LabVIEW - Barometer Bricklet

This is the description of the LabVIEW API bindings for the Barometer Bricklet. General information and technical specifications for the Barometer Bricklet are summarized in its hardware description.

An installation guide for the LabVIEW API bindings is part of their general description.

API

Generally, every function of the LabVIEW bindings that outputs a value can report a Tinkerforge.TimeoutException. This error gets reported if the device did not respond. If a cable based connection is used, it is unlikely that this exception gets thrown (assuming nobody plugs the device out). However, if a wireless connection is used, timeouts will occur if the distance to the device gets too big.

The namespace for all Brick/Bricklet bindings and the IPConnection is Tinkerforge.*.

Basic Functions

BrickletBarometer(uid, ipcon) → barometer
Input:
  • uid – Type: String
  • ipcon – Type: .NET Refnum (IPConnection)
Output:
  • barometer – Type: .NET Refnum (BrickletBarometer)

Creates an object with the unique device ID uid. This object can then be used after the IP Connection is connected (see examples above).

BrickletBarometer.GetAirPressure() → airPressure
Output:
  • airPressure – Type: Int32, Unit: 1/1000 hPa, Range: [10000 to 1200000]

Returns the air pressure of the air pressure sensor.

If you want to get the air pressure periodically, it is recommended to use the AirPressureCallback callback and set the period with SetAirPressureCallbackPeriod().

BrickletBarometer.GetAltitude() → altitude
Output:
  • altitude – Type: Int32, Unit: 1 cm, Range: [-231 to 231 - 1]

Returns the relative altitude of the air pressure sensor. The value is calculated based on the difference between the current air pressure and the reference air pressure that can be set with SetReferenceAirPressure().

If you want to get the altitude periodically, it is recommended to use the AltitudeCallback callback and set the period with SetAltitudeCallbackPeriod().

BrickletBarometer.SetReferenceAirPressure(airPressure)
Input:
  • airPressure – Type: Int32, Unit: 1/1000 hPa, Range: [0, 10000 to 1200000], Default: 1013250

Sets the reference air pressure for the altitude calculation. Setting the reference to the current air pressure results in a calculated altitude of 0cm. Passing 0 is a shortcut for passing the current air pressure as reference.

Well known reference values are the Q codes QNH and QFE used in aviation.

BrickletBarometer.GetReferenceAirPressure() → airPressure
Output:
  • airPressure – Type: Int32, Unit: 1/1000 hPa, Range: [10000 to 1200000], Default: 1013250

Returns the reference air pressure as set by SetReferenceAirPressure().

Advanced Functions

BrickletBarometer.GetChipTemperature() → temperature
Output:
  • temperature – Type: Int16, Unit: 1/100 °C, Range: [-4000 to 8500]

Returns the temperature of the air pressure sensor.

This temperature is used internally for temperature compensation of the air pressure measurement. It is not as accurate as the temperature measured by the Temperature Bricklet or the Temperature IR Bricklet.

BrickletBarometer.SetAveraging(movingAveragePressure, averagePressure, averageTemperature)
Input:
  • movingAveragePressure – Type: Byte, Range: [0 to 25], Default: 25
  • averagePressure – Type: Byte, Range: [0 to 10], Default: 10
  • averageTemperature – Type: Byte, Range: [0 to 255], Default: 10

Sets the different averaging parameters. It is possible to set the length of a normal averaging for the temperature and pressure, as well as an additional length of a moving average for the pressure. The moving average is calculated from the normal averages. There is no moving average for the temperature.

Setting the all three parameters to 0 will turn the averaging completely off. If the averaging is off, there is lots of noise on the data, but the data is without delay. Thus we recommend to turn the averaging off if the Barometer Bricklet data is to be used for sensor fusion with other sensors.

New in version 2.0.1 (Plugin).

BrickletBarometer.GetAveraging() → movingAveragePressure, averagePressure, averageTemperature
Output:
  • movingAveragePressure – Type: Byte, Range: [0 to 25], Default: 25
  • averagePressure – Type: Byte, Range: [0 to 10], Default: 10
  • averageTemperature – Type: Byte, Range: [0 to 255], Default: 10

Returns the averaging configuration as set by SetAveraging().

New in version 2.0.1 (Plugin).

