient.state());
Serial.println(“erneuter Versuch in 5 Sec”);
delay(5000);
}
}
mqttClient.subscribe(“test/esp32”);
}
void setup() {
pinMode(flamePin, INPUT); // Setze Flammensensor als Eingang
pinMode(ledPin, OUTPUT); // Setze LED als Ausgang
Serial.begin(115200);
Serial.println();
Serial.print(“Verbingsaufbaun zu”) ;
Serial.print(ssid);
WiFi.begin(ssid,password);
while(WiFi.status() != WL_CONNECTED)
{
delay(500);
Serial.print(“.”);
}
Serial.print(“”);
Serial.println(“Wifi connected”);
Serial.print(“IP Add:”);
Serial.print(WiFi.localIP());
// Verbindung mit MQTT-Server
mqttClient.setServer(mqttServer, 1883);
//mqttClient.setCallback(callback);
mqttConnect();
}
void loop() {
// Wenn der Flammensensor eine Flamme erkennt, schalte die LED ein
/* if (flameValue > 100) { // Der Schwellenwert von 100 muss möglicherweise angepasst werden
digitalWrite(ledPin, HIGH); // Schalte LED ein
} else {
digitalWrite(ledPin, LOW); // Schalte LED aus
} */
if(!mqttClient.connected())
{
mqttConnect();
}
mqttClient.loop();
int flameValue = analogRead(flamePin); // Lese analoge Spannung vom Flammensensor
if(flameValue > 100)
{
Serial.print(“Achtung Fire, Feuerwehr Anrufen !!!”);
mqttClient.publish(FlameSate, “OK”);
}
else
{
Serial.print(“Sicher, Kein Feuer !”);
mqttClient.publish(FlameSate, “Nein”);
}
int pirSensorValue = digitalRead(pirSensor);
if(pirSensorValue== HIGH)
{
digitalWrite(ledPin, HIGH) ;
Serial.print(“Bewegung erkannt”);
mqttClient.publish(Bewegung, “OK”);
delay(1000) ;
}
else
{
digitalWrite(ledPin, LOW);
Serial.print(“Keine Bewegung”);
mqttClient.publish(Bewegung, “Nein”);
delay(1000) ;
}
delay(200);
}
The Second One where help is needed
#include <Arduino.h>
#include <LiquidCrystal.h>
#include <Adafruit_Sensor.h>
#include <Wifi.h>
include <PubSubClient.h>
// Lcd initialisierung
LiquidCrystal lcd(22,21,5,18,23,19);
// Encoder
int Clk= 33;
int Data= 25;
int SwBut = 25;
int menu =1 ;
static int LastState ;
// wifi Daten
const char* ssid = “UPC7813368” ;
const char* password = “bu23jrYctjRr” ;
WiFiClient WifiClient ;
// MQTT Broker_Daten
const char* mqttServer = “192.168.0.220” ;
PubSubClient mqttClient( WifiClient) ;
// Topic für mqtt
//Topic
char FlameSate[] =“flameState”;
char Bewegung[]= “Bewegung” ;
byte* payload;
//Verbindung mit dem Broker herstellen
void mqttConnect()
{
Serial.print(“Verbindung zum MQTT_Server”);
Serial.print( mqttServer);
while(!mqttClient.connected())
{
Serial.print(“.”);
if (mqttClient.connect(“ES”))
{
Serial.print(“MQTT-VErbunden”);
}
else
{
Serial.print(“Fehlgeschlagen, rc=”);
Serial.print(mqttClient.state());
Serial.println(“erneuter Versuch in 5 Sec”);
delay(5000);
}
}
mqttClient.subscribe(“test/esp32”);
}
//Callback Nachrichten-Empfang (Subscribe)
void callback( char* topic, byte* message, unsigned int length)
{
Serial.print("topic: ") ;
Serial.print(topic) ;
String str ;
for (int i =0 ; i< length ; i++)
{
str += (char)message[i];
}
Serial.print( "Nachrichtenempfang für topic: ");
Serial.print(topic);
Serial.print(“Nachricht :”);
Serial.println(str);
}
/void callback(char topic, byte* payload, unsigned int length) {
Serial.print("Message arrived on topic: ");
Serial.println(topic);
Serial.print("Payload: ");
for (int i = 0; i < length; i++) {
Serial.print((char)payload[i]);
}
Serial.println();
if (strcmp(topic, FlameSate) == 0) {
if (strcmp((char*)payload, “OK”) == 0) {
lcd.clear();
lcd.setCursor(0, 0);
lcd.println(“OK Feuer”);
lcd.display();
}
} else if (strcmp(topic, Bewegung) == 0) {
if (strcmp((char*)payload, “OK”) == 0) {
lcd.clear();
lcd.setCursor(0, 0);
lcd.println(“OK Bewegung”);
lcd.display();
}
}
}
*/
void setup()
{
lcd.begin(16, 2);
// Wifi Verbindung
Serial.begin(115200);
Serial.println();
Serial.print(“Verbingsaufbaun zu”) ;
Serial.print(ssid);
WiFi.begin(ssid,password);
while(WiFi.status() != WL_CONNECTED)
{
delay(500);
Serial.print(“.”);
}
Serial.print(“”);
Serial.println(“Wifi connected”);
Serial.print(“IP Add:”);
Serial.print(WiFi.localIP());
// Verbindung mit MQTT-Server
mqttClient.setServer(mqttServer, 1883);
mqttClient.setCallback(callback);
mqttConnect();
}
void loop()
{
if (!mqttClient.connected()) {
mqttConnect();
}
// mqttClient.subscribe(Bewegung) ;
// mqttClient.subscribe(FlameSate) ;
lcd.display();
mqttClient.loop();
}
Sorry but some Part of the Code are actually written in german, so i hope you can help me to better understand how to works with mqtt. Thanks