Software / API Bindings / Go / API Reference and Examples / Bricklets / Barometer Bricklet 2.0

Go - Barometer Bricklet 2.0¶

This is the description of the Go API bindings for the Barometer Bricklet 2.0. General information and technical specifications for the Barometer Bricklet 2.0 are summarized in its hardware description.

An installation guide for the Go API bindings is part of their general description. Additional documentation can be found on godoc.org.

Examples¶

The example code below is Public Domain (CC0 1.0).

Callback¶

Download (example_callback.go)

package main

import (
    "fmt"
    "github.com/Tinkerforge/go-api-bindings/barometer_v2_bricklet"
    "github.com/Tinkerforge/go-api-bindings/ipconnection"
)

const ADDR string = "localhost:4223"
const UID string = "XYZ" // Change XYZ to the UID of your Barometer Bricklet 2.0.

func main() {
    ipcon := ipconnection.New()
    defer ipcon.Close()
    b, _ := barometer_v2_bricklet.New(UID, &ipcon) // Create device object.

    ipcon.Connect(ADDR) // Connect to brickd.
    defer ipcon.Disconnect()
    // Don't use device before ipcon is connected.

    b.RegisterAirPressureCallback(func(airPressure int32) {
        fmt.Printf("Air Pressure: %f hPa\n", float64(airPressure)/1000.0)
    })

    // Set period for air pressure callback to 1s (1000ms) without a threshold.
    b.SetAirPressureCallbackConfiguration(1000, false, 'x', 0, 0)

    fmt.Print("Press enter to exit.")
    fmt.Scanln()
}

Simple¶

Download (example_simple.go)

package main

import (
    "fmt"
    "github.com/Tinkerforge/go-api-bindings/barometer_v2_bricklet"
    "github.com/Tinkerforge/go-api-bindings/ipconnection"
)

const ADDR string = "localhost:4223"
const UID string = "XYZ" // Change XYZ to the UID of your Barometer Bricklet 2.0.

func main() {
    ipcon := ipconnection.New()
    defer ipcon.Close()
    b, _ := barometer_v2_bricklet.New(UID, &ipcon) // Create device object.

    ipcon.Connect(ADDR) // Connect to brickd.
    defer ipcon.Disconnect()
    // Don't use device before ipcon is connected.

    // Get current air pressure.
    airPressure, _ := b.GetAirPressure()
    fmt.Printf("Air Pressure: %f hPa\n", float64(airPressure)/1000.0)

    // Get current altitude.
    altitude, _ := b.GetAltitude()
    fmt.Printf("Altitude: %f m\n", float64(altitude)/1000.0)

    fmt.Print("Press enter to exit.")
    fmt.Scanln()
}

Threshold¶

Download (example_threshold.go)

package main

import (
    "fmt"
    "github.com/Tinkerforge/go-api-bindings/barometer_v2_bricklet"
    "github.com/Tinkerforge/go-api-bindings/ipconnection"
)

const ADDR string = "localhost:4223"
const UID string = "XYZ" // Change XYZ to the UID of your Barometer Bricklet 2.0.

func main() {
    ipcon := ipconnection.New()
    defer ipcon.Close()
    b, _ := barometer_v2_bricklet.New(UID, &ipcon) // Create device object.

    ipcon.Connect(ADDR) // Connect to brickd.
    defer ipcon.Disconnect()
    // Don't use device before ipcon is connected.

    b.RegisterAirPressureCallback(func(airPressure int32) {
        fmt.Printf("Air Pressure: %f hPa\n", float64(airPressure)/1000.0)
        fmt.Println("Enjoy the potentially good weather!")
    })

    // Configure threshold for air pressure "greater than 1025 hPa"
    // with a debounce period of 1s (1000ms).
    b.SetAirPressureCallbackConfiguration(1000, false, '>', 1025*1000, 0)

    fmt.Print("Press enter to exit.")
    fmt.Scanln()
}

API¶

The Barometer Bricklet 2.0 API is defined in the package github.com/Tinkerforge/go-api-bindings/barometer_v2_bricklet

Nearly every function of the Go bindings can return an ipconnection.DeviceError, implementing the error interface. The error can have one of the following values:

ipconnection.DeviceErrorSuccess = 0
ipconnection.DeviceErrorInvalidParameter = 1
ipconnection.DeviceErrorFunctionNotSupported = 2
ipconnection.DeviceErrorUnknownError = 3

which correspond to the values returned from Bricks and Bricklets.

All functions listed below are thread-safe.

Basic Functions¶

func barometer_v2_bricklet.New(uid string, ipcon *IPConnection) (device BarometerV2Bricklet, err error)¶

Parameters:	uid – Type: string ipcon – Type: *IPConnection
Returns:	device – Type: BarometerV2Bricklet err – Type: error

Creates a new BarometerV2Bricklet object with the unique device ID uid and adds it to the IPConnection ipcon:

device, err := barometer_v2_bricklet.New("YOUR_DEVICE_UID", &ipcon)

This device object can be used after the IPConnection has been connected.

func (*BarometerV2Bricklet) GetAirPressure() (airPressure int32, err error)¶

Returns:	airPressure – Type: int32, Unit: 1/1000 hPa, Range: [260000 to 1260000] err – Type: error

Returns the measured air pressure.

If you want to get the value periodically, it is recommended to use the AirPressureCallback callback. You can set the callback configuration with SetAirPressureCallbackConfiguration().

func (*BarometerV2Bricklet) GetAltitude() (altitude int32, err error)¶

Returns:	altitude – Type: int32, Unit: 1 mm, Range: [-2³¹ to 2³¹ - 1] err – Type: error

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 value periodically, it is recommended to use the AltitudeCallback callback. You can set the callback configuration with SetAltitudeCallbackConfiguration().

func (*BarometerV2Bricklet) GetTemperature() (temperature int32, err error)¶

Returns:	temperature – Type: int32, Unit: 1/100 °C, Range: [-4000 to 8500] err – Type: error

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 2.0 or the Temperature IR Bricklet 2.0.

If you want to get the value periodically, it is recommended to use the TemperatureCallback callback. You can set the callback configuration with SetTemperatureCallbackConfiguration().

func (*BarometerV2Bricklet) SetMovingAverageConfiguration(movingAverageLengthAirPressure uint16, movingAverageLengthTemperature uint16) (err error)¶

Parameters:	movingAverageLengthAirPressure – Type: uint16, Range: [1 to 1000], Default: 100 movingAverageLengthTemperature – Type: uint16, Range: [1 to 1000], Default: 100
Returns:	err – Type: error

Sets the length of a moving averaging for the air pressure and temperature measurements.

Setting the length to 1 will turn the averaging off. With less averaging, there is more noise on the data.

If you want to do long term measurements the longest moving average will give the cleanest results.

func (*BarometerV2Bricklet) GetMovingAverageConfiguration() (movingAverageLengthAirPressure uint16, movingAverageLengthTemperature uint16, err error)¶

Returns:	movingAverageLengthAirPressure – Type: uint16, Range: [1 to 1000], Default: 100 movingAverageLengthTemperature – Type: uint16, Range: [1 to 1000], Default: 100 err – Type: error

Returns the moving average configuration as set by SetMovingAverageConfiguration().

func (*BarometerV2Bricklet) SetReferenceAirPressure(airPressure int32) (err error)¶

Parameters:	airPressure – Type: int32, Unit: 1/1000 hPa, Range: [0, 260000 to 1260000], Default: 1013250
Returns:	err – Type: error

Sets the reference air pressure for the altitude calculation. Setting the reference to the current air pressure results in a calculated altitude of 0mm. 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.

func (*BarometerV2Bricklet) GetReferenceAirPressure() (airPressure int32, err error)¶

Returns:	airPressure – Type: int32, Unit: 1/1000 hPa, Range: [260000 to 1260000], Default: 1013250 err – Type: error

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

Advanced Functions¶

func (*BarometerV2Bricklet) SetCalibration(measuredAirPressure int32, actualAirPressure int32) (err error)¶

Parameters:	measuredAirPressure – Type: int32, Unit: 1/1000 hPa, Range: [0, 260000 to 1260000] actualAirPressure – Type: int32, Unit: 1/1000 hPa, Range: [0, 260000 to 1260000]
Returns:	err – Type: error

Sets the one point calibration (OPC) values for the air pressure measurement.

Before the Bricklet can be calibrated any previous calibration has to be removed by setting measured air pressure and actual air pressure to 0.

Then the current air pressure has to be measured using the Bricklet (measured air pressure) and with an accurate reference barometer (actual air pressure) at the same time and passed to this function.

After proper calibration the air pressure measurement can achieve an accuracy up to 0.2 hPa.

The calibration is saved in the EEPROM of the Bricklet and only needs to be configured once.

func (*BarometerV2Bricklet) GetCalibration() (measuredAirPressure int32, actualAirPressure int32, err error)¶

Returns:	measuredAirPressure – Type: int32, Unit: 1/1000 hPa, Range: [0, 260000 to 1260000] actualAirPressure – Type: int32, Unit: 1/1000 hPa, Range: [0, 260000 to 1260000] err – Type: error

Returns the air pressure one point calibration values as set by SetCalibration().

func (*BarometerV2Bricklet) SetSensorConfiguration(dataRate uint8, airPressureLowPassFilter uint8) (err error)¶

Parameters:	dataRate – Type: uint8, Range: See constants, Default: 4 airPressureLowPassFilter – Type: uint8, Range: See constants, Default: 1
Returns:	err – Type: error

Configures the data rate and air pressure low pass filter. The low pass filter cut-off frequency (if enabled) can be set to 1/9th or 1/20th of the configure data rate to decrease the noise on the air pressure data.

The low pass filter configuration only applies to the air pressure measurement. There is no low pass filter for the temperature measurement.

A higher data rate will result in a less precise temperature because of self-heating of the sensor. If the accuracy of the temperature reading is important to you, we would recommend the 1Hz data rate.

The following constants are available for this function:

For dataRate:

barometer_v2_bricklet.DataRateOff = 0
barometer_v2_bricklet.DataRate1Hz = 1
barometer_v2_bricklet.DataRate10Hz = 2
barometer_v2_bricklet.DataRate25Hz = 3
barometer_v2_bricklet.DataRate50Hz = 4
barometer_v2_bricklet.DataRate75Hz = 5

For airPressureLowPassFilter:

barometer_v2_bricklet.LowPassFilterOff = 0
barometer_v2_bricklet.LowPassFilter1_9th = 1
barometer_v2_bricklet.LowPassFilter1_20th = 2

func (*BarometerV2Bricklet) GetSensorConfiguration() (dataRate uint8, airPressureLowPassFilter uint8, err error)¶

Returns:	dataRate – Type: uint8, Range: See constants, Default: 4 airPressureLowPassFilter – Type: uint8, Range: See constants, Default: 1 err – Type: error

Returns the sensor configuration as set by SetSensorConfiguration().

The following constants are available for this function:

For dataRate:

barometer_v2_bricklet.DataRateOff = 0
barometer_v2_bricklet.DataRate1Hz = 1
barometer_v2_bricklet.DataRate10Hz = 2
barometer_v2_bricklet.DataRate25Hz = 3
barometer_v2_bricklet.DataRate50Hz = 4
barometer_v2_bricklet.DataRate75Hz = 5

For airPressureLowPassFilter:

barometer_v2_bricklet.LowPassFilterOff = 0
barometer_v2_bricklet.LowPassFilter1_9th = 1
barometer_v2_bricklet.LowPassFilter1_20th = 2

func (*BarometerV2Bricklet) GetSPITFPErrorCount() (errorCountAckChecksum uint32, errorCountMessageChecksum uint32, errorCountFrame uint32, errorCountOverflow uint32, err error)¶

Returns:	errorCountAckChecksum – Type: uint32, Range: [0 to 2³² - 1] errorCountMessageChecksum – Type: uint32, Range: [0 to 2³² - 1] errorCountFrame – Type: uint32, Range: [0 to 2³² - 1] errorCountOverflow – Type: uint32, Range: [0 to 2³² - 1] err – Type: error

Returns the error count for the communication between Brick and Bricklet.

The errors are divided into

ACK checksum errors,
message checksum errors,
framing errors and
overflow errors.

The errors counts are for errors that occur on the Bricklet side. All Bricks have a similar function that returns the errors on the Brick side.

func (*BarometerV2Bricklet) SetStatusLEDConfig(config uint8) (err error)¶

Parameters:	config – Type: uint8, Range: See constants, Default: 3
Returns:	err – Type: error

Sets the status LED configuration. By default the LED shows communication traffic between Brick and Bricklet, it flickers once for every 10 received data packets.

You can also turn the LED permanently on/off or show a heartbeat.

If the Bricklet is in bootloader mode, the LED is will show heartbeat by default.

The following constants are available for this function:

For config:

barometer_v2_bricklet.StatusLEDConfigOff = 0
barometer_v2_bricklet.StatusLEDConfigOn = 1
barometer_v2_bricklet.StatusLEDConfigShowHeartbeat = 2
barometer_v2_bricklet.StatusLEDConfigShowStatus = 3

func (*BarometerV2Bricklet) GetStatusLEDConfig() (config uint8, err error)¶

Returns:	config – Type: uint8, Range: See constants, Default: 3 err – Type: error

Returns the configuration as set by SetStatusLEDConfig()

The following constants are available for this function:

For config:

barometer_v2_bricklet.StatusLEDConfigOff = 0
barometer_v2_bricklet.StatusLEDConfigOn = 1
barometer_v2_bricklet.StatusLEDConfigShowHeartbeat = 2
barometer_v2_bricklet.StatusLEDConfigShowStatus = 3

func (*BarometerV2Bricklet) GetChipTemperature() (temperature int16, err error)¶

Returns:	temperature – Type: int16, Unit: 1 °C, Range: [-2¹⁵ to 2¹⁵ - 1] err – Type: error

Returns the temperature as measured inside the microcontroller. The value returned is not the ambient temperature!

The temperature is only proportional to the real temperature and it has bad accuracy. Practically it is only useful as an indicator for temperature changes.

func (*BarometerV2Bricklet) Reset() (err error)¶

Returns:	err – Type: error

Calling this function will reset the Bricklet. All configurations will be lost.

After a reset you have to create new device objects, calling functions on the existing ones will result in undefined behavior!

func (*BarometerV2Bricklet) GetIdentity() (uid string, connectedUid string, position rune, hardwareVersion [3]uint8, firmwareVersion [3]uint8, deviceIdentifier uint16, err error)¶

Returns:

Returns:	uid – Type: string, Length: up to 8 connectedUid – Type: string, Length: up to 8 position – Type: rune, Range: ['a' to 'h', 'z'] hardwareVersion – Type: [3]uint8 0: major – Type: uint8, Range: [0 to 255] 1: minor – Type: uint8, Range: [0 to 255] 2: revision – Type: uint8, Range: [0 to 255] firmwareVersion – Type: [3]uint8 0: major – Type: uint8, Range: [0 to 255] 1: minor – Type: uint8, Range: [0 to 255] 2: revision – Type: uint8, Range: [0 to 255] deviceIdentifier – Type: uint16, Range: [0 to 2¹⁶ - 1] err – Type: error

uid – Type: string, Length: up to 8
connectedUid – Type: string, Length: up to 8
position – Type: rune, Range: ['a' to 'h', 'z']
hardwareVersion – Type: [3]uint8

0: major – Type: uint8, Range: [0 to 255]
1: minor – Type: uint8, Range: [0 to 255]
2: revision – Type: uint8, Range: [0 to 255]

firmwareVersion – Type: [3]uint8

0: major – Type: uint8, Range: [0 to 255]
1: minor – Type: uint8, Range: [0 to 255]
2: revision – Type: uint8, Range: [0 to 255]

deviceIdentifier – Type: uint16, Range: [0 to 2¹⁶ - 1]
err – Type: error

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). A Bricklet connected to an Isolator Bricklet is always at 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¶

func (*BarometerV2Bricklet) SetAirPressureCallbackConfiguration(period uint32, valueHasToChange bool, option rune, min int32, max int32) (err error)¶

Parameters:	period – Type: uint32, Unit: 1 ms, Range: [0 to 2³² - 1], Default: 0 valueHasToChange – Type: bool, Default: false option – Type: rune, 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:	err – Type: error

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

If the value has to change-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.

If it is set to false, the callback is continuously triggered with the period, independent of the value.

It is furthermore possible to constrain the callback with thresholds.

The option-parameter together with min/max sets a threshold for the AirPressureCallback callback.

The following options are possible:

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

If the option is set to 'x' (threshold turned off) the callback is triggered with the fixed period.

The following constants are available for this function:

For option:

barometer_v2_bricklet.ThresholdOptionOff = 'x'
barometer_v2_bricklet.ThresholdOptionOutside = 'o'
barometer_v2_bricklet.ThresholdOptionInside = 'i'
barometer_v2_bricklet.ThresholdOptionSmaller = '<'
barometer_v2_bricklet.ThresholdOptionGreater = '>'

func (*BarometerV2Bricklet) GetAirPressureCallbackConfiguration() (period uint32, valueHasToChange bool, option rune, min int32, max int32, err error)¶

Returns:	period – Type: uint32, Unit: 1 ms, Range: [0 to 2³² - 1], Default: 0 valueHasToChange – Type: bool, Default: false option – Type: rune, 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 err – Type: error

Returns the callback configuration as set by SetAirPressureCallbackConfiguration().

The following constants are available for this function:

For option:

barometer_v2_bricklet.ThresholdOptionOff = 'x'
barometer_v2_bricklet.ThresholdOptionOutside = 'o'
barometer_v2_bricklet.ThresholdOptionInside = 'i'
barometer_v2_bricklet.ThresholdOptionSmaller = '<'
barometer_v2_bricklet.ThresholdOptionGreater = '>'

func (*BarometerV2Bricklet) SetAltitudeCallbackConfiguration(period uint32, valueHasToChange bool, option rune, min int32, max int32) (err error)¶

Parameters:	period – Type: uint32, Unit: 1 ms, Range: [0 to 2³² - 1], Default: 0 valueHasToChange – Type: bool, Default: false option – Type: rune, Range: See constants, Default: 'x' min – Type: int32, Unit: 1 mm, Range: [-2³¹ to 2³¹ - 1], Default: 0 max – Type: int32, Unit: 1 mm, Range: [-2³¹ to 2³¹ - 1], Default: 0
Returns:	err – Type: error

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

If it is set to false, the callback is continuously triggered with the period, independent of the value.

It is furthermore possible to constrain the callback with thresholds.

The option-parameter together with min/max sets a threshold for the AltitudeCallback callback.

The following options are possible:

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

If the option is set to 'x' (threshold turned off) the callback is triggered with the fixed period.

The following constants are available for this function:

For option:

barometer_v2_bricklet.ThresholdOptionOff = 'x'
barometer_v2_bricklet.ThresholdOptionOutside = 'o'
barometer_v2_bricklet.ThresholdOptionInside = 'i'
barometer_v2_bricklet.ThresholdOptionSmaller = '<'
barometer_v2_bricklet.ThresholdOptionGreater = '>'

func (*BarometerV2Bricklet) GetAltitudeCallbackConfiguration() (period uint32, valueHasToChange bool, option rune, min int32, max int32, err error)¶

Returns:	period – Type: uint32, Unit: 1 ms, Range: [0 to 2³² - 1], Default: 0 valueHasToChange – Type: bool, Default: false option – Type: rune, Range: See constants, Default: 'x' min – Type: int32, Unit: 1 mm, Range: [-2³¹ to 2³¹ - 1], Default: 0 max – Type: int32, Unit: 1 mm, Range: [-2³¹ to 2³¹ - 1], Default: 0 err – Type: error

Returns the callback configuration as set by SetAltitudeCallbackConfiguration().

The following constants are available for this function:

For option:

barometer_v2_bricklet.ThresholdOptionOff = 'x'
barometer_v2_bricklet.ThresholdOptionOutside = 'o'
barometer_v2_bricklet.ThresholdOptionInside = 'i'
barometer_v2_bricklet.ThresholdOptionSmaller = '<'
barometer_v2_bricklet.ThresholdOptionGreater = '>'

func (*BarometerV2Bricklet) SetTemperatureCallbackConfiguration(period uint32, valueHasToChange bool, option rune, min int32, max int32) (err error)¶

Parameters:	period – Type: uint32, Unit: 1 ms, Range: [0 to 2³² - 1], Default: 0 valueHasToChange – Type: bool, Default: false option – Type: rune, Range: See constants, Default: 'x' min – Type: int32, Unit: 1/100 °C, Range: [-2³¹ to 2³¹ - 1], Default: 0 max – Type: int32, Unit: 1/100 °C, Range: [-2³¹ to 2³¹ - 1], Default: 0
Returns:	err – Type: error

The period is the period with which the TemperatureCallback callback is triggered periodically. A value of 0 turns the callback off.

If it is set to false, the callback is continuously triggered with the period, independent of the value.

It is furthermore possible to constrain the callback with thresholds.

The option-parameter together with min/max sets a threshold for the TemperatureCallback callback.

The following options are possible:

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

If the option is set to 'x' (threshold turned off) the callback is triggered with the fixed period.

The following constants are available for this function:

For option:

barometer_v2_bricklet.ThresholdOptionOff = 'x'
barometer_v2_bricklet.ThresholdOptionOutside = 'o'
barometer_v2_bricklet.ThresholdOptionInside = 'i'
barometer_v2_bricklet.ThresholdOptionSmaller = '<'
barometer_v2_bricklet.ThresholdOptionGreater = '>'

func (*BarometerV2Bricklet) GetTemperatureCallbackConfiguration() (period uint32, valueHasToChange bool, option rune, min int32, max int32, err error)¶

Returns:	period – Type: uint32, Unit: 1 ms, Range: [0 to 2³² - 1], Default: 0 valueHasToChange – Type: bool, Default: false option – Type: rune, Range: See constants, Default: 'x' min – Type: int32, Unit: 1/100 °C, Range: [-2³¹ to 2³¹ - 1], Default: 0 max – Type: int32, Unit: 1/100 °C, Range: [-2³¹ to 2³¹ - 1], Default: 0 err – Type: error

Returns the callback configuration as set by SetTemperatureCallbackConfiguration().

The following constants are available for this function:

For option:

barometer_v2_bricklet.ThresholdOptionOff = 'x'
barometer_v2_bricklet.ThresholdOptionOutside = 'o'
barometer_v2_bricklet.ThresholdOptionInside = 'i'
barometer_v2_bricklet.ThresholdOptionSmaller = '<'
barometer_v2_bricklet.ThresholdOptionGreater = '>'

Callbacks¶

Callbacks can be registered to receive time critical or recurring data from the device. The registration is done with the corresponding Register*Callback function, which returns a unique callback ID. This ID can be used to deregister the callback later with the corresponding Deregister*Callback function.

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.

func (*BarometerV2Bricklet) RegisterAirPressureCallback(func(airPressure int32)) (registrationId uint64)¶

Callback Parameters:	airPressure – Type: int32, Unit: 1/1000 hPa, Range: [260000 to 1260000]
Returns:	registrationId – Type: uint64

This callback is triggered periodically according to the configuration set by SetAirPressureCallbackConfiguration().

The callback parameter is the same as GetAirPressure().

func (*BarometerV2Bricklet) RegisterAltitudeCallback(func(altitude int32)) (registrationId uint64)¶

Callback Parameters:	altitude – Type: int32, Unit: 1 mm, Range: [-2³¹ to 2³¹ - 1]
Returns:	registrationId – Type: uint64

This callback is triggered periodically according to the configuration set by SetAltitudeCallbackConfiguration().

The callback parameter is the same as GetAltitude().

func (*BarometerV2Bricklet) RegisterTemperatureCallback(func(temperature int32)) (registrationId uint64)¶

Callback Parameters:	temperature – Type: int32, Unit: 1/100 °C, Range: [-4000 to 8500]
Returns:	registrationId – Type: uint64

This callback is triggered periodically according to the configuration set by SetTemperatureCallbackConfiguration().

The callback parameter is the same as GetTemperature().

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.

func (*BarometerV2Bricklet) GetAPIVersion() (apiVersion [3]uint8, err error)¶

Returns:	apiVersion – Type: [3]uint8 0: major – Type: uint8, Range: [0 to 255] 1: minor – Type: uint8, Range: [0 to 255] 2: revision – Type: uint8, Range: [0 to 255] err – Type: error

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.

func (*BarometerV2Bricklet) GetResponseExpected(functionId uint8) (responseExpected bool, err error)¶

Parameters:	functionId – Type: uint8, Range: See constants
Returns:	responseExpected – Type: bool err – Type: error

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 sent and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

For functionId:

barometer_v2_bricklet.FunctionSetAirPressureCallbackConfiguration = 2
barometer_v2_bricklet.FunctionSetAltitudeCallbackConfiguration = 6
barometer_v2_bricklet.FunctionSetTemperatureCallbackConfiguration = 10
barometer_v2_bricklet.FunctionSetMovingAverageConfiguration = 13
barometer_v2_bricklet.FunctionSetReferenceAirPressure = 15
barometer_v2_bricklet.FunctionSetCalibration = 17
barometer_v2_bricklet.FunctionSetSensorConfiguration = 19
barometer_v2_bricklet.FunctionSetWriteFirmwarePointer = 237
barometer_v2_bricklet.FunctionSetStatusLEDConfig = 239
barometer_v2_bricklet.FunctionReset = 243
barometer_v2_bricklet.FunctionWriteUID = 248

func (*BarometerV2Bricklet) SetResponseExpected(functionId uint8, responseExpected bool) (err error)¶

Parameters:	functionId – Type: uint8, Range: See constants responseExpected – Type: bool
Returns:	err – Type: error

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.

The following constants are available for this function:

For functionId:

barometer_v2_bricklet.FunctionSetAirPressureCallbackConfiguration = 2
barometer_v2_bricklet.FunctionSetAltitudeCallbackConfiguration = 6
barometer_v2_bricklet.FunctionSetTemperatureCallbackConfiguration = 10
barometer_v2_bricklet.FunctionSetMovingAverageConfiguration = 13
barometer_v2_bricklet.FunctionSetReferenceAirPressure = 15
barometer_v2_bricklet.FunctionSetCalibration = 17
barometer_v2_bricklet.FunctionSetSensorConfiguration = 19
barometer_v2_bricklet.FunctionSetWriteFirmwarePointer = 237
barometer_v2_bricklet.FunctionSetStatusLEDConfig = 239
barometer_v2_bricklet.FunctionReset = 243
barometer_v2_bricklet.FunctionWriteUID = 248

func (*BarometerV2Bricklet) SetResponseExpectedAll(responseExpected bool) (err error)¶

Parameters:	responseExpected – Type: bool
Returns:	err – Type: error

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

Internal Functions¶

Internal functions are used for maintenance tasks such as flashing a new firmware of changing the UID of a Bricklet. These task should be performed using Brick Viewer instead of using the internal functions directly.

func (*BarometerV2Bricklet) SetBootloaderMode(mode uint8) (status uint8, err error)¶

Parameters:	mode – Type: uint8, Range: See constants
Returns:	status – Type: uint8, Range: See constants err – Type: error

Sets the bootloader mode and returns the status after the requested mode change was instigated.

You can change from bootloader mode to firmware mode and vice versa. A change from bootloader mode to firmware mode will only take place if the entry function, device identifier and CRC are present and correct.

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

The following constants are available for this function:

For mode:

barometer_v2_bricklet.BootloaderModeBootloader = 0
barometer_v2_bricklet.BootloaderModeFirmware = 1
barometer_v2_bricklet.BootloaderModeBootloaderWaitForReboot = 2
barometer_v2_bricklet.BootloaderModeFirmwareWaitForReboot = 3
barometer_v2_bricklet.BootloaderModeFirmwareWaitForEraseAndReboot = 4

For status:

barometer_v2_bricklet.BootloaderStatusOK = 0
barometer_v2_bricklet.BootloaderStatusInvalidMode = 1
barometer_v2_bricklet.BootloaderStatusNoChange = 2
barometer_v2_bricklet.BootloaderStatusEntryFunctionNotPresent = 3
barometer_v2_bricklet.BootloaderStatusDeviceIdentifierIncorrect = 4
barometer_v2_bricklet.BootloaderStatusCRCMismatch = 5

func (*BarometerV2Bricklet) GetBootloaderMode() (mode uint8, err error)¶

Returns:	mode – Type: uint8, Range: See constants err – Type: error

Returns the current bootloader mode, see SetBootloaderMode().

The following constants are available for this function:

For mode:

barometer_v2_bricklet.BootloaderModeBootloader = 0
barometer_v2_bricklet.BootloaderModeFirmware = 1
barometer_v2_bricklet.BootloaderModeBootloaderWaitForReboot = 2
barometer_v2_bricklet.BootloaderModeFirmwareWaitForReboot = 3
barometer_v2_bricklet.BootloaderModeFirmwareWaitForEraseAndReboot = 4

func (*BarometerV2Bricklet) SetWriteFirmwarePointer(pointer uint32) (err error)¶

Parameters:	pointer – Type: uint32, Unit: 1 B, Range: [0 to 2³² - 1]
Returns:	err – Type: error

Sets the firmware pointer for WriteFirmware(). The pointer has to be increased by chunks of size 64. The data is written to flash every 4 chunks (which equals to one page of size 256).

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

func (*BarometerV2Bricklet) WriteFirmware(data [64]uint8) (status uint8, err error)¶

Parameters:	data – Type: [64]uint8, Range: [0 to 255]
Returns:	status – Type: uint8, Range: [0 to 255] err – Type: error

Writes 64 Bytes of firmware at the position as written by SetWriteFirmwarePointer() before. The firmware is written to flash every 4 chunks.

You can only write firmware in bootloader mode.

This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.

func (*BarometerV2Bricklet) WriteUID(uid uint32) (err error)¶

Parameters:	uid – Type: uint32, Range: [0 to 2³² - 1]
Returns:	err – Type: error

Writes a new UID into flash. If you want to set a new UID you have to decode the Base58 encoded UID string into an integer first.

We recommend that you use Brick Viewer to change the UID.

func (*BarometerV2Bricklet) ReadUID() (uid uint32, err error)¶

Returns:	uid – Type: uint32, Range: [0 to 2³² - 1] err – Type: error

Returns the current UID as an integer. Encode as Base58 to get the usual string version.

Constants¶

barometer_v2_bricklet.DeviceIdentifier¶

This constant is used to identify a Barometer Bricklet 2.0.

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

barometer_v2_bricklet.DeviceDisplayName¶: This constant represents the human readable name of a Barometer Bricklet 2.0.