diff --git a/src/MQUnifiedsensor.cpp b/src/MQUnifiedsensor.cpp
index 5ee921a..0e33764 100644
--- a/src/MQUnifiedsensor.cpp
+++ b/src/MQUnifiedsensor.cpp
@@ -1,6 +1,5 @@
 #include "MQUnifiedsensor.h"
 
-
  MQUnifiedsensor::MQUnifiedsensor(int pin, int type) {
 
   this->_pin = pin;
@@ -67,11 +66,10 @@
     //_MQ = MQ309;
   }
 }
-
-void MQUnifiedsensor::setR0(double R0) {
-  this->_R0 = R0;
+void MQUnifiedsensor::inicializar()
+{
+  pinMode(_pin, INPUT);
 }
-
 int MQUnifiedsensor::readSensor(String nameLectureRequeired, bool print)
 {
   setSensorCharacteristics(nameLectureRequeired);
@@ -87,78 +85,92 @@ int MQUnifiedsensor::readSensor(String nameLectureRequeired, bool print)
   }
   return _PPM;
 }
-void MQUnifiedsensor::inicializar()
+String MQUnifiedsensor::getnameLecture()
 {
-  pinMode(_pin, INPUT);
+  return nameLecture[_lecturePosInArray];
 }
 void MQUnifiedsensor::setSensorCharacteristics(String nameLectureRequeired)
 {
-  int wantedpos = 0;
   if(nameLectureRequeired == "")
   {
     if(_type == 2)
     {
-      wantedpos = defaultMQ2;
+      _lecturePosInArray = defaultMQ2;
     }
     else if(_type == 3)
     {
-      wantedpos = defaultMQ3;
+      _lecturePosInArray = defaultMQ3;
     }
     else if(_type == 4)
     {
-      wantedpos = defaultMQ4;
+      _lecturePosInArray = defaultMQ4;
     }
     else if(_type == 5)
     {
-      wantedpos = defaultMQ5;
+      _lecturePosInArray = defaultMQ5;
     }
     else if(_type == 6)
     {
-      wantedpos = defaultMQ6;
+      _lecturePosInArray = defaultMQ6;
     }
     else if(_type == 7)
     {
-      wantedpos = defaultMQ7;
+      _lecturePosInArray = defaultMQ7;
     }
     else if(_type == 8)
     {
-      wantedpos = defaultMQ8;
+      _lecturePosInArray = defaultMQ8;
     }
     else if(_type == 9)
     {
-      wantedpos = defaultMQ9;
+      _lecturePosInArray = defaultMQ9;
     }
     else if(_type == 131)
     {
-      wantedpos = defaultMQ131;
+      _lecturePosInArray = defaultMQ131;
     }
     else if(_type == 135)
     {
-      wantedpos = defaultMQ135;
+      _lecturePosInArray = defaultMQ135;
     }
     else if(_type == 303)
     {
-      wantedpos = defaultMQ303;
+      _lecturePosInArray = defaultMQ303;
     }
     else if(_type == 309)
     {
-      wantedpos = defaultMQ309;
+      _lecturePosInArray = defaultMQ309;
     }
   }
   else 
   {
     for (int i=0; i<lecturesAvailable; i++) {
         if (nameLectureRequeired = nameLecture[i]) {    //modified here
-          wantedpos = i;
+          _lecturePosInArray = i;
           break;
         }
       }
   }
     
-  _m = _MQ[indexSlopeLectures[wantedpos]];
-  _b = _MQ[indexBPointLectures[wantedpos]];
+  _m = _MQ[indexSlopeLectures[_lecturePosInArray]];
+  _b = _MQ[indexBPointLectures[_lecturePosInArray]];
 }
+int MQUnifiedsensor::readPPM(int m, int b) {
+  /**
+  * Returns the PPM concentration
+  */
+  double sensor_volt = this->getVoltage();
+  double RS_gas; //Define variable for sensor resistance
+  double ratio; //Define variable for ratio
 
+  RS_gas = ((5.0 * 10.0) / sensor_volt) - 10.0; //Get value of RS in a gas
+
+  ratio = RS_gas / this->_R0;   // Get ratio RS_gas/RS_air
+
+  double ppm_log = (log10(ratio) - b) / m; //Get ppm value in linear scale according to the the ratio value
+  double ppm = pow(10, ppm_log); //Convert ppm value to log scale
+  return floor(ppm);
+}
 double MQUnifiedsensor::calibrate() {
     float sensor_volt; //Define variable for sensor voltage
     float RS_air; //Define variable for sensor resistance
@@ -169,7 +181,6 @@ double MQUnifiedsensor::calibrate() {
     R0 = RS_air / 4.4; //Calculate R0
     return R0;
 }
-
 double MQUnifiedsensor::getVoltage() {
   double avg = 0.0;
   for (int i = 0; i < retries; i ++) {
@@ -181,20 +192,6 @@ double MQUnifiedsensor::getVoltage() {
 
   return voltage;
 }
-  
-  /**
-    * Returns the PPM concentration
-    */
-  int MQUnifiedsensor::readPPM(int m, int b) {
-    double sensor_volt = this->getVoltage();
-    double RS_gas; //Define variable for sensor resistance
-    double ratio; //Define variable for ratio
-
-    RS_gas = ((5.0 * 10.0) / sensor_volt) - 10.0; //Get value of RS in a gas
-
-    ratio = RS_gas / this->_R0;   // Get ratio RS_gas/RS_air
-
-    double ppm_log = (log10(ratio) - b) / m; //Get ppm value in linear scale according to the the ratio value
-    double ppm = pow(10, ppm_log); //Convert ppm value to log scale
-    return floor(ppm);
-  }
\ No newline at end of file
+void MQUnifiedsensor::setR0(double R0) {
+  this->_R0 = R0;
+}
\ No newline at end of file
diff --git a/src/MQUnifiedsensor.h b/src/MQUnifiedsensor.h
index 4c7583a..580e65f 100644
--- a/src/MQUnifiedsensor.h
+++ b/src/MQUnifiedsensor.h
@@ -13,24 +13,17 @@ class MQUnifiedsensor
      * Constructor
      */
     MQUnifiedsensor(int pin, int type);
+    void inicializar();
     void setR0(double R0);
     void setSensorCharacteristics(String nameLectureReqeuired);
     
     int readSensor(String nameLectureRequeired = "", bool print = false);
     int readPPM(int m, int b);
-    void inicializar();
-
-    /**
-     * Calibrates the start point of 400
-    */    
-    double calibrate();
-
-    /**
-     * Returns the voltage
-     */
-    double getVoltage();
     
+    double calibrate();
+    double getVoltage();
 
+    String getnameLecture();
     /**
      * Returns the PPM concentration    
     MQ-2 - Methane, Butane, LPG, smoke
@@ -52,9 +45,9 @@ class MQUnifiedsensor
     
     /* Index definitions and header names*/
 
-    String nameLecture[lecturesAvailable] = {"H2","LPG","CH4","CO","Alcohol","Propane","Benzine","Hexane","Smoke","Nox","CL2","O3","CO2","Tolueno","NH4","Acetona","Iso-butano","Hydrogeno","Ethanol"};
-    int indexSlopeLectures[lecturesAvailable] ={0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36};
-    int indexBPointLectures[lecturesAvailable] ={1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37};
+    const String nameLecture[lecturesAvailable] = {"H2","LPG","CH4","CO","Alcohol","Propane","Benzine","Hexane","Smoke","Nox","CL2","O3","CO2","Tolueno","NH4","Acetona","Iso-butano","Hydrogeno","Ethanol"};
+    const int indexSlopeLectures[lecturesAvailable] ={0, 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, 32, 34, 36};
+    const int indexBPointLectures[lecturesAvailable] ={1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37};
     const int defaultMQ2 = 4; // LPG
     const int defaultMQ3 = 10; // Alcohol
     const int defaultMQ4 = 6; // CH4
@@ -69,22 +62,22 @@ class MQUnifiedsensor
     const int defaultMQ309 = 8; //CO
 
     /* Value of m (Slope) and b (Cut on x axis) points */
-    double MQ2[38] = {-2.2459,2.9845,-2.2879,2.7901,-2.6208,3.6075,-3.1157,4.5134,-2.7028,3.5595,-2.2879,2.7901,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
-    double MQ3[38] = {0,0,-3.1851,4.7048,-17.531,28.785,-4.339,6.4432,-1.435,0.4103,0,0,-2.7009,0.632,-2.7268,3.6299,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
-    double MQ4[38] = {0,0,-2.5818,3.6303,0.9873,2.6386,-5.5945,5.6693,-11.89,9.0375,0,0,0,0,0,0,-11.189,9.0375,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
-    double MQ5[38] = {-4.368,2.9667,-2.5723,1.8943,-2.4438,2.3044,-4.8188,5.2023,-4.419,4.8044,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
-    double MQ6[38] = {-3.6775,5.0286,-1.6567,2.8775,-1,3.301,-12.791,14.523,-5.8057,7.5292,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
-    double MQ7[38] = {-1.329,1.8864,-7.8626,9.1056,-5.4878,8.8387,-1.4065,2.0162,-6.3219,9.924,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
-    double MQ8[38] = {-0.7152,2.9891,-3.419,7.3513,-7.5609,15.243,-7.0753,15.396,-1.7459,4.7575,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
-    double MQ9[38] = {0,0,-2.2535,2.9855,-1.6012,3.1476,-1.749,2.827,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
-    double MQ131[38] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,-2.7245,3.3004,-1.0333,1.7117,-1.2037,1.6455,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
-    double MQ135[38] = {0,0,0,0,0,0,-2.7268,2.301,-2.8608,1.8627,0,0,0,0,0,0,0,0,0,0,0,0,0,0,-3.2819,1.9903,-5.7015,1.1612,-2.2119,2.0473,-5.9682,1.0175,0,0,0,0,0,0};
-    double MQ303A[38] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,-2.3543,1.144,-2.4338,0.7558,-2.5597,0.4436};
-    double MQ309A[38] = {-2.1311,3.0886,0,0,-1.6554,2.985,-4.7623,6.7413,-3.7686,5.6744,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
+    const double MQ2[38] = {-2.2459,2.9845,-2.2879,2.7901,-2.6208,3.6075,-3.1157,4.5134,-2.7028,3.5595,-2.2879,2.7901,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
+    const double MQ3[38] = {0,0,-3.1851,4.7048,-17.531,28.785,-4.339,6.4432,-1.435,0.4103,0,0,-2.7009,0.632,-2.7268,3.6299,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
+    const double MQ4[38] = {0,0,-2.5818,3.6303,0.9873,2.6386,-5.5945,5.6693,-11.89,9.0375,0,0,0,0,0,0,-11.189,9.0375,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
+    const double MQ5[38] = {-4.368,2.9667,-2.5723,1.8943,-2.4438,2.3044,-4.8188,5.2023,-4.419,4.8044,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
+    const double MQ6[38] = {-3.6775,5.0286,-1.6567,2.8775,-1,3.301,-12.791,14.523,-5.8057,7.5292,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
+    const double MQ7[38] = {-1.329,1.8864,-7.8626,9.1056,-5.4878,8.8387,-1.4065,2.0162,-6.3219,9.924,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
+    const double MQ8[38] = {-0.7152,2.9891,-3.419,7.3513,-7.5609,15.243,-7.0753,15.396,-1.7459,4.7575,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
+    const double MQ9[38] = {0,0,-2.2535,2.9855,-1.6012,3.1476,-1.749,2.827,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
+    const double MQ131[38] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,-2.7245,3.3004,-1.0333,1.7117,-1.2037,1.6455,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
+    const double MQ135[38] = {0,0,0,0,0,0,-2.7268,2.301,-2.8608,1.8627,0,0,0,0,0,0,0,0,0,0,0,0,0,0,-3.2819,1.9903,-5.7015,1.1612,-2.2119,2.0473,-5.9682,1.0175,0,0,0,0,0,0};
+    const double MQ303A[38] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,-2.3543,1.144,-2.4338,0.7558,-2.5597,0.4436};
+    const double MQ309A[38] = {-2.1311,3.0886,0,0,-1.6554,2.985,-4.7623,6.7413,-3.7686,5.6744,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
 
 
   private:
-    int _pin, _type, _PPM;
+    int _pin, _type, _PPM, _lecturePosInArray;
     double _R0, _m, _b, _MQ[38];
     const float VOLT_RESOLUTION = 5.0; // if 3.3v use 3.3
     const int ADC_RESOLUTION = 10; // for 10bit analog to digital converter.