diff --git a/arduino/MQTT/MQTT.ino b/arduino/MQTT/MQTT.ino
index 575e917..e33233c 100644
--- a/arduino/MQTT/MQTT.ino
+++ b/arduino/MQTT/MQTT.ino
@@ -9,62 +9,33 @@
 #define CERT mqtt_broker_cert
 #define MSG_BUFFER_SIZE (50)
 
-//--------------------------------------
-// config (edit here before compiling)
-//--------------------------------------
-// #define MQTT_TLS // uncomment this define to enable TLS transport
-// #define MQTT_TLS_VERIFY // uncomment this define to enable broker certificate verification
+
 const char* ssid = VITRINE_SSID;
 const char* password = VITRINE_WIFI_PASS;
-const char* mqtt_server = "mqtt.klank.school"; // eg. your-demo.cedalo.cloud or 192.168.1.11
-const uint16_t mqtt_server_port = 7000; // or 8883 most common for tls transport
+const char* mqtt_server = "mqtt.klank.school";  // eg. your-demo.cedalo.cloud or 192.168.1.11
+const uint16_t mqtt_server_port = 7000;         // or 8883 most common for tls transport
 const char* mqttUser = MQTT_ARDUINO_USERNAME;
 const char* mqttPassword = MQTT_ARDUINO_PASS;
-const char* mqttTopicIn = "esp-8266-in";
-const char* mqttTopicOut = "esp-8266-out";
+
+bool isOn = false;
+
+#define MAIN_CHANNEL "main"
 
 
-const char* rootCACertificate = R"(
------BEGIN CERTIFICATE-----
-MIIDvTCCAqWgAwIBAgIUIjMIFwrRWBr9z0lTWa7CQ0GcKV0wDQYJKoZIhvcNAQEL
-BQAwdDELMAkGA1UEBhMCTkwxFTATBgNVBAgMDFp1aWQtSG9sbGFuZDESMBAGA1UE
-BwwJUm90dGVyZGFtMRQwEgYDVQQKDAtLbGFua3NjaG9vbDENMAsGA1UECwwETVFU
-VDEVMBMGA1UEAwwMa2xhbmsuc2Nob29sMB4XDTI0MTAyODExMjUwMFoXDTI1MTAy
-ODExMjUwMFoweTELMAkGA1UEBhMCTkwxFTATBgNVBAgMDFp1aWQtSG9sbGFuZDES
-MBAGA1UEBwwJUm90dGVyZGFtMRQwEgYDVQQKDAtLbGFua3NjaG9vbDENMAsGA1UE
-CwwETVFUVDEaMBgGA1UEAwwRbXF0dC5rbGFuay5zY2hvb2wwggEiMA0GCSqGSIb3
-DQEBAQUAA4IBDwAwggEKAoIBAQDHiV7tLQdZg9qztSXYujw1dqL9lpqy5nDCkm8/
-Sd9wOh6SBMm65LvcJb3YBpoPfI6hwwOI+XcWsGiTTuOiCM3EemVYXkcc0VCjbgzn
-FZ3Ld4s1jpXy+EgDaNhXXfFpREzStDOcRrmnIm5iHRiKdWAWeJTmYas915jzTCrk
-ibhW9Qd9WZstxdccpjBWnB4X6uSMOeGdunAifTY8vVLQtaBlAqyoPbZk1ELbqKaz
-zBso34euvKoPCPs8nkFR/RpLNStuOTVC8g+uCQ8nIgNlXpftvjMHvBsoq7ZdICRI
-jx9uW4U0y2kEF7d3P9eLl07uJjxHhurB/J/kJHm5qc4tVcOXAgMBAAGjQjBAMB0G
-A1UdDgQWBBRjQ4b5y5mEeidokSMz0pRetgNuRTAfBgNVHSMEGDAWgBR0e8d1l8aw
-EGSdl1/vBUgQcmlV7jANBgkqhkiG9w0BAQsFAAOCAQEAaK8rrSeqLJIAr3v+GAdJ
-yGqWK9qpJgXEbxYiuIj0pSejpDX3609qvyy7YEDUqLTu44ulZmrgGfrWAXg6Boms
-CpBGybNNd7oYhcGJdSCURt2EgjkEP0eCVXo02l4JDrnaNvsBt9OhEVvNSFRxblyE
-UmUTWeMh27T1/ioHeQpLIBf2BPOJZrMGeQGNfYujbtd8F4VQmGcOcfGsPhbvsaFR
-dUut/VtKBnifKmZ/6afbmHHBUW6IjxTXBm8J0PrY9H5SR/Y7hEvbshlETFO5djMZ
-6mmitx2Bxd2s9/nPWPXk5YZryCvWvEHof23dE81OfVLaGYGdzL4ys5UiEWd/X8jP
-1Q==
------END CERTIFICATE-----
-)";
-
+#define RELAY_1 1
 //--------------------------------------
 // globals
 //--------------------------------------
 #ifdef MQTT_TLS
-  WiFiClientSecure wifiClient;
+WiFiClientSecure wifiClient;
 #else
-  WiFiClient wifiClient;
+WiFiClient wifiClient;
 #endif
 WiFiUDP ntpUDP;
 NTPClient timeClient(ntpUDP);
 PubSubClient mqttClient(wifiClient);
 
-//--------------------------------------
-// function setup_wifi called once
-//--------------------------------------
+
 void setup_wifi() {
 
   delay(10);
@@ -73,31 +44,17 @@ void setup_wifi() {
   Serial.println(ssid);
 
   WiFi.begin(ssid, password);
-
+  Serial.println("start while");
   while (WiFi.status() != WL_CONNECTED) {
-    delay(500);
+    delay(50);
     Serial.print(".");
   }
+  Serial.println("i am here 1");
   timeClient.begin();
 
-#ifdef MQTT_TLS
-  #ifdef MQTT_TLS_VERIFY
-    // X509List *cert = new X509List(CERT);
-    // wifiClient.setTrustAnchors(cert);
-      wifiClient.setTrustAnchors(new BearSSL::X509List(rootCACertificate));
-
-  #else
-    wifiClient.setInsecure();
-  #endif
-#endif
-
   Serial.println("WiFi connected");
 }
 
-//--------------------------------------
-// function callback called everytime 
-// if a mqtt message arrives from the broker
-//--------------------------------------
 void callback(char* topic, byte* payload, unsigned int length) {
   Serial.print("Message arrived on topic: '");
   Serial.print(topic);
@@ -105,29 +62,28 @@ void callback(char* topic, byte* payload, unsigned int length) {
   for (unsigned int i = 0; i < length; i++) {
     Serial.print((char)payload[i]);
   }
-  Serial.println();
 
-  String myCurrentTime = timeClient.getFormattedTime();
-  mqttClient.publish(mqttTopicOut,("ESP8266: Cedalo Mosquitto is awesome. ESP8266-Time: " + myCurrentTime).c_str());
+  if (isOn) {
+    digitalWrite(RELAY_1, HIGH);
+    isOn = false;
+  } else {
+    digitalWrite(RELAY_1, LOW);
+    isOn = true;
+  }
+  Serial.println();
 }
 
-//--------------------------------------
-// function connect called to (re)connect
-// to the broker
-//--------------------------------------
+
 void connect() {
   while (!mqttClient.connected()) {
 
-    // Serial.println("The last error was");
-    // Serial.println(wifiClient.getLastSSLError(NULL));
-
-
     Serial.print("Attempting MQTT connection...");
     String clientId = "ESP8266Client-";
     clientId += String(random(0xffff), HEX);
     if (mqttClient.connect(clientId.c_str(), mqttUser, mqttPassword)) {
       Serial.println("connected");
-      mqttClient.subscribe(mqttTopicIn);
+      mqttClient.subscribe(MAIN_CHANNEL);
+      mqttClient.publish(MAIN_CHANNEL, ("Whaddup can i stay? "));
     } else {
       Serial.print("failed, rc=");
       Serial.print(mqttClient.state());
@@ -137,24 +93,24 @@ void connect() {
   }
 }
 
-//--------------------------------------
-// main arduino setup fuction called once
-//--------------------------------------
+
+
 void setup() {
-  Serial.begin(115200);
+  Serial.begin(9600);
+  Serial.println("run setup");
   setup_wifi();
+  Serial.println("finish setup_wifi");
+  pinMode(RELAY_1, OUTPUT);
+
   mqttClient.setServer(mqtt_server, mqtt_server_port);
   mqttClient.setCallback(callback);
 }
 
-//--------------------------------------
-// main arduino loop fuction called periodically
-//--------------------------------------
 void loop() {
   if (!mqttClient.connected()) {
     connect();
   }
- 
+
   mqttClient.loop();
   timeClient.update();
 }