Toggle Led with cloudMqtt and Homeassistant and NodeMCU

amiroruji72 · October 18, 2017, 8:33pm

Hi Guys
I have created a mqtt switch in my home assistant panel and when i toggle the switch it sends messages to cloudmqtt properly.

But I want to send this messages to nodeMCU too and print it to serial monitor but i cant

   indent preformatted text by 4 spaces

#include “DHT.h”
#include <ESP8266WiFi.h>
#include <WiFiClient.h>
#include <PubSubClient.h>
#include <ArduinoJson.h>

float humidity, temp_f;
const char* ssid = “Amir”;
const char* password = “911183012”;
const char* mqtt_server = “m11.cloudmqtt.com”;
const int mqtt_server_port = 18749;
const char* mqtt_user = “switch1”;
const char* mqtt_password = “09393721211”;
int ledPin = 1;
String message="";
DHT dht2(2,DHT22);
WiFiClient wifiClient;

void callback(char* topic, byte* payload, unsigned int length)
{
Serial.print(“Message arrived [”);
Serial.print(topic);
Serial.print("] ");
for (int i=0;i<length;i++)
{
String receivedChar = (String)payload[i];
Serial.print(receivedChar);
if (receivedChar == “OFF”)
{
digitalWrite(ledPin, HIGH);
}
if (receivedChar == “ON”)
{
digitalWrite(ledPin, LOW);
}
}
Serial.println();
}

PubSubClient client(mqtt_server, mqtt_server_port,wifiClient );

void setup(void)
{
Serial.begin(115200);
WiFi.begin(ssid, password);
Serial.print("\n\r \n\rConnecting to ");
Serial.println(ssid);

client.setCallback(callback);
// Wait for connection
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
Serial.println("\n\rESP8266 & DHT22 based temperature and humidity sensor working!");
Serial.print("\n\rIP address: ");
Serial.println(WiFi.localIP());

while (!client.connected()) {
Serial.print("Attempting MQTT connection to “);
Serial.print(mqtt_server);
Serial.print(” ");

// Attempt to connect
if (client.connect(mqtt_server, mqtt_user, mqtt_password)) {
Serial.println(“connected”);
} else {
Serial.print(“failed, rc=”);
Serial.print(client.state());
Serial.println(" try again in 5 seconds");

// Wait 5 seconds before retrying
delay(5000);
}
}

}

void loop()
{

// temp_f = dht2.readTemperature();

// message = “{“temp”: “” + String((int)temp_f) + “”}”;

//Serial.println("Temperature in C:");
//Serial.println((dht2.readTemperature( )));
//Serial.println("Humidity :");
//Serial.println((dht2.readHumidity( )));
 
//client.publish("/dht", message.c_str());

client.loop();
}

Here is my code.

and I recieve the messages in the cloudmqtt like this pic.

The last one is for switch

gpbenton · October 18, 2017, 9:44pm

You need to get your esp8266 to subscribe to the topic being sent, so that the callback is called.
Try

 if (client.connect(mqtt_server, mqtt_user, mqtt_password)) {
  Serial.println(“connected”);
  client.subscribe("home1/bedroom/switch1/set");
}

amiroruji72 · October 19, 2017, 5:34am

Ok thanks a lot.
And another thing
Is the line
String receivedChar = (String)payload[i];
Correct ??

Because i want to define my payload as a string.
For example i have 2 switches and i want to set different payload on theme
Like switch1-on ,switch1-off ,switch2-on,switch2-off

But i dont know how should i do that

gpbenton · October 19, 2017, 8:19am

It looks like the for ... loop construct isn’t doing what you expect.

It is taking each character in turn from the payload and comparing it to a whole string.

I do this to convert my topic and payload to strings, which I undoubtedly copied from someone else

  // Allocate the correct amount of memory for the payload copy
  byte* p = (byte*)malloc(length);
  // Copy the payload to the new buffer
  memcpy(p,payload,length);
  
  // Conversion to a printable string
  p[length] = '\0';
  String payload_s = String((char *) p);
  String topicNameRec = String((char*) topic);
  
  // Process the message using `topicNameRec` and `payload_s`

  // Free the memory
  free(p);

amiroruji72 · October 19, 2017, 10:29am

Ok

Thanks a lot

I will check it.

amiroruji72 · October 20, 2017, 7:49pm

Hi again

I made some changes to my code but it doesn’t work again

indent preformatted text by 4 spaces

#include “DHT.h”
#include <ESP8266WiFi.h>
#include <WiFiClient.h>
#include <PubSubClient.h>
#include <ArduinoJson.h>

void callback(char* topic, byte* payload, unsigned int length);

const char* ssid = “***";
const char* password = "***";
const char mqtt_server = “m11.cloudmqtt.com”;
const int mqtt_server_port = ;
const char mqtt_user = “switch1”;
const char mqtt_password = "”;
const int switchPin1 = 5;

char const* switchTopic1 = “/house/switch1/”;

WiFiClient wifiClient;

PubSubClient client(mqtt_server, mqtt_server_port,callback,wifiClient);

void setup(void)
{
pinMode(switchPin1, OUTPUT);

digitalWrite(switchPin1, LOW);
Serial.begin(115200);
WiFi.begin(ssid, password);
Serial.print("\n\r \n\rConnecting to ");
Serial.println(ssid);

// Wait for connection
while (WiFi.status() != WL_CONNECTED) {
delay(500);
Serial.print(".");
}
Serial.println("\n\rESP8266 & DHT22 based temperature and humidity sensor working!");
Serial.print("\n\rIP address: ");
Serial.println(WiFi.localIP());

while (!client.connected()) {
Serial.print("Attempting MQTT connection to “);
Serial.print(mqtt_server);
Serial.print(” ");

// Attempt to connect
if (client.connect(mqtt_server, mqtt_user, mqtt_password)) {
Serial.println(“connected”);
client.subscribe(switchTopic1);
} else {
Serial.print(“failed, rc=”);
Serial.print(client.state());
Serial.println(" try again in 5 seconds");

// Wait 5 seconds before retrying
delay(5000);
}
}

}

void loop()
{
client.loop();
}

void callback(char* topic, byte* payload, unsigned int length) {
String topicStr = topic;
Serial.println(“Callback update.”);
Serial.print("Topic: ");
Serial.println(topicStr);
if (topicStr == “/house/switch1/”)
{

if(payload[0] == '1'){  
  
 digitalWrite(switchPin1, HIGH);  
       
 client.publish("/house/switchConfirm1/", "1");  
 delay(700);  
 }  

 
  
else if (payload[0] == '0'){  
  
 digitalWrite(switchPin1, LOW);  
       
 client.publish("/house/switchConfirm1/", "0");  
   
 }  
 } 
}  
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and i write these things in my configuration.yaml file:

switch 1:

platform: mqtt
name: “Wall Light”
state_topic: “/house/switchConfirm1/”
command_topic: “/house/switch1/”
payload_on: “1”
payload_off: “0”
qos: 0
retain: true

and i see in the serial monitor and my cloud mqqt logs that messages send and receive successfully but the LED didn’t turn on/off.

I dont know where is the problem???

gpbenton · October 20, 2017, 7:58pm

Can you see if this is getting sent? If so, the problem is with the digitalWrite() or the hardware, and I can’t help much with that.

amiroruji72 · October 20, 2017, 8:10pm

Yes I see this