Go - IMU Brick 2.0

This is the description of the Go API bindings for the IMU Brick 2.0. General information and technical specifications for the IMU Brick 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).

Simple

Download (example_simple.go)

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package main

import (
    "fmt"
    "github.com/Tinkerforge/go-api-bindings/imu_v2_brick"
    "github.com/Tinkerforge/go-api-bindings/ipconnection"
)

const ADDR string = "localhost:4223"
const UID string = "XXYYZZ" // Change XXYYZZ to the UID of your IMU Brick 2.0.

func main() {
    ipcon := ipconnection.New()
    defer ipcon.Close()
    imu, _ := imu_v2_brick.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 quaternion.
    w, x, y, z, _ := imu.GetQuaternion()

    fmt.Printf("Quaternion [W]: %f\n", float64(w)/16383.0)
    fmt.Printf("Quaternion [X]: %f\n", float64(x)/16383.0)
    fmt.Printf("Quaternion [Y]: %f\n", float64(y)/16383.0)
    fmt.Printf("Quaternion [Z]: %f\n", float64(z)/16383.0)

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

Callback

Download (example_callback.go)

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package main

import (
    "fmt"
    "github.com/Tinkerforge/go-api-bindings/imu_v2_brick"
    "github.com/Tinkerforge/go-api-bindings/ipconnection"
)

const ADDR string = "localhost:4223"
const UID string = "XXYYZZ" // Change XXYYZZ to the UID of your IMU Brick 2.0.

func main() {
    ipcon := ipconnection.New()
    defer ipcon.Close()
    imu, _ := imu_v2_brick.New(UID, &ipcon) // Create device object.

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

    imu.RegisterQuaternionCallback(func(w int16, x int16, y int16, z int16) {
        fmt.Printf("Quaternion [W]: %f\n", float64(w)/16383.0)
        fmt.Printf("Quaternion [X]: %f\n", float64(x)/16383.0)
        fmt.Printf("Quaternion [Y]: %f\n", float64(y)/16383.0)
        fmt.Printf("Quaternion [Z]: %f\n", float64(z)/16383.0)
        fmt.Println()
    })

    // Set period for quaternion receiver to 0.1s (100ms).
    imu.SetQuaternionPeriod(100)

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

All Data

Download (example_all_data.go)

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package main

import (
    "fmt"
    "github.com/Tinkerforge/go-api-bindings/imu_v2_brick"
    "github.com/Tinkerforge/go-api-bindings/ipconnection"
)

const ADDR string = "localhost:4223"
const UID string = "XXYYZZ" // Change XXYYZZ to the UID of your IMU Brick 2.0.

func main() {
    ipcon := ipconnection.New()
    defer ipcon.Close()
    imu, _ := imu_v2_brick.New(UID, &ipcon) // Create device object.

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

    imu.RegisterAllDataCallback(func(acceleration [3]int16, magneticField [3]int16, angularVelocity [3]int16, eulerAngle [3]int16, quaternion [4]int16, linearAcceleration [3]int16, gravityVector [3]int16, temperature int8, calibrationStatus uint8) {
        fmt.Printf("Acceleration [X]: %f m/s²\n", float64(acceleration[0])/100.0)
        fmt.Printf("Acceleration [Y]: %f m/s²\n", float64(acceleration[1])/100.0)
        fmt.Printf("Acceleration [Z]: %f m/s²\n", float64(acceleration[2])/100.0)
        fmt.Printf("Magnetic Field [X]: %f µT\n", float64(magneticField[0])/16.0)
        fmt.Printf("Magnetic Field [Y]: %f µT\n", float64(magneticField[1])/16.0)
        fmt.Printf("Magnetic Field [Z]: %f µT\n", float64(magneticField[2])/16.0)
        fmt.Printf("Angular Velocity [X]: %f °/s\n", float64(angularVelocity[0])/16.0)
        fmt.Printf("Angular Velocity [Y]: %f °/s\n", float64(angularVelocity[1])/16.0)
        fmt.Printf("Angular Velocity [Z]: %f °/s\n", float64(angularVelocity[2])/16.0)
        fmt.Printf("Euler Angle [X]: %f °\n", float64(eulerAngle[0])/16.0)
        fmt.Printf("Euler Angle [Y]: %f °\n", float64(eulerAngle[1])/16.0)
        fmt.Printf("Euler Angle [Z]: %f °\n", float64(eulerAngle[2])/16.0)
        fmt.Printf("Quaternion [W]: %f\n", float64(quaternion[0])/16383.0)
        fmt.Printf("Quaternion [X]: %f\n", float64(quaternion[1])/16383.0)
        fmt.Printf("Quaternion [Y]: %f\n", float64(quaternion[2])/16383.0)
        fmt.Printf("Quaternion [Z]: %f\n", float64(quaternion[3])/16383.0)
        fmt.Printf("Linear Acceleration [X]: %f m/s²\n", float64(linearAcceleration[0])/100.0)
        fmt.Printf("Linear Acceleration [Y]: %f m/s²\n", float64(linearAcceleration[1])/100.0)
        fmt.Printf("Linear Acceleration [Z]: %f m/s²\n", float64(linearAcceleration[2])/100.0)
        fmt.Printf("Gravity Vector [X]: %f m/s²\n", float64(gravityVector[0])/100.0)
        fmt.Printf("Gravity Vector [Y]: %f m/s²\n", float64(gravityVector[1])/100.0)
        fmt.Printf("Gravity Vector [Z]: %f m/s²\n", float64(gravityVector[2])/100.0)
        fmt.Printf("Temperature: %d °C\n", temperature)
        fmt.Printf("Calibration Status: %b\n", calibrationStatus)
        fmt.Println()
    })

    // Set period for all data receiver to 0.1s (100ms).
    imu.SetAllDataPeriod(100)

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

API

The IMU Brick 2.0 API is defined in the package github.com/Tinkerforge/go-api-bindings/imu_v2_brick

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

  • DeviceErrorSuccess = 0
  • DeviceErrorInvalidParameter = 1
  • DeviceErrorFunctionNotSupported = 2
  • DeviceErrorUnknownError = 3

which correspond to the values returned from Bricks and Bricklets.

All functions listed below are thread-safe.

Basic Functions

func imu_v2_brick.New(uid string, ipcon *IPConnection) (device IMUV2Brick, err error)

Creates a new IMUV2Brick object with the unique device ID uid and adds it to the IPConnection ipcon:

device, err := imu_v2_brick.New("YOUR_DEVICE_UID", &ipcon)

This device object can be used after the IPConnection has been connected (see examples above).

func (*IMUV2Brick) GetOrientation() (heading int16, roll int16, pitch int16, err error)

Returns the current orientation (heading, roll, pitch) of the IMU Brick as independent Euler angles in 1/16 degree. Note that Euler angles always experience a gimbal lock. We recommend that you use quaternions instead, if you need the absolute orientation.

The rotation angle has the following ranges:

  • heading: 0° to 360°
  • roll: -90° to +90°
  • pitch: -180° to +180°

If you want to get the orientation periodically, it is recommended to use the RegisterOrientationCallback callback and set the period with SetOrientationPeriod().

func (*IMUV2Brick) GetLinearAcceleration() (x int16, y int16, z int16, err error)

Returns the linear acceleration of the IMU Brick for the x, y and z axis in 1/100 m/s².

The linear acceleration is the acceleration in each of the three axis of the IMU Brick with the influences of gravity removed.

It is also possible to get the gravity vector with the influence of linear acceleration removed, see GetGravityVector().

If you want to get the linear acceleration periodically, it is recommended to use the RegisterLinearAccelerationCallback callback and set the period with SetLinearAccelerationPeriod().

func (*IMUV2Brick) GetGravityVector() (x int16, y int16, z int16, err error)

Returns the current gravity vector of the IMU Brick for the x, y and z axis in 1/100 m/s².

The gravity vector is the acceleration that occurs due to gravity. Influences of additional linear acceleration are removed.

It is also possible to get the linear acceleration with the influence of gravity removed, see GetLinearAcceleration().

If you want to get the gravity vector periodically, it is recommended to use the RegisterGravityVectorCallback callback and set the period with SetGravityVectorPeriod().

func (*IMUV2Brick) GetQuaternion() (w int16, x int16, y int16, z int16, err error)

Returns the current orientation (w, x, y, z) of the IMU Brick as quaternions.

You have to divide the returns values by 16383 (14 bit) to get the usual range of -1.0 to +1.0 for quaternions.

If you want to get the quaternions periodically, it is recommended to use the RegisterQuaternionCallback callback and set the period with SetQuaternionPeriod().

func (*IMUV2Brick) GetAllData() (acceleration [3]int16, magneticField [3]int16, angularVelocity [3]int16, eulerAngle [3]int16, quaternion [4]int16, linearAcceleration [3]int16, gravityVector [3]int16, temperature int8, calibrationStatus uint8, err error)

Return all of the available data of the IMU Brick.

The calibration status consists of four pairs of two bits. Each pair of bits represents the status of the current calibration.

  • bit 0-1: Magnetometer
  • bit 2-3: Accelerometer
  • bit 4-5: Gyroscope
  • bit 6-7: System

A value of 0 means for "not calibrated" and a value of 3 means "fully calibrated". In your program you should always be able to ignore the calibration status, it is used by the calibration window of the Brick Viewer and it can be ignored after the first calibration. See the documentation in the calibration window for more information regarding the calibration of the IMU Brick.

If you want to get the data periodically, it is recommended to use the RegisterAllDataCallback callback and set the period with SetAllDataPeriod().

func (*IMUV2Brick) LedsOn() (err error)

Turns the orientation and direction LEDs of the IMU Brick on.

func (*IMUV2Brick) LedsOff() (err error)

Turns the orientation and direction LEDs of the IMU Brick off.

func (*IMUV2Brick) AreLedsOn() (leds bool, err error)

Returns true if the orientation and direction LEDs of the IMU Brick are on, false otherwise.

Advanced Functions

func (*IMUV2Brick) GetAcceleration() (x int16, y int16, z int16, err error)

Returns the calibrated acceleration from the accelerometer for the x, y and z axis in 1/100 m/s².

If you want to get the acceleration periodically, it is recommended to use the RegisterAccelerationCallback callback and set the period with SetAccelerationPeriod().

func (*IMUV2Brick) GetMagneticField() (x int16, y int16, z int16, err error)

Returns the calibrated magnetic field from the magnetometer for the x, y and z axis in 1/16 µT (Microtesla).

If you want to get the magnetic field periodically, it is recommended to use the RegisterMagneticFieldCallback callback and set the period with SetMagneticFieldPeriod().

func (*IMUV2Brick) GetAngularVelocity() (x int16, y int16, z int16, err error)

Returns the calibrated angular velocity from the gyroscope for the x, y and z axis in 1/16 °/s.

If you want to get the angular velocity periodically, it is recommended to use the RegisterAngularVelocityCallback acallback nd set the period with SetAngularVelocityPeriod().

func (*IMUV2Brick) GetTemperature() (temperature int8, err error)

Returns the temperature of the IMU Brick. The temperature is given in °C. The temperature is measured in the core of the BNO055 IC, it is not the ambient temperature

func (*IMUV2Brick) SaveCalibration() (calibrationDone bool, err error)

A call of this function saves the current calibration to be used as a starting point for the next restart of continuous calibration of the IMU Brick.

A return value of true means that the calibration could be used and false means that it could not be used (this happens if the calibration status is not "fully calibrated").

This function is used by the calibration window of the Brick Viewer, you should not need to call it in your program.

func (*IMUV2Brick) SetSensorConfiguration(magnetometerRate MagnetometerRate, gyroscopeRange GyroscopeRange, gyroscopeBandwidth GyroscopeBandwidth, accelerometerRange AccelerometerRange, accelerometerBandwidth AccelerometerBandwidth) (err error)

Sets the available sensor configuration for the Magnetometer, Gyroscope and Accelerometer. The Accelerometer Range is user selectable in all fusion modes, all other configurations are auto-controlled in fusion mode.

The default values are:

  • Magnetometer Rate 20Hz
  • Gyroscope Range 2000°/s
  • Gyroscope Bandwidth 32Hz
  • Accelerometer Range +/-4G
  • Accelerometer Bandwidth 62.5Hz

The following constants are available for this function:

  • imu_v2_brick.MagnetometerRate2Hz = 0
  • imu_v2_brick.MagnetometerRate6Hz = 1
  • imu_v2_brick.MagnetometerRate8Hz = 2
  • imu_v2_brick.MagnetometerRate10Hz = 3
  • imu_v2_brick.MagnetometerRate15Hz = 4
  • imu_v2_brick.MagnetometerRate20Hz = 5
  • imu_v2_brick.MagnetometerRate25Hz = 6
  • imu_v2_brick.MagnetometerRate30Hz = 7
  • imu_v2_brick.GyroscopeRange2000DPS = 0
  • imu_v2_brick.GyroscopeRange1000DPS = 1
  • imu_v2_brick.GyroscopeRange500DPS = 2
  • imu_v2_brick.GyroscopeRange250DPS = 3
  • imu_v2_brick.GyroscopeRange125DPS = 4
  • imu_v2_brick.GyroscopeBandwidth523Hz = 0
  • imu_v2_brick.GyroscopeBandwidth230Hz = 1
  • imu_v2_brick.GyroscopeBandwidth116Hz = 2
  • imu_v2_brick.GyroscopeBandwidth47Hz = 3
  • imu_v2_brick.GyroscopeBandwidth23Hz = 4
  • imu_v2_brick.GyroscopeBandwidth12Hz = 5
  • imu_v2_brick.GyroscopeBandwidth64Hz = 6
  • imu_v2_brick.GyroscopeBandwidth32Hz = 7
  • imu_v2_brick.AccelerometerRange2G = 0
  • imu_v2_brick.AccelerometerRange4G = 1
  • imu_v2_brick.AccelerometerRange8G = 2
  • imu_v2_brick.AccelerometerRange16G = 3
  • imu_v2_brick.AccelerometerBandwidth7_81Hz = 0
  • imu_v2_brick.AccelerometerBandwidth15_63Hz = 1
  • imu_v2_brick.AccelerometerBandwidth31_25Hz = 2
  • imu_v2_brick.AccelerometerBandwidth62_5Hz = 3
  • imu_v2_brick.AccelerometerBandwidth125Hz = 4
  • imu_v2_brick.AccelerometerBandwidth250Hz = 5
  • imu_v2_brick.AccelerometerBandwidth500Hz = 6
  • imu_v2_brick.AccelerometerBandwidth1000Hz = 7

New in version 2.0.5 (Firmware).

func (*IMUV2Brick) GetSensorConfiguration() (magnetometerRate MagnetometerRate, gyroscopeRange GyroscopeRange, gyroscopeBandwidth GyroscopeBandwidth, accelerometerRange AccelerometerRange, accelerometerBandwidth AccelerometerBandwidth, err error)

Returns the sensor configuration as set by SetSensorConfiguration().

The following constants are available for this function:

  • imu_v2_brick.MagnetometerRate2Hz = 0
  • imu_v2_brick.MagnetometerRate6Hz = 1
  • imu_v2_brick.MagnetometerRate8Hz = 2
  • imu_v2_brick.MagnetometerRate10Hz = 3
  • imu_v2_brick.MagnetometerRate15Hz = 4
  • imu_v2_brick.MagnetometerRate20Hz = 5
  • imu_v2_brick.MagnetometerRate25Hz = 6
  • imu_v2_brick.MagnetometerRate30Hz = 7
  • imu_v2_brick.GyroscopeRange2000DPS = 0
  • imu_v2_brick.GyroscopeRange1000DPS = 1
  • imu_v2_brick.GyroscopeRange500DPS = 2
  • imu_v2_brick.GyroscopeRange250DPS = 3
  • imu_v2_brick.GyroscopeRange125DPS = 4
  • imu_v2_brick.GyroscopeBandwidth523Hz = 0
  • imu_v2_brick.GyroscopeBandwidth230Hz = 1
  • imu_v2_brick.GyroscopeBandwidth116Hz = 2
  • imu_v2_brick.GyroscopeBandwidth47Hz = 3
  • imu_v2_brick.GyroscopeBandwidth23Hz = 4
  • imu_v2_brick.GyroscopeBandwidth12Hz = 5
  • imu_v2_brick.GyroscopeBandwidth64Hz = 6
  • imu_v2_brick.GyroscopeBandwidth32Hz = 7
  • imu_v2_brick.AccelerometerRange2G = 0
  • imu_v2_brick.AccelerometerRange4G = 1
  • imu_v2_brick.AccelerometerRange8G = 2
  • imu_v2_brick.AccelerometerRange16G = 3
  • imu_v2_brick.AccelerometerBandwidth7_81Hz = 0
  • imu_v2_brick.AccelerometerBandwidth15_63Hz = 1
  • imu_v2_brick.AccelerometerBandwidth31_25Hz = 2
  • imu_v2_brick.AccelerometerBandwidth62_5Hz = 3
  • imu_v2_brick.AccelerometerBandwidth125Hz = 4
  • imu_v2_brick.AccelerometerBandwidth250Hz = 5
  • imu_v2_brick.AccelerometerBandwidth500Hz = 6
  • imu_v2_brick.AccelerometerBandwidth1000Hz = 7

New in version 2.0.5 (Firmware).

func (*IMUV2Brick) SetSensorFusionMode(mode SensorFusion) (err error)

If the fusion mode is turned off, the functions GetAcceleration(), GetMagneticField() and GetAngularVelocity() return uncalibrated and uncompensated sensor data. All other sensor data getters return no data.

Since firmware version 2.0.6 you can also use a fusion mode without magnetometer. In this mode the calculated orientation is relative (with magnetometer it is absolute with respect to the earth). However, the calculation can't be influenced by spurious magnetic fields.

Since firmware version 2.0.13 you can also use a fusion mode without fast magnetometer calibration. This mode is the same as the normal fusion mode, but the fast magnetometer calibration is turned off. So to find the orientation the first time will likely take longer, but small magnetic influences might not affect the automatic calibration as much.

By default sensor fusion is on.

The following constants are available for this function:

  • imu_v2_brick.SensorFusionOff = 0
  • imu_v2_brick.SensorFusionOn = 1
  • imu_v2_brick.SensorFusionOnWithoutMagnetometer = 2
  • imu_v2_brick.SensorFusionOnWithoutFastMagnetometerCalibration = 3

New in version 2.0.5 (Firmware).

func (*IMUV2Brick) GetSensorFusionMode() (mode SensorFusion, err error)

Returns the sensor fusion mode as set by SetSensorFusionMode().

The following constants are available for this function:

  • imu_v2_brick.SensorFusionOff = 0
  • imu_v2_brick.SensorFusionOn = 1
  • imu_v2_brick.SensorFusionOnWithoutMagnetometer = 2
  • imu_v2_brick.SensorFusionOnWithoutFastMagnetometerCalibration = 3

New in version 2.0.5 (Firmware).

func (*IMUV2Brick) GetAPIVersion() (apiVersion [3]uint8, err error)

Returns the version of the API definition (major, minor, revision) 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 (*IMUV2Brick) GetResponseExpected(functionId Function) (responseExpected bool, err 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 send and errors are silently ignored, because they cannot be detected.

The following constants are available for this function:

  • imu_v2_brick.FunctionLedsOn = 10
  • imu_v2_brick.FunctionLedsOff = 11
  • imu_v2_brick.FunctionSetAccelerationPeriod = 14
  • imu_v2_brick.FunctionSetMagneticFieldPeriod = 16
  • imu_v2_brick.FunctionSetAngularVelocityPeriod = 18
  • imu_v2_brick.FunctionSetTemperaturePeriod = 20
  • imu_v2_brick.FunctionSetOrientationPeriod = 22
  • imu_v2_brick.FunctionSetLinearAccelerationPeriod = 24
  • imu_v2_brick.FunctionSetGravityVectorPeriod = 26
  • imu_v2_brick.FunctionSetQuaternionPeriod = 28
  • imu_v2_brick.FunctionSetAllDataPeriod = 30
  • imu_v2_brick.FunctionSetSensorConfiguration = 41
  • imu_v2_brick.FunctionSetSensorFusionMode = 43
  • imu_v2_brick.FunctionSetSPITFPBaudrateConfig = 231
  • imu_v2_brick.FunctionSetSPITFPBaudrate = 234
  • imu_v2_brick.FunctionEnableStatusLED = 238
  • imu_v2_brick.FunctionDisableStatusLED = 239
  • imu_v2_brick.FunctionReset = 243
func (*IMUV2Brick) SetResponseExpected(functionId Function, responseExpected bool) (err 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.

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:

  • imu_v2_brick.FunctionLedsOn = 10
  • imu_v2_brick.FunctionLedsOff = 11
  • imu_v2_brick.FunctionSetAccelerationPeriod = 14
  • imu_v2_brick.FunctionSetMagneticFieldPeriod = 16
  • imu_v2_brick.FunctionSetAngularVelocityPeriod = 18
  • imu_v2_brick.FunctionSetTemperaturePeriod = 20
  • imu_v2_brick.FunctionSetOrientationPeriod = 22
  • imu_v2_brick.FunctionSetLinearAccelerationPeriod = 24
  • imu_v2_brick.FunctionSetGravityVectorPeriod = 26
  • imu_v2_brick.FunctionSetQuaternionPeriod = 28
  • imu_v2_brick.FunctionSetAllDataPeriod = 30
  • imu_v2_brick.FunctionSetSensorConfiguration = 41
  • imu_v2_brick.FunctionSetSensorFusionMode = 43
  • imu_v2_brick.FunctionSetSPITFPBaudrateConfig = 231
  • imu_v2_brick.FunctionSetSPITFPBaudrate = 234
  • imu_v2_brick.FunctionEnableStatusLED = 238
  • imu_v2_brick.FunctionDisableStatusLED = 239
  • imu_v2_brick.FunctionReset = 243
func (*IMUV2Brick) SetResponseExpectedAll(responseExpected bool) (err error)

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

func (*IMUV2Brick) SetSPITFPBaudrateConfig(enableDynamicBaudrate bool, minimumDynamicBaudrate uint32) (err error)

The SPITF protocol can be used with a dynamic baudrate. If the dynamic baudrate is enabled, the Brick will try to adapt the baudrate for the communication between Bricks and Bricklets according to the amount of data that is transferred.

The baudrate will be increased exponentially if lots of data is send/received and decreased linearly if little data is send/received.

This lowers the baudrate in applications where little data is transferred (e.g. a weather station) and increases the robustness. If there is lots of data to transfer (e.g. Thermal Imaging Bricklet) it automatically increases the baudrate as needed.

In cases where some data has to transferred as fast as possible every few seconds (e.g. RS485 Bricklet with a high baudrate but small payload) you may want to turn the dynamic baudrate off to get the highest possible performance.

The maximum value of the baudrate can be set per port with the function SetSPITFPBaudrate(). If the dynamic baudrate is disabled, the baudrate as set by SetSPITFPBaudrate() will be used statically.

The minimum dynamic baudrate has a value range of 400000 to 2000000 baud.

By default dynamic baudrate is enabled and the minimum dynamic baudrate is 400000.

New in version 2.0.10 (Firmware).

func (*IMUV2Brick) GetSPITFPBaudrateConfig() (enableDynamicBaudrate bool, minimumDynamicBaudrate uint32, err error)

Returns the baudrate config, see SetSPITFPBaudrateConfig().

New in version 2.0.10 (Firmware).

func (*IMUV2Brick) GetSendTimeoutCount(communicationMethod CommunicationMethod) (timeoutCount uint32, err error)

Returns the timeout count for the different communication methods.

The methods 0-2 are available for all Bricks, 3-7 only for Master Bricks.

This function is mostly used for debugging during development, in normal operation the counters should nearly always stay at 0.

The following constants are available for this function:

  • imu_v2_brick.CommunicationMethodNone = 0
  • imu_v2_brick.CommunicationMethodUSB = 1
  • imu_v2_brick.CommunicationMethodSPIStack = 2
  • imu_v2_brick.CommunicationMethodChibi = 3
  • imu_v2_brick.CommunicationMethodRS485 = