Belajar Pertanian - mqtt-led-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();

}