AP_Airspeed: expose get_temperature()

libraries/AP_Airspeed/AP_Airspeed.cpp

@@ -49,7 +49,7 @@ extern const AP_HAL::HAL& hal;
 #elif CONFIG_HAL_BOARD == HAL_BOARD_FLYMAPLE
  #define ARSPD_DEFAULT_PIN 16
 #elif CONFIG_HAL_BOARD == HAL_BOARD_LINUX
- #define ARSPD_DEFAULT_PIN 65
+ #define ARSPD_DEFAULT_PIN AP_AIRSPEED_I2C_PIN
 #else
  #define ARSPD_DEFAULT_PIN 0
 #endif
@@ -122,7 +122,7 @@ float AP_Airspeed::get_pressure(void)
         return 0;
     }
     float pressure = 0;
-    if (_pin == 65) {
+    if (_pin == AP_AIRSPEED_I2C_PIN) {
         _healthy = digital.get_differential_pressure(pressure);
     } else {
         _healthy = analog.get_differential_pressure(pressure);
@@ -130,6 +130,18 @@ float AP_Airspeed::get_pressure(void)
     return pressure;
 }
 
+// get a temperature reading if possible
+bool AP_Airspeed::get_temperature(float &temperature)
+{
+    if (!_enable) {
+        return false;
+    }
+    if (_pin == AP_AIRSPEED_I2C_PIN) {
+        return digital.get_temperature(temperature);
+    }
+    return false;
+}
+
 // calibrate the airspeed. This must be called at least once before
 // the get_airspeed() interface can be used
 void AP_Airspeed::calibrate()

libraries/AP_Airspeed/AP_Airspeed.h

@@ -78,6 +78,9 @@ public:
         return _ratio;
     }
 
+    // get temperature if available
+    bool get_temperature(float &temperature);
+
     // set the airspeed ratio (dimensionless)
     void        set_airspeed_ratio(float ratio) {
         _ratio.set(ratio);
@@ -158,5 +161,8 @@ private:
 #endif
 };
 
+// the virtual pin for digital airspeed sensors
+#define AP_AIRSPEED_I2C_PIN 65
+
 #endif // __AP_AIRSPEED_H__