    **/ 
 }
 
+void phone()
+{
+  
+  if(Serial.available())
+    {
+      if(Serial.read()=='1'){
+          Ki+=0.1;
+          Serial.write("Ki value is incremented");
+      }
+      else if(Serial.read()=='0'){  
+          Kd+=1;
+          Serial.write("Kd value is incremented");
+      }
+      else if(Serial.read()=='2'){
+          Kp+=1;
+          Serial.write("Kp value is incremented");
+      }
+      else if(Serial.read()=='3'){
+          Ki-=0.1;
+          Serial.write("Ki value is decremented");
+      }
+      else if(Serial.read()=='4'){  
+          Kd-=1;
+          Serial.write("Kd value is decremented");
+      }
+      else if(Serial.read()=='5'){
+          Kp-=1;
+          Serial.write("Kp value is decremented");
+      }
+  }
+}

    
    previous_error=error;
    
    Serial.print("pidval : ");
      Serial.print(PID_value);
    Serial.println("\t");
/**
    Serial.print("P : ");
    Serial.print(P);
    Serial.print("\t");


void calculate_pid()
{
    error = (sensors.error)*10;
    P = error;
    I = I + error;
    D = error - previous_error;