BrickletBarometer.GetIdentity() → uid, connectedUid, position, hardwareVersion, firmwareVersion, deviceIdentifier
Output:
  • uid – Type: String, Length: up to 8
  • connectedUid – Type: String, Length: up to 8
  • position – Type: Char, Range: ["a" to "h", "i", "z"]
  • hardwareVersion – Type: Byte[3]
    • 0: major – Type: Byte, Range: [0 to 255]
    • 1: minor – Type: Byte, Range: [0 to 255]
    • 2: revision – Type: Byte, Range: [0 to 255]
  • firmwareVersion – Type: Byte[3]
    • 0: major – Type: Byte, Range: [0 to 255]
    • 1: minor – Type: Byte, Range: [0 to 255]
    • 2: revision – Type: Byte, Range: [0 to 255]
  • deviceIdentifier – Type: Int32, Range: [0 to 216 - 1]

Returns the UID, the UID where the Bricklet is connected to, the position, the hardware and firmware version as well as the device identifier.

The position can be 'a', 'b', 'c', 'd', 'e', 'f', 'g' or 'h' (Bricklet Port). The Raspberry Pi HAT (Zero) Brick is always at position 'i' and the Bricklet connected to an Isolator Bricklet is always as position 'z'.

The device identifier numbers can be found here. There is also a constant for the device identifier of this Bricklet.

Callback Configuration Functions

BrickletBarometer.SetAirPressureCallbackPeriod(period)
Input:
  • period – Type: Int64, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0

Sets the period with which the AirPressureCallback callback is triggered periodically. A value of 0 turns the callback off.

The AirPressureCallback callback is only triggered if the air pressure has changed since the last triggering.

BrickletBarometer.GetAirPressureCallbackPeriod() → period
Output:
  • period – Type: Int64, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0

Returns the period as set by SetAirPressureCallbackPeriod().

BrickletBarometer.SetAltitudeCallbackPeriod(period)
Input:
  • period – Type: Int64, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0

Sets the period with which the AltitudeCallback callback is triggered periodically. A value of 0 turns the callback off.

The AltitudeCallback callback is only triggered if the altitude has changed since the last triggering.

BrickletBarometer.GetAltitudeCallbackPeriod() → period
Output:
  • period – Type: Int64, Unit: 1 ms, Range: [0 to 232 - 1], Default: 0

Returns the period as set by SetAltitudeCallbackPeriod().

BrickletBarometer.SetAirPressureCallbackThreshold(option, min, max)
Input:
  • option – Type: Char, Range: See constants, Default: "x"
  • min – Type: Int32, Unit: 1/1000 hPa, Range: [-231 to 231 - 1], Default: 0
  • max – Type: Int32, Unit: 1/1000 hPa, Range: [-231 to 231 - 1], Default: 0

Sets the thresholds for the AirPressureReachedCallback callback.

The following options are possible:

Option Description
'x' Callback is turned off
'o' Callback is triggered when the air pressure is outside the min and max values
'i' Callback is triggered when the air pressure is inside the min and max values
'<' Callback is triggered when the air pressure is smaller than the min value (max is ignored)
'>' Callback is triggered when the air pressure is greater than the min value (max is ignored)

The following constants are available for this function:

For option:

  • BrickletBarometer.THRESHOLD_OPTION_OFF = "x"
  • BrickletBarometer.THRESHOLD_OPTION_OUTSIDE = "o"
  • BrickletBarometer.THRESHOLD_OPTION_INSIDE = "i"
  • BrickletBarometer.THRESHOLD_OPTION_SMALLER = "<"
  • BrickletBarometer.THRESHOLD_OPTION_GREATER = ">"
BrickletBarometer.GetAirPressureCallbackThreshold() → option, min, max
Output:
  • option – Type: Char, Range: See constants, Default: "x"
  • min – Type: Int32, Unit: 1/1000 hPa, Range: [-231 to 231 - 1], Default: 0
  • max – Type: Int32, Unit: 1/1000 hPa, Range: [-231 to 231 - 1], Default: 0

Returns the threshold as set by SetAirPressureCallbackThreshold().

