Project MQTT LED dan Relay
Project MQTT LED dan Relay
Project ini untuk on/off output seperti LED, Pompa Air, dll dari jarak jauh dengan komunikasi MQTT (lebih realtime dan cepat).
Dalam MQTT, kita akan mengenal istilah:
publish, yaitu mengirimkan data (ESP --> Cloud, Cloud --> ESP)
subscribe, yaitu menerima data yang dipublish (ESP --> Cloud, Cloud --> ESP)
Topic, yaitu alamat pengiriman data / tempat penyimpanan data yang dikirim.
Rangkaian:
A (LED) --> 22 (ESP32)
C (LED) --> GND (ESP32)
Note: Jangan lupa masukkan Library PubSubClient dan WiFi
ESP32 - PubSubClient.h
#include <WiFi.h>
#include <PubSubClient.h>
const char* ssid = "Wokwi-GUEST";
const char* password = "";
const char* mqtt_server = "mqtt-dashboard.com";
WiFiClient espClient;
PubSubClient client(espClient);
#define MSG_BUFFER_SIZE (50)
char msg[MSG_BUFFER_SIZE];
int led = 22;
void setup_wifi() {
WiFi.mode(WIFI_STA);
WiFi.begin(ssid, password);
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
randomSeed(micros());
Serial.println("WiFi Terhubung");
}
void callback(char* topic, byte* payload, unsigned int length) {
if ((char)payload[0] == '1') {
digitalWrite(led, 1);
client.publish("wokwi/led/status", "LED ON");
} else {
digitalWrite(led, 0);
client.publish("wokwi/led/status", "LED OFF");
}
}
void reconnect() {
while (!client.connected()) {
Serial.print("Menghubungkan ke MQTT");
String clientId = "BebasAja-";
clientId += String(random(0xffff), HEX);
if (client.connect(clientId.c_str())) {
Serial.println("MQTT Terhubung");
client.subscribe("wokwi/led/onOff");
} else {
Serial.print("failed, rc=");
Serial.print(client.state());
Serial.println("Coba ulang dalam 5 detik");
delay(5000);
}
}
}
void setup() {
pinMode(led, OUTPUT);
digitalWrite(led, LOW);
Serial.begin(115200);
setup_wifi();
client.setServer(mqtt_server, 1883);
client.setCallback(callback);
}
void loop() {
if (!client.connected()) {
reconnect();
}
client.loop();
}
Rangkaian:
A (LED) --> 22 (ESP32)
C (LED) --> GND (ESP32)
Note: Jangan lupa masukkan Library MQTT dan WiFi
ESP32 - MQTT.h
#include <WiFi.h>
#include <MQTT.h>
const char ssid[] = "Wokwi-GUEST";
const char pass[] = "";
WiFiClient net;
MQTTClient client;
int led = 22;
void connect() {
Serial.print("Menghubungkan ke WiFi...");
while (WiFi.status() != WL_CONNECTED) {
Serial.print(".");
delay(1000);
}
while (!client.connect("Bebas-Aja")) {
Serial.print(".");
delay(1000);
}
Serial.println("\nTerhubung ke MQTT");
client.subscribe("wokwi/led/onOff");
}
void messageReceived(String &topic, String &payload) {
Serial.println("incoming: " + topic + " - " + payload);
if (payload == "1"){
digitalWrite(led, HIGH);
client.publish("wokwi/led/status", "LED ON");
}
else {
digitalWrite(led, LOW);
client.publish("wokwi/led/status", "LED OFF");
}
}
void setup() {
Serial.begin(115200);
WiFi.begin(ssid, pass);
pinMode(led, OUTPUT);
digitalWrite(led, LOW);
client.begin("mqtt-dashboard.com", net);
client.onMessage(messageReceived);
connect();
}
void loop() {
client.loop();
delay(10);
if (!client.connected()) {
connect();
}
}