diff --git a/src/cpp/sensor_monitor/esp32/main/network.c b/src/cpp/sensor_monitor/esp32/main/network.c
index c41f3a6d9..8610395c0 100644
--- a/src/cpp/sensor_monitor/esp32/main/network.c
+++ b/src/cpp/sensor_monitor/esp32/main/network.c
@@ -3,9 +3,6 @@
 static TaskHandle_t task = NULL;
 static void networking(void *p) {
     char *payload = "ping               \n";
-
-  
-    double* data;
     for (;;) {
       
       mqtt_write(payload, "ping");
@@ -51,6 +48,7 @@ static void status_callback(esp_mqtt_status_t status) {
     switch (status) {
       case ESP_MQTT_STATUS_CONNECTED:
         esp_mqtt_subscribe("test", 0);
+        esp_mqtt_subscribe("ping", 0);
         xTaskCreatePinnedToCore(networking, "networking", 4096, NULL, 10, &task, 1);
         break;
       case ESP_MQTT_STATUS_DISCONNECTED:
@@ -60,7 +58,7 @@ static void status_callback(esp_mqtt_status_t status) {
   }
   
 static void message_callback(const char *topic, uint8_t *payload, size_t len) {
-    //printf("incoming: %s => %s (%d)\n", topic, payload, (int)len);
+    printf("incoming: %s => %s (%d)\n", topic, payload, (int)len);
   }
 
 static esp_err_t event_handler(void *ctx, system_event_t *event) {
diff --git a/src/cpp/sensor_monitor/esp32/main/network.h b/src/cpp/sensor_monitor/esp32/main/network.h
index 08568e090..0f72df6b8 100644
--- a/src/cpp/sensor_monitor/esp32/main/network.h
+++ b/src/cpp/sensor_monitor/esp32/main/network.h
@@ -4,10 +4,10 @@
 #include <esp_mqtt.h>
 #include <esp_wifi.h>
 
-#define WIFI_SSID "Router"
-#define WIFI_PASS "19670227"
+#define WIFI_SSID "SSID"
+#define WIFI_PASS "PASS"
 
-#define MQTT_HOST "192.168.1.105"
+#define MQTT_HOST "HOST"
 #define MQTT_PORT 1883
 #define MQTT_USER ""
 #define MQTT_PASS ""
diff --git a/src/cpp/sensor_monitor/esp32/main/sensor.c b/src/cpp/sensor_monitor/esp32/main/sensor.c
index 426eab01e..45f09e337 100644
--- a/src/cpp/sensor_monitor/esp32/main/sensor.c
+++ b/src/cpp/sensor_monitor/esp32/main/sensor.c
@@ -10,12 +10,6 @@ static void IRAM_ATTR gpio_isr_handler(void* arg)
     xQueueSendFromISR(gpio_evt_queue, &gpio_num, NULL);
 }
 
-typedef struct sens sens;
-
-struct sens{
-    uint64_t d_time;
-    uint64_t f_time;
-};
 uint64_t * carriages; // 00000000 00000000 00000000 00000000 00000000 00000000 00000000 00000000
                       // |=========1. sensor times=========| |=========0. sensor times=========|
                       // |t__out| |t__out| |tstart| |tstart| |t__out| |t__out| |tstart| |tstart|
@@ -36,7 +30,7 @@ void calculate(uint64_t *carriage){
     char* payload = (char*)malloc(sizeof(char)*50);
     double speed = ((double)SENSOR_DISTANCE) * 100 /dt;
     double length = speed * t_block / 100;
-    sprintf(payload, "speed: %010.3lfcm/s length: %010.3lfcm\n", speed, length);
+    sprintf(payload, "speed: %010.3lfcm/s length: %010.3lfcm\n", speed, length); 
     mqtt_write(payload, "test");
 }
 
@@ -51,7 +45,6 @@ static void sensor() {
 
     carriages = (uint64_t*)malloc(sizeof(uint64_t)*5);
     for(int i = 0; i<5; i++)carriages[i] = 0;
-    uint8_t a = 0;
     uint8_t i = 0;
     
     while (1){
@@ -63,21 +56,13 @@ static void sensor() {
                 switch(level[id] - last_level[id]){
                     case -1: //LOW vezérlés esetén jön a vonat
                         i = 0;
-                        while(carriages[i] & ((uint64_t)(0b1111111111111111)<<(2*id*16))) {
-                            
-                            i++;
-                        
-                        }
-                       
-                        carriages[i] |= (uint64_t)((uint16_t)(clock() * 100 / CLOCKS_PER_SEC)) << (2*id*16);
+                        while(carriages[i] & ((uint64_t)((1<<16) - 1)<<(2*id*16))) i++;
+                        carriages[i] |= ((uint64_t)(clock() * 100 / CLOCKS_PER_SEC)) << (2*id*16); //shifting the current time (on 16 bits) to its correct place (in 'centiseconds') -> max is reached after cca 10 minutes
                         break;
                     case 1:
                         i = 0;
-                        while(carriages[i] & ((uint64_t)(0b1111111111111111)<<((2*id+1)*16))) {
-                           
-                            i++;
-                        }
-                        carriages[i] |= (uint64_t)((uint64_t)(clock() * 100 / CLOCKS_PER_SEC - (uint64_t)((carriages[i] & ((uint64_t)0b1111111111111111<<(2*id*16)))>>(2*id*16)))) << ((2*id+1)*16);
+                        while(carriages[i] & ((uint64_t)((1<<16) - 1)<<((2*id+1)*16))) i++;
+                        carriages[i] |= ((uint64_t)(clock() * 100 / CLOCKS_PER_SEC - (uint64_t)((carriages[i] & ((uint64_t)((1<<16) - 1)<<(2*id*16)))>>(2*id*16)))) << ((2*id+1)*16); //shifting the time difference (on 16 bits) to its correct place
                         if(is_full(carriages[i])) calculate(&(carriages[i]));
                         break;
                     default:
@@ -85,7 +70,6 @@ static void sensor() {
                 }
                 time[id] = clock();
                 last_level[id] = level[id];
-                 
             }
             
         }
diff --git a/src/cpp/sensor_monitor/esp32/main/sensor.h b/src/cpp/sensor_monitor/esp32/main/sensor.h
index 1fc48130f..52dc02726 100644
--- a/src/cpp/sensor_monitor/esp32/main/sensor.h
+++ b/src/cpp/sensor_monitor/esp32/main/sensor.h
@@ -13,8 +13,8 @@
 #define GPIO_INPUT_IO_1     27
 #define GPIO_INPUT_PIN_SEL  ((1<<GPIO_INPUT_IO_0) | (1<<GPIO_INPUT_IO_1))
 #define ESP_INTR_FLAG_DEFAULT 0
-#define EPS 10
-#define EPS_MEASURE 200
+#define EPS 20
+#define EPS_MEASURE 20
 #define SENSOR_DISTANCE 7
 
 static void IRAM_ATTR gpio_isr_handler(void*);