Fix #44 by conditionally excluding unused port and bitmask state on non-AVR platforms.

Author: tdicola

DHT.cpp

@@ -11,8 +11,10 @@ written by Adafruit Industries
 DHT::DHT(uint8_t pin, uint8_t type, uint8_t count) {
   _pin = pin;
   _type = type;
-  _bit = digitalPinToBitMask(pin);
-  _port = digitalPinToPort(pin);
+  #ifdef __AVR
+    _bit = digitalPinToBitMask(pin);
+    _port = digitalPinToPort(pin);
+  #endif
   _maxcycles = microsecondsToClockCycles(1000);  // 1 millisecond timeout for
                                                  // reading pulses from DHT sensor.
   // Note that count is now ignored as the DHT reading algorithm adjusts itself
@@ -95,7 +97,7 @@ float DHT::computeHeatIndex(float temperature, float percentHumidity, bool isFah
   if (!isFahrenheit)
     temperature = convertCtoF(temperature);
 
-  hi = 0.5 * (temperature + 61.0 + ((temperature - 68.0) * 1.2) + (percentHumidity * 0.094)); 
+  hi = 0.5 * (temperature + 61.0 + ((temperature - 68.0) * 1.2) + (percentHumidity * 0.094));
 
   if (hi > 79) {
     hi = -42.379 +

DHT.h

@@ -48,7 +48,12 @@ class DHT {
 
  private:
   uint8_t data[5];
-  uint8_t _pin, _type, _bit, _port;
+  uint8_t _pin, _type;
+  #ifdef __AVR
+    // Use direct GPIO access on an 8-bit AVR so keep track of the port and bitmask
+    // for the digital pin connected to the DHT.  Other platforms will use digitalRead.
+    uint8_t _bit, _port;
+  #endif
   uint32_t _lastreadtime, _maxcycles;
   bool _lastresult;
 

library.properties

@@ -1,5 +1,5 @@
 name=DHT sensor library
-version=1.2.2
+version=1.2.3
 author=Adafruit
 maintainer=Adafruit <[email protected]>
 sentence=Arduino library for DHT11, DHT22, etc Temp & Humidity Sensors