Added support for DHT12 sensor (thanks to Altan Altay)

code/espurna/sensors/DHTSensor.h

@@ -15,6 +15,7 @@
 #define DHT_MIN_INTERVAL            2000
 
 #define DHT_CHIP_DHT11              11
+#define DHT_CHIP_DHT12              12
 #define DHT_CHIP_DHT22              22
 #define DHT_CHIP_DHT21              21
 #define DHT_CHIP_AM2301             21
@@ -145,7 +146,7 @@ class DHTSensor : public BaseSensor {
             pinMode(_gpio, OUTPUT);
             noInterrupts();
         	digitalWrite(_gpio, LOW);
-            if (_type == DHT_CHIP_DHT11) {
+            if ((_type == DHT_CHIP_DHT11) || (_type == DHT_CHIP_DHT12)) {
                 nice_delay(20);
             } else {
                 delayMicroseconds(500);
@@ -201,6 +202,9 @@ class DHTSensor : public BaseSensor {
         	// Get humidity from Data[0] and Data[1]
             if (_type == DHT_CHIP_DHT11) {
                 _humidity = dhtData[0];
+            } else if (_type == DHT_CHIP_DHT12) {
+                _humidity = dhtData[0];
+				_humidity += dhtData[1] * 0.1;
             } else {
         	    _humidity = dhtData[0] * 256 + dhtData[1];
         	    _humidity /= 10;
@@ -209,6 +213,10 @@ class DHTSensor : public BaseSensor {
         	// Get temp from Data[2] and Data[3]
             if (_type == DHT_CHIP_DHT11) {
                 _temperature = dhtData[2];
+			} else if (_type == DHT_CHIP_DHT12) {
+				_temperature = (dhtData[2] & 0x7F);
+				_temperature += dhtData[3] * 0.1;
+				if (dhtData[2] & 0x80) _temperature *= -1;
             } else {
                 _temperature = (dhtData[2] & 0x7F) * 256 + dhtData[3];
                 _temperature /= 10;
@@ -238,7 +246,7 @@ class DHTSensor : public BaseSensor {
         unsigned char _errors = 0;
 
         double _temperature = 0;
-        unsigned int _humidity = 0;
+        double _humidity = 0;
 
 };