The following constants are available for this function:

For option:

  • BrickletBarometer.THRESHOLD_OPTION_OFF = "x"
  • BrickletBarometer.THRESHOLD_OPTION_OUTSIDE = "o"
  • BrickletBarometer.THRESHOLD_OPTION_INSIDE = "i"
  • BrickletBarometer.THRESHOLD_OPTION_SMALLER = "<"
  • BrickletBarometer.THRESHOLD_OPTION_GREATER = ">"
BrickletBarometer.SetAltitudeCallbackThreshold(option, min, max)
Input:
  • option – Type: Char, Range: See constants, Default: "x"
  • min – Type: Int32, Unit: 1 cm, Range: [-231 to 231 - 1], Default: 0
  • max – Type: Int32, Unit: 1 cm, Range: [-231 to 231 - 1], Default: 0

Sets the thresholds for the AltitudeReachedCallback callback.

The following options are possible:

Option Description
'x' Callback is turned off
'o' Callback is triggered when the altitude is outside the min and max values
'i' Callback is triggered when the altitude is inside the min and max values
'<' Callback is triggered when the altitude is smaller than the min value (max is ignored)
'>' Callback is triggered when the altitude is greater than the min value (max is ignored)

The following constants are available for this function:

For option:

  • BrickletBarometer.THRESHOLD_OPTION_OFF = "x"
  • BrickletBarometer.THRESHOLD_OPTION_OUTSIDE = "o"
  • BrickletBarometer.THRESHOLD_OPTION_INSIDE = "i"
  • BrickletBarometer.THRESHOLD_OPTION_SMALLER = "<"
  • BrickletBarometer.THRESHOLD_OPTION_GREATER = ">"
BrickletBarometer.GetAltitudeCallbackThreshold() → option, min, max
Output:
  • option – Type: Char, Range: See constants, Default: "x"
  • min – Type: Int32, Unit: 1 cm, Range: [-231 to 231 - 1], Default: 0
  • max – Type: Int32, Unit: 1 cm, Range: [-231 to 231 - 1], Default: 0

Returns the threshold as set by SetAltitudeCallbackThreshold().

The following constants are available for this function:

For option:

  • BrickletBarometer.THRESHOLD_OPTION_OFF = "x"
  • BrickletBarometer.THRESHOLD_OPTION_OUTSIDE = "o"
  • BrickletBarometer.THRESHOLD_OPTION_INSIDE = "i"
  • BrickletBarometer.THRESHOLD_OPTION_SMALLER = "<"
  • BrickletBarometer.THRESHOLD_OPTION_GREATER = ">"
BrickletBarometer.SetDebouncePeriod(debounce)
Input:
  • debounce – Type: Int64, Unit: 1 ms, Range: [0 to 232 - 1], Default: 100

Sets the period with which the threshold callbacks

are triggered, if the thresholds

keep being reached.

BrickletBarometer.GetDebouncePeriod() → debounce
Output:
  • debounce – Type: Int64, Unit: 1 ms, Range: [0 to 232 - 1], Default: 100

Returns the debounce period as set by SetDebouncePeriod().

Callbacks

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done by assigning a function to a callback property of the device object. The available callback property and their type of parameters are described below.

Note

Using callbacks for recurring events is always preferred compared to using getters. It will use less USB bandwidth and the latency will be a lot better, since there is no round trip time.

event BrickletBarometer.AirPressureCallback → sender, airPressure
Callback Output:
  • sender – Type: .NET Refnum (BrickletBarometer)
  • airPressure – Type: Int32, Unit: 1/1000 hPa, Range: [10000 to 1200000]

This callback is triggered periodically with the period that is set by SetAirPressureCallbackPeriod(). The parameter is the air pressure of the air pressure sensor.

The AirPressureCallback callback is only triggered if the air pressure has changed since the last triggering.

event BrickletBarometer.AltitudeCallback → sender, altitude
Callback Output:
  • sender – Type: .NET Refnum (BrickletBarometer)
  • altitude – Type: Int32, Unit: 1 cm, Range: [-231 to 231 - 1]

This callback is triggered periodically with the period that is set by SetAltitudeCallbackPeriod(). The parameter is the altitude of the air pressure sensor.

The AltitudeCallback callback is only triggered if the altitude has changed since the last triggering.

event BrickletBarometer.AirPressureReachedCallback → sender, airPressure
Callback Output:
  • sender – Type: .NET Refnum (BrickletBarometer)
  • airPressure – Type: Int32, Unit: 1/1000 hPa, Range: [10000 to 1200000]

This callback is triggered when the threshold as set by SetAirPressureCallbackThreshold() is reached. The parameter is the air pressure of the air pressure sensor.

