optimied to save space

Opimized to save space.

SD_MHZ19B.cpp

@@ -115,19 +115,6 @@ uint16_t SD_MHZ19B::getDetectionRange(void) {   // last byte is a pre-calculated
 }
 
 
-// returns temperature in degrees Celcium. Should be called after getPPM() function; otherwise, will return a previous value.
-int8_t SD_MHZ19B::getTemp(void) {
-  return ((int8_t)_unionFrame.MHZ19B.temperature - 40);   // corrected temperature
-}
-
-
-// undocumented features
-// returns status of the module. Should be called after getPPM() function; otherwise, will return a previous value.
-uint8_t SD_MHZ19B::getStatus(void) {
-  return _unionFrame.MHZ19B.status;
-}
-
-
 /*
 // returns `Warming` status of the module (not documented, does not work). 
 bool SD_MHZ19::isWarming(void) {
@@ -212,10 +199,12 @@ bool SD_MHZ19B::_readData(void) {
   #endif
 
   // re-sort the buffer: swap high and low bytes since they are not in the "machine" order 
-  uint8_t tmp;
-  tmp = _unionFrame.buffer[2];
-  _unionFrame.buffer[2] = _unionFrame.buffer[3];
-  _unionFrame.buffer[3] = tmp;
+  {
+    uint8_t tmp;  // tmp does not exist outside of the {} scope
+    tmp = _unionFrame.buffer[2];
+    _unionFrame.buffer[2] = _unionFrame.buffer[3];
+    _unionFrame.buffer[3] = tmp;
+  }
 
   // Debug - print received buffer
   #ifdef DEBUG  

SD_MHZ19B.h

@@ -113,7 +113,7 @@ Reads data from the module, fills in an internal data structure;
 Returns PPM value, verified and valid (validate by calculating checkSum of the data received).
 Return zero (false) if error during data read or CRC is not valid.
 */
-uint16_t getPPM();
+uint16_t getPPM(void);
 
 
 /*
@@ -122,17 +122,23 @@ Returns temperature value in degrees Celcium, verified and valid (validate by ca
 The value is available after successful getPPM() reading only; otherwise, returns previous value; to be called after getPPM() only.
 Rather inaccurate ±3*C; is used for internal compensation.
 */
-int8_t getTemp(void);
+int8_t getTemp(void) const {
+  return ((int8_t)_unionFrame.MHZ19B.temperature - 40);   // corrected temperature
+}
 
 // just to ensure compatibility
 #define getTemperature() getTemp()
 
+
 /*
 Reads module status - not documented, always return 0
 Returns status, verified and valid (validate by calculating checkSum of the data received).
 The value is available after successful getPPM() reading only; otherwise, will return previous value; to be called after getPPM() only.
 */
-uint8_t getStatus(void);
+// undocumented features
+uint8_t getStatus(void) const {
+  return _unionFrame.MHZ19B.status;
+}
 
 
 // experimental; undocumented; work in ptogress