diff --git a/Adafruit_BME280.h b/Adafruit_BME280.h
index db88379..4f8cd0f 100644
--- a/Adafruit_BME280.h
+++ b/Adafruit_BME280.h
@@ -138,11 +138,11 @@ class Adafruit_BME280_Unified : public Adafruit_Sensor
 /**************************************************************************/
 class Adafruit_BME280 {
     public:
-    /**************************************************************************/
-    /*! 
-        @brief  sampling rates
-    */
-    /**************************************************************************/
+        /**************************************************************************/
+        /*! 
+            @brief  sampling rates
+        */
+        /**************************************************************************/
         enum sensor_sampling {
             SAMPLING_NONE = 0b000,
             SAMPLING_X1   = 0b001,
@@ -220,9 +220,9 @@ class Adafruit_BME280 {
         float seaLevelForAltitude(float altitude, float pressure);
 
         
-    private:
-		TwoWire *_wire;
-        void readCoefficients(void);
+    protected:
+		TwoWire *_wire; //!< pointer to a TwoWire object
+        void readCoefficients(void); 
         bool isReadingCalibration(void);
         uint8_t spixfer(uint8_t x);
 
@@ -234,15 +234,23 @@ class Adafruit_BME280 {
         uint16_t  read16_LE(byte reg); // little endian
         int16_t   readS16_LE(byte reg); // little endian
 
-        uint8_t   _i2caddr;
-        int32_t   _sensorID;
-        int32_t   t_fine;
+        uint8_t   _i2caddr; //!< I2C addr for the TwoWire interface
+        int32_t   _sensorID; //!< ID of the BME Sensor
+        int32_t   t_fine; //!< temperature with high resolution, stored as an attribute as this is used for temperature compensation reading humidity and pressure
 
-        int8_t _cs, _mosi, _miso, _sck;
+        int8_t _cs;   //!< for the SPI interface
+        int8_t _mosi; //!< for the SPI interface
+        int8_t _miso; //!< for the SPI interface
+        int8_t _sck;  //!< for the SPI interface
 
-        bme280_calib_data _bme280_calib;
+        bme280_calib_data _bme280_calib; //!< here calibration data is stored
 
-        // The config register
+
+        /**************************************************************************/
+        /*! 
+            @brief  config register
+        */
+        /**************************************************************************/                
         struct config {
             // inactive duration (standby time) in normal mode
             // 000 = 0.5 ms
@@ -253,7 +261,7 @@ class Adafruit_BME280 {
             // 101 = 1000 ms
             // 110 = 10 ms
             // 111 = 20 ms
-            unsigned int t_sb : 3;
+            unsigned int t_sb : 3; ///< inactive duration (standby time) in normal mode
 
             // filter settings
             // 000 = filter off
@@ -261,20 +269,25 @@ class Adafruit_BME280 {
             // 010 = 4x filter
             // 011 = 8x filter
             // 100 and above = 16x filter
-            unsigned int filter : 3;
+            unsigned int filter : 3; ///< filter settings
 
             // unused - don't set
-            unsigned int none : 1;
-            unsigned int spi3w_en : 1;
+            unsigned int none : 1;  ///< unused - don't set
+            unsigned int spi3w_en : 1; ///< unused - don't set
 
+            /// @return combined config register
             unsigned int get() {
                 return (t_sb << 5) | (filter << 2) | spi3w_en;
             }
         };
-        config _configReg;
+        config _configReg; //!< config register object
 
         
-        // The ctrl_meas register
+        /**************************************************************************/
+        /*! 
+            @brief  ctrl_meas register
+        */
+        /**************************************************************************/                
         struct ctrl_meas {
             // temperature oversampling
             // 000 = skipped
@@ -283,7 +296,7 @@ class Adafruit_BME280 {
             // 011 = x4
             // 100 = x8
             // 101 and above = x16
-            unsigned int osrs_t : 3;
+            unsigned int osrs_t : 3; ///< temperature oversampling
 
             // pressure oversampling
             // 000 = skipped
@@ -292,24 +305,29 @@ class Adafruit_BME280 {
             // 011 = x4
             // 100 = x8
             // 101 and above = x16
-            unsigned int osrs_p : 3;
+            unsigned int osrs_p : 3; ///< pressure oversampling
 
             // device mode
             // 00       = sleep
             // 01 or 10 = forced
             // 11       = normal
-            unsigned int mode : 2;
+            unsigned int mode : 2; ///< device mode
 
+            /// @return combined ctrl register
             unsigned int get() {
                 return (osrs_t << 5) | (osrs_p << 2) | mode;
             }
         };
-        ctrl_meas _measReg;
+        ctrl_meas _measReg; //!< measurement register object
 
         
-        // The ctrl_hum register
+        /**************************************************************************/
+        /*! 
+            @brief  ctrl_hum register
+        */
+        /**************************************************************************/        
         struct ctrl_hum {
-            // unused - don't set
+            /// unused - don't set
             unsigned int none : 5;
 
             // pressure oversampling
@@ -319,13 +337,14 @@ class Adafruit_BME280 {
             // 011 = x4
             // 100 = x8
             // 101 and above = x16
-            unsigned int osrs_h : 3;
+            unsigned int osrs_h : 3; ///< pressure oversampling
 
+            /// @return combined ctrl hum register
             unsigned int get() {
                 return (osrs_h);
             }
         };
-        ctrl_hum _humReg;
+        ctrl_hum _humReg; //!< hum register object
 };
 
 #endif