mqtt, esp8266, pin control

ESP8266 Mqtt Pin Control

#include <PubSubClient.h>
#include <ESP8266WiFi.h>

#define MQTT_SERVER "192.168.1.2" // change the mqttbroker address
const char* ssid = "xxxxx"; // your wi-fi name
const char* password = "xxxxx"; // your wi-fi password
const int pin = 0; // in basic esp-01 you can control pin-0 and pin-2
char* clientname = "newesp"; // the mqtt client adress must be unique more than one esp usage
char* sublight = "/test/light"; // the mqtt sub adress
char* publight = "/test/light/confirm";  // the mqtt pub adress


WiFiClient wifiClient;
PubSubClient client(MQTT_SERVER, 1883, callback, wifiClient);

void setup() {
  pinMode(pin, OUTPUT);
  Serial.begin(115200);
  delay(100);
  WiFi.begin(ssid, password);
  if(WiFi.status() != WL_CONNECTED){
    while (WiFi.status() != WL_CONNECTED) {
      delay(500);
    }
  }
}

void loop(){
  if (!client.connected()) {
    while (!client.connected()) {
      if (client.connect(clientname)) {
        client.subscribe(sublight); // take commands
      }
      else{delay(500)}
    }
    }
  client.loop();
  delay(10);
}


//MQTT callback
void callback(char* topic, byte* payload, unsigned int length) {
  if(payload[0] == '1'){
    digitalWrite(pin, HIGH);
    client.publish(publight, "1"); // publish the new status
  }
  else{
    digitalWrite(pin, LOW);
    client.publish(publight, "0");  // publish the new status
  }
}