If the threshold keeps being reached, the callback is triggered periodically with the period as set by SetDebouncePeriod().

event BrickletBarometer.AltitudeReachedCallback → sender, altitude
Callback Output:
  • sender – Type: .NET Refnum (BrickletBarometer)
  • altitude – Type: Int32, Unit: 1 cm, Range: [-231 to 231 - 1]

This callback is triggered when the threshold as set by SetAltitudeCallbackThreshold() is reached. The parameter is the altitude of the air pressure sensor.

If the threshold keeps being reached, the callback is triggered periodically with the period as set by SetDebouncePeriod().

Virtual Functions

Virtual functions don't communicate with the device itself, but operate only on the API bindings device object. They can be called without the corresponding IP Connection object being connected.

BrickletBarometer.GetAPIVersion() → apiVersion
Output:
  • apiVersion – Type: Byte[3]
    • 0: major – Type: Byte, Range: [0 to 255]
    • 1: minor – Type: Byte, Range: [0 to 255]
    • 2: revision – Type: Byte, Range: [0 to 255]

Returns the version of the API definition implemented by this API bindings. This is neither the release version of this API bindings nor does it tell you anything about the represented Brick or Bricklet.

BrickletBarometer.GetResponseExpected(functionId) → responseExpected
Input:
  • functionId – Type: Byte, Range: See constants
Output:
  • responseExpected – Type: Boolean

Returns the response expected flag for the function specified by the function ID parameter. It is true if the function is expected to send a response, false otherwise.

For getter functions this is enabled by default and cannot be disabled, because those functions will always send a response. For callback configuration functions it is enabled by default too, but can be disabled by SetResponseExpected(). For setter functions it is disabled by default and can be enabled.

Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is send and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

For functionId:

  • BrickletBarometer.FUNCTION_SET_AIR_PRESSURE_CALLBACK_PERIOD = 3
  • BrickletBarometer.FUNCTION_SET_ALTITUDE_CALLBACK_PERIOD = 5
  • BrickletBarometer.FUNCTION_SET_AIR_PRESSURE_CALLBACK_THRESHOLD = 7
  • BrickletBarometer.FUNCTION_SET_ALTITUDE_CALLBACK_THRESHOLD = 9
  • BrickletBarometer.FUNCTION_SET_DEBOUNCE_PERIOD = 11
  • BrickletBarometer.FUNCTION_SET_REFERENCE_AIR_PRESSURE = 13
  • BrickletBarometer.FUNCTION_SET_AVERAGING = 20
BrickletBarometer.SetResponseExpected(functionId, responseExpected)
Input:
  • functionId – Type: Byte, Range: See constants
  • responseExpected – Type: Boolean

Changes the response expected flag of the function specified by the function ID parameter. This flag can only be changed for setter (default value: false) and callback configuration functions (default value: true). For getter functions it is always enabled.

Enabling the response expected flag for a setter function allows to detect timeouts and other error conditions calls of this setter as well. The device will then send a response for this purpose. If this flag is disabled for a setter function then no response is send and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

For functionId:

  • BrickletBarometer.FUNCTION_SET_AIR_PRESSURE_CALLBACK_PERIOD = 3
  • BrickletBarometer.FUNCTION_SET_ALTITUDE_CALLBACK_PERIOD = 5
  • BrickletBarometer.FUNCTION_SET_AIR_PRESSURE_CALLBACK_THRESHOLD = 7
  • BrickletBarometer.FUNCTION_SET_ALTITUDE_CALLBACK_THRESHOLD = 9
  • BrickletBarometer.FUNCTION_SET_DEBOUNCE_PERIOD = 11
  • BrickletBarometer.FUNCTION_SET_REFERENCE_AIR_PRESSURE = 13
  • BrickletBarometer.FUNCTION_SET_AVERAGING = 20
BrickletBarometer.SetResponseExpectedAll(responseExpected)
Input:
  • responseExpected – Type: Boolean

Changes the response expected flag for all setter and callback configuration functions of this device at once.

Constants

BrickletBarometer.DEVICE_IDENTIFIER

This constant is used to identify a Barometer Bricklet.

The GetIdentity() function and the IPConnection.EnumerateCallback callback of the IP Connection have a deviceIdentifier parameter to specify the Brick's or Bricklet's type.

BrickletBarometer.DEVICE_DISPLAY_NAME

This constant represents the human readable name of a Barometer Bricklet.