diff --git a/extras/sht3x/sht3x.c b/extras/sht3x/sht3x.c
index 0d8787e..f01bbdf 100644
--- a/extras/sht3x/sht3x.c
+++ b/extras/sht3x/sht3x.c
@@ -3,7 +3,6 @@
 #include "sht3x.h"
 
 #include "FreeRTOS.h"
-#include "queue.h"
 #include "task.h"
 
 #include "espressif/esp_common.h"
@@ -121,8 +120,8 @@ static void sht3x_compute_values (uint8_t id, uint8_t* data)
   sht3x_value_set_t  avg = sht3x_sensors[id].average;
   float w = sht3x_sensors[id].average_weight;
 
-  act.c_temperature = ((((data[0] * 256.0) + data[1]) * 175) / 65535.0) - 45;
-  act.f_temperature = ((((data[0] * 256.0) + data[1]) * 347) / 65535.0) - 49;
+  act.temperature_c = ((((data[0] * 256.0) + data[1]) * 175) / 65535.0) - 45;
+  act.temperature_f = ((((data[0] * 256.0) + data[1]) * 347) / 65535.0) - 49;
   act.humidity      = ((((data[3] * 256.0) + data[4]) * 100) / 65535.0);
   
   if (sht3x_sensors[id].first_measurement)
@@ -133,8 +132,8 @@ static void sht3x_compute_values (uint8_t id, uint8_t* data)
   }
   else
   {
-    avg.c_temperature = w * act.c_temperature + (1-w) * avg.c_temperature;
-    avg.f_temperature = w * act.f_temperature + (1-w) * avg.f_temperature;
+    avg.temperature_c = w * act.temperature_c + (1-w) * avg.temperature_c;
+    avg.temperature_f = w * act.temperature_f + (1-w) * avg.temperature_f;
     avg.humidity      = w * act.humidity      + (1-w) * avg.humidity;
   }
    
@@ -161,8 +160,8 @@ static void sht3x_callback_task (void *pvParameters)
                 sht3x_compute_values(sensor, data);
                 
                 // DEBUG_PRINTF3("%.2f C, %.2f F, %.2f \n", 
-                //               sht3x_sensors[sensor].actual.c_temperature,
-                //               sht3x_sensors[sensor].actual.f_temperature,
+                //               sht3x_sensors[sensor].actual.temperature_c,
+                //               sht3x_sensors[sensor].actual.temperature_f,
                 //               sht3x_sensors[sensor].actual.humidity);
 
                 if (sht3x_sensors[sensor].cb_function)
@@ -292,8 +291,8 @@ bool sht3x_get_values(uint32_t sensor, sht3x_value_set_t *actual, sht3x_value_se
     if (!sht3x_valid_sensor(sensor, __FUNCTION__))
         return false;
 
-    *actual  = sht3x_sensors[sensor].actual;
-    *average = sht3x_sensors[sensor].average;
+    if (actual)  *actual  = sht3x_sensors[sensor].actual;
+    if (average) *average = sht3x_sensors[sensor].average;
 
     return true;
 }
diff --git a/extras/sht3x/sht3x.h b/extras/sht3x/sht3x.h
index fbfa7ea..0cd04c1 100644
--- a/extras/sht3x/sht3x.h
+++ b/extras/sht3x/sht3x.h
@@ -19,7 +19,7 @@
 #include "i2c/i2c.h"
 
 // Uncomment to enable debug output
-#define SHT3x_DEBUG
+// #define SHT3x_DEBUG
 
 // Change this if you need more than 3 SHT3x sensors
 #define SHT3x_MAX_SENSORS 3
@@ -29,9 +29,9 @@ extern "C" {
 #endif
 
 typedef struct {
-    float   c_temperature;
-    float   f_temperature;
-    float   humidity;
+    float   temperature_c;    // temperature in degree Fahrenheit
+    float   temperature_f;    // temperature in degree Celcius
+    float   humidity;         // humidity in percent
 } sht3x_value_set_t;
 
 typedef void (*sht3x_cb_function_t)(uint32_t sensor,
@@ -72,10 +72,10 @@ bool sht3x_init ();
 /**
  * Initialize the SHT3x sensor connected to a certain bus with slave
  * address, check its availability and start a background task for
- * measurments.
+ * measurements.
  * 
  * The background task carries out measurements periodically using SHT3x's
- * single shot data aquisition mode with a default period of 1000 ms.
+ * single shot data acquisition mode with a default period of 1000 ms.
  * This period be changed using function @set_measurment_period.
  * 
  * At each measurement, actual sensor values are determined and exponential
@@ -139,7 +139,10 @@ bool sht3x_delete_sensor (uint32_t sensor);
 
 
 /**
- * Returns actual and average sensor values of last measurement. 
+ * Returns actual and average sensor values of last measurement. Parameters
+ * @actual and @average are pointer to data structures of type
+ * @sht3x_value_set_t which are filled with measurement results. Use NULL for
+ * that pointers parameters, if you are not interested on certain results. 
  *
  * This function is only needed, if there is no callback function registered
  * for the sensor.
@@ -156,8 +159,8 @@ bool sht3x_get_values (uint32_t sensor,
 
 /**
  * At each measurement carried out by the background task, actual
- * sensor values are determined and exponential moving avarage values are
- * computed accoroding to following equation
+ * sensor values are determined and exponential moving average values are
+ * computed according to following equation
  *
  *    Average[k] = W * Value + (1-W) * Average [k-1]
  *