#include <WiFi.h>
#include <PubSubClient.h>
#include <ESP32Servo.h>
Servo myservo; // Servo object
const char* ssid = "Wokwi-GUEST";
const char* password = "";
const char* mqtt_server = "test.mosquitto.org"; // MQTT broker
WiFiClient espClient;
PubSubClient client(espClient);
long lastMsg = 0;
char msg[50];
int value = 0;
const int ledPin = 4; // Define LED pin
void setup() {
Serial.begin(115200);
myservo.attach(17); // Attach servo to GPIO 5
pinMode(ledPin, OUTPUT); // Set LED pin as output
digitalWrite(ledPin, LOW); // Initialize LED to OFF
setup_wifi();
client.setServer(mqtt_server, 1883);
client.setCallback(callback);
}
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 callback(char* topic, byte* payload, unsigned int length) {
String message;
Serial.print("Message arrived [");
Serial.print(topic);
Serial.print("] ");
for (int i = 0; i < length; i++) {
message += ((char)payload[i]);
}
Serial.println(message);
if (String(topic) == "/ThinkIOT/Servo-nodered") { // Corrected comparison
int status = message.toInt();
int pos = map(status, 1, 100, 0, 180);
Serial.println(pos);
digitalWrite(ledPin, HIGH); // Turn ON LED while servo is operating
myservo.write(pos);
delay(15);
digitalWrite(ledPin, LOW); // Turn OFF LED after servo move
}
}
void reconnect() {
while (!client.connected()) {
Serial.print("Attempting MQTT connection...");
if (client.connect("ESPClient")) {
Serial.println("connected");
client.subscribe("/ThinkIOT/Servo-nodered");
} else {
Serial.print("failed, rc=");
Serial.print(client.state());
Serial.println(" try again in 5 seconds");
delay(5000);
}
}
}
void loop() {
if (!client.connected()) {
reconnect();
}
client.loop();
delay(100);
}