Example #1
0
static BOOL _PRS(PDeviceDescriptor_t d, TCHAR *String, NMEA_INFO *_INFO){
	(void)d;
	if(UpdateBaroSource(_INFO, 0, d, StaticPressureToQNHAltitude((HexStrToInt(String)*1.0)))){
		TriggerVarioUpdate();
	}
	return TRUE;
}
Example #2
0
fixed
AtmosphericPressure::AltitudeToQNHAltitude(const fixed alt) const
{
  return StaticPressureToQNHAltitude(fixed(pow((k4 - alt) * k5, inv_k1)));
}
Example #3
0
////////////////////////////////////////////////////////////////////////////////////////////////////////
// $PCPROBE,T,Q0,Q1,Q2,Q3,ax,ay,az,temp,rh,batt,delta_press,abs_press,C,
// - "T" after "$PCPROBE" indicates that the string contains data. Data are represented as signed,
//  16-bit hexadecimal integers. The only exception is abs_press which is in signed 24-bits hex
//  format.
// - Q0, Q1, Q2, Q3: 3D orientation of the C-Probe in quaternion format. Heading, pitch, and roll can
//    be calculated as follows:
//      q0 = Q0 * 0.001;
//      q1 = Q1 * 0.001;
//      q2 = Q2 * 0.001;
//      q3 = Q3 * 0.001;
//      sin_pitch = -2 * (q0 * q2 - q3 * q1); // if sin_pitch > 1 or sin_pitch < -1, discard the data
//      pitch = asin(sin_pitch);
//      heading = M_PI + atan2(2*(q1 * q2 + q3 * q0), q3 * q3 - q0 * q0 - q1 * q1 + q2 * q2);
//      roll = atan2( 2 * (q0 * q1 + q3 * q2), q3 * q3 + q0 * q0 - q1 * q1 - q2 * q2);
// - ax, ay, az: x, y, z components of the acceleration in units of 0.001 g.
// - temp: temperature in units of 0.1°C.
// - rh: relative humidity in units of 0.1%.
// - batt: battery level from 0 to 100%.
// - delta_press: differential pressure (dynamic - static) in units of 0.1 Pa.
// - abs_press: absolute pressure in units of 1/400 Pa
// - C: is transmitted only if the C-Probe is being charged. In this case, heat produced by the charging
//    process is likely to affect the readings of the temperature and humidity sensors.
////////////////////////////////////////////////////////////////////////////////////////////////////////
BOOL CDevCProbe::ParseData( tnmeastring& wiss, NMEA_INFO *pINFO ) {

	double q0 = int16toDouble(HexStrToInt(wiss.GetNextString())) * 0.001;
	double q1 = int16toDouble(HexStrToInt(wiss.GetNextString())) * 0.001;
	double q2 = int16toDouble(HexStrToInt(wiss.GetNextString())) * 0.001;
	double q3 = int16toDouble(HexStrToInt(wiss.GetNextString())) * 0.001;

	double sin_pitch = -2 * (q0 * q2 - q3 * q1); // if sin_pitch > 1 or sin_pitch < -1, discard the data

	if(sin_pitch < 1.0 && sin_pitch > -1.0){
		pINFO->MagneticHeadingAvailable=TRUE;
		pINFO->MagneticHeading = (PI + atan2(2*(q1 * q2 + q3 * q0), q3 * q3 - q0 * q0 - q1 * q1 + q2 * q2))*RAD_TO_DEG;

		pINFO->GyroscopeAvailable=TRUE;
		pINFO->Pitch = asin(sin_pitch)*RAD_TO_DEG;
		pINFO->Roll = atan2( 2 * (q0 * q1 + q3 * q2), q3 * q3 + q0 * q0 - q1 * q1 - q2 * q2)*RAD_TO_DEG;
	}else{
		pINFO->MagneticHeadingAvailable=FALSE;
		pINFO->GyroscopeAvailable=FALSE;
	}

	pINFO->AccelerationAvailable=TRUE;
	pINFO->AccelX = int16toDouble(HexStrToInt(wiss.GetNextString())) * 0.001;
	pINFO->AccelY = int16toDouble(HexStrToInt(wiss.GetNextString())) * 0.001;
	pINFO->AccelZ = int16toDouble(HexStrToInt(wiss.GetNextString())) * 0.001;

	pINFO->TemperatureAvailable=TRUE;
	pINFO->OutsideAirTemperature = int16toDouble(HexStrToInt(wiss.GetNextString())) * 0.1;

	pINFO->HumidityAvailable=TRUE;
	pINFO->RelativeHumidity = int16toDouble(HexStrToInt(wiss.GetNextString())) * 0.1;

	pINFO->ExtBatt1_Voltage = int16toDouble(HexStrToInt(wiss.GetNextString()))+1000;

	double delta_press = int16toDouble(HexStrToInt(wiss.GetNextString())) * 1.0/10.0 ;
	double abs_press = int24toDouble(HexStrToInt(wiss.GetNextString())) * (1.0/4.0);

    LockDeviceData();
	m_delta_press = delta_press;
	m_abs_press = abs_press;
	UnlockDeviceData();
    
    // the highest sea level air pressure ever recorded was 1084 mb (32.01 in.) 
    //  at Siberia associated with an extremely cold air mass.
	if(abs_press > 0.0 && abs_press < 115000.0) {
		UpdateBaroSource(pINFO, BARO__CPROBE, NULL, StaticPressureToQNHAltitude(abs_press));
	}
	else {
		if(pINFO->BaroAltitudeAvailable) {
			abs_press = QNHAltitudeToStaticPressure(pINFO->BaroAltitude);
		}
		else {
			abs_press = QNHAltitudeToStaticPressure(pINFO->Altitude);
		}
	}

	if(delta_press>0.0){
		pINFO->AirspeedAvailable = TRUE;
		pINFO->IndicatedAirspeed = sqrt(2 * delta_press / 1.225);
		pINFO->TrueAirspeed = TrueAirSpeed(delta_press,	pINFO->RelativeHumidity, pINFO->OutsideAirTemperature, abs_press>0.0?abs_press:101325.0);
	}

	if(*(wiss.GetNextString()) == L'C'){
		pINFO->ExtBatt1_Voltage *= -1;
	}

	TriggerVarioUpdate();
	return TRUE;
}
Example #4
0
fixed
AtmosphericPressure::PressureAltitudeToQNHAltitude(const fixed alt) const
{
    return StaticPressureToQNHAltitude(PressureAltitudeToStaticPressure(alt));
}