ESP8266 MQTT client über access Point

#include <ESP8266WiFi.h>

#include <PubSubClient.h>

// Update these with values suitable for your network.

//const char* ssid = "........";

//const char* password = "........";

//const char* ssid = ".......";

//const char* password = "........"; 

//const char* ssid = "....."; //replace this with your WiFi network name

//const char* password = "......"; //replace this with your WiFi network password

const char* ssid = "......";

const char* password = "......"; 

const char* mqtt_server = "192.xxx.xxx.xxx";

WiFiClient espClient;

PubSubClient client(espClient);

long lastMsg = 0;

char msg[50];

int value = 0;

void setup_wifi() 

{

  delay(10);

  // We start by connecting to a WiFi network

  Serial.println();

  Serial.print("Connecting to ");

  Serial.println(ssid);

  WiFi.begin(ssid, password);

  while (WiFi.status() != WL_CONNECTED) 

  {

    delay(500);

    Serial.print(".");

  }

  randomSeed(micros());

  Serial.println("");

  /***********************************************/

  Serial.println("Connected.");

  Serial.print("MAC: ");

  Serial.println(WiFi.macAddress());

  Serial.print("IP:  ");

  Serial.println(WiFi.localIP());

  Serial.print("Subnet: ");

  Serial.println(WiFi.subnetMask());

  Serial.print("Gateway :");

  Serial.println(WiFi.gatewayIP());

  Serial.print("DNS: ");

  Serial.println(WiFi.dnsIP());

  Serial.print("Channel: ");

  Serial.println(WiFi.channel());

  Serial.print("Status: ");

  Serial.println(WiFi.status());

/***********************************************/ 

}

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++) 

  {

    Serial.print((char)payload[i]);

  }

  Serial.println();

  // Switch on the LED if an 1 was received as first character

  if ((char)payload[0] == '1') 

  {

    digitalWrite(2, LOW);   // Turn the LED on (Note that LOW is the voltage level

    // but actually the LED is on; this is because

    // it is acive low on the ESP-01)

  } else 

  {

    digitalWrite(2, HIGH);  // Turn the LED off by making the voltage HIGH

  }

}

void reconnect() 

{

  // Loop until we're reconnected

  while (!client.connected())

  {

    Serial.print("Attempting MQTT connection...");

    // Create a random client ID

    String clientId = "ESP8266Client-";

    clientId += String(random(0xffff), HEX);

    // Attempt to connect

    if (client.connect(clientId.c_str(),"openhabian","mqtt")) 

    {

      Serial.println("connected");

      // Once connected, publish an announcement...

      client.publish("outTopic", "hello world");

      // ... and resubscribe

      client.subscribe("inTopic");

    } 

    else 

    {

      Serial.print("failed, rc=");

      Serial.print(client.state());

      Serial.println(" try again in 5 seconds");

      // Wait 5 seconds before retrying

      delay(5000);

    }

  }

}

void setup() 

{

  pinMode(2, OUTPUT);     // Initialize the BUILTIN_LED pin as an output

  Serial.begin(115200);

  setup_wifi();

  client.setServer(mqtt_server, 1883);

  client.setCallback(callback);

}

void loop() 

{

  if (!client.connected()) 

  {

    reconnect();

  }

  client.loop();

  long now = millis();

  if (now - lastMsg > 2000) 

  {

    lastMsg = now;

    ++value;

    snprintf (msg, 75, "hello world #%ld", value);

    Serial.print("Publish message: ");

    Serial.println(msg);

    client.publish("outTopic", msg);

  }

}

Das Netzwerk ist so aufgebaut:

          ,- PC1

Fritzbox -|- Pc2

          '- TP Link Nano(als Access Point)--> ESP8266

          '- RaspberryPi(Mqtt Server)