       app_key_offset++;
 #endif
 
-      // Get measures
+//----------------------- let's make the message ---------------------------------
+      String messageToSend;
+      //header
+      messageToSend = String("ST:"+station_number);
+
+// add sensor's measures
+#ifdef SENSOR_HCS
       // Proximity sensor
       myProximitySensor.measure();
-      //long proximityDistance = myProximitySensor.getCm();
       String proximityDist = String(myProximitySensor.getCm(),DEC);
-      //ltoa(proximityDistance,proximityDist,10);
-
+      messageToSend = String(messageToSend + ";WL:" + proximityDist);
+#endif
+
+#ifdef SENSOR_DHT
       // DHT sensor
-      delay(myDhtSensor.getMinimumSamplingPeriod());
+      //delay(myDhtSensor.getMinimumSamplingPeriod());
       float humidity = myDhtSensor.getHumidity();
       float temperature = myDhtSensor.getTemperature();
       String dhtTemperature = String(temperature);
       String dhtHumidity = String(humidity);
-
-      
-      
+      messageToSend = String(messageToSend + ";TE:" + dhtTemperature + ";AH:" + dhtHumidity);
+#endif
+
+#ifdef SENSOR_OZONE
+      // MQ-131 Ozone sensor
+      int mq_value = analogRead(ozone_value_pin);
+      String mqOzoneValue = String(mq_value,DEC);
+      messageToSend = String(messageToSend + ";OZ:" + mqOzoneValue);
+#endif
+
       uint8_t r_size;
-
-      char float_rand[3];
-      
-      String messageToSend;
-      messageToSend = String("PR:" + probe_number + ";" + "WL:" + proximityDist + ";" + "TE:" + dhtTemperature + ";" + "AH:" + dhtHumidity);
-      //"OZ:99.9;TE:99.9;AH:24.8;GH:33.6;WL:22.4;WT:");
+      // format of the message
+      //"PR:1;OZ:99.9;TE:99.9;AH:24.8;GH:33.6;WL:22.4;WT:18.4"
       messageToSend.toCharArray(float_str,NB_MESSAGE_LENGTH);
-      //ftoa(float_str,temp,2);
-      int valueRand = rand();
-      //itoa(valueRand,float_rand,3);
-      //strcpy(float_str,"PR:1;OZ:20.4;TE:12.6;AH:24.8;GH:33.6;WL:22.4;WT:18.4");
-      //strcpy(float_str,"PR:1;OZ:20.4;TE:12.6;AH:24.8;GH:33.6;WL:22.4;WT:");
-      strncat(float_str,float_rand,4);
       r_size=sprintf((char*)message+app_key_offset, "\\!#%d#%s", field_index, float_str);
 
       Serial.print(F("Sending "));

//#define BAND900
///////////////////////////////////////////////////////////////////////////////////////////////////////////

#include <HCSR04.h>
#include <DHT.h>

#define WITH_EEPROM
#define WITH_APPKEY

//#define WITH_AES

#define DEFAULT_DEST_ADDR 1
#define LORAMODE  3
#define node_addr 6
#define field_index 3
//#define node_addr 10
