QKnx2ByteFloat Class

The QKnx2ByteFloat class is a datapoint type for a 2-byte float value. More...

Header: #include <QKnx2ByteFloat>
qmake: QT += knx
Inherits: QKnxFixedSizeDatapointType

Public Functions

QKnx2ByteFloat(float value)
virtual bool setValue(float value)
virtual float value() const

Reimplemented Public Functions

virtual bool isValid() const override

Protected Functions

QKnx2ByteFloat(int subType, float value)

Detailed Description

The QKnx2ByteFloat class is a datapoint type for a 2-byte float value.

This is a fixed size datapoint type with the length of 2 bytes. It is a base class for datapoint types for temperature, brightness in LUX, and wind speed, as well as air pressure, humidity, quality, and flow, for example.

The range for the value of this datapoint type is from -671 088.64 to 670 760.96.

The float is encoded as (0.01*M)*2^E where E and M are encoded as follows in the 2 bytes:


This class is a base class for the following datapoint types:

QKnxAirFlowAir flow in m3/h.-670760 - 670760
QKnxAirQualityAir quality in ppm.0 - 670760
QKnxAmountRainAmount of Rain in liters per square meter (l/m2).-671088.64 - 670760.96
QKnxCurrentCurrent in milli-ampers (mA).-670760 - 670760
QKnxHumidityHumidity as a percentage.0 - 670760
QKnxKelvinPerPercentKelvin per percent (K/Percent).-670760 - 670760
QKnxPowerPower in kilowatts (kW).-670760 - 670760
QKnxPowerDensityPower Density in watts per square meter (W/m2).-670760 - 670760
QKnxPressurePressure in Pascal (Pa).0 - 670760
QKnxTemperatureCelciusTemperature in degrees Celcius.-273 - 670760
QKnxTemperatureChangeChange in temperature (K) per hour.-670760 - 670760
QKnxTemperatureFahrenheitTemperature in degrees Fahrenheit.-459.6 - 670760.96
QKnxTemperatureKelvinTemperature in degrees Kelvin.-670760 - 670760
QKnxTimeMilliSecondTime in milli-seconds (ms).-670760 - 670760
QKnxTimeSecondTime in seconds.-670760 - 670760
QKnxValueLuxBrightness in LUX.0 - 670760
QKnxVoltageVoltage in milli-volts (mV).-670760 - 670760
QKnxVolumeFlowVolume flow in liters per hour (l/h).-670760 - 670760
QKnxWindSpeedWind speed in meters per second (m/s).0 - 670760
QKnxWindSpeedKmPerHourWind speed in kilometers per hour (km/h).0 - 670760.96

See also QKnxDatapointType.

Member Function Documentation


Creates a fixed size datapoint type.

QKnx2ByteFloat::QKnx2ByteFloat(float value)

Creates a fixed size datapoint type with the float value.

[protected] QKnx2ByteFloat::QKnx2ByteFloat(int subType, float value)

Creates a fixed size datapoint type with the subtype subType and float value.

[override virtual] bool QKnx2ByteFloat::isValid() const

Reimplemented from QKnxDatapointType::isValid().

[virtual] bool QKnx2ByteFloat::setValue(float value)

Sets the float of the datapoint type to value.

If the value is outside the allowed range, returns false and does not set the value.

See also value().

[virtual] float QKnx2ByteFloat::value() const

Returns the float stored in the datapoint type.

See also setValue().

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