Move changes regarding the filtered airspeed consistently across sensors, use actual air temperature instead of board temperature

src/drivers/ets_airspeed/ets_airspeed.cpp

@@ -176,11 +176,14 @@ ETSAirspeed::collect()
 		_max_differential_pressure_pa = diff_pres_pa;
 	}
 
-	// XXX we may want to smooth out the readings to remove noise.
 	differential_pressure_s report;
 	report.timestamp = hrt_absolute_time();
         report.error_count = perf_event_count(_comms_errors);
 	report.differential_pressure_pa = (float)diff_pres_pa;
+
+	// XXX we may want to smooth out the readings to remove noise.
+	report.differential_pressure_filtered_pa = (float)diff_pres_pa;
+	report.temperature = -1000.0f;
 	report.voltage = 0;
 	report.max_differential_pressure_pa = _max_differential_pressure_pa;
 

src/modules/sensors/sensors.cpp

@@ -1031,10 +1031,12 @@ Sensors::diff_pres_poll(struct sensor_combined_s &raw)
 		raw.differential_pressure_timestamp = _diff_pres.timestamp;
 		raw.differential_pressure_filtered_pa = _diff_pres.differential_pressure_filtered_pa;
 
+		float air_temperature_celcius = (_diff_pres.temperature > -300.0f) ? _diff_pres.temperature : (raw.baro_temp_celcius - PCB_TEMP_ESTIMATE_DEG);
+
 		_airspeed.timestamp = _diff_pres.timestamp;
 		_airspeed.indicated_airspeed_m_s = calc_indicated_airspeed(_diff_pres.differential_pressure_filtered_pa);
 		_airspeed.true_airspeed_m_s = calc_true_airspeed(_diff_pres.differential_pressure_filtered_pa + raw.baro_pres_mbar * 1e2f,
-					      raw.baro_pres_mbar * 1e2f, raw.baro_temp_celcius - PCB_TEMP_ESTIMATE_DEG);
+					      raw.baro_pres_mbar * 1e2f, air_temperature_celcius);
 
 		/* announce the airspeed if needed, just publish else */
 		if (_airspeed_pub > 0) {
@@ -1239,6 +1241,8 @@ Sensors::adc_poll(struct sensor_combined_s &raw)
 
 						_diff_pres.timestamp = t;
 						_diff_pres.differential_pressure_pa = diff_pres_pa;
+						_diff_pres.differential_pressure_filtered_pa = diff_pres_pa;
+						_diff_pres.temperature = -1000.0f;
 						_diff_pres.voltage = voltage;
 
 						/* announce the airspeed if needed, just publish else */

src/modules/uORB/topics/differential_pressure.h

@@ -58,7 +58,7 @@ struct differential_pressure_s {
 	float	differential_pressure_filtered_pa;	/**< Low pass filtered differential pressure reading */
 	float	max_differential_pressure_pa;		/**< Maximum differential pressure reading */
 	float		voltage;			/**< Voltage from analog airspeed sensors (voltage divider already compensated) */
-	float		temperature;			/**< Temperature provided by sensor */
+	float		temperature;			/**< Temperature provided by sensor, -1000.0f if unknown */
 
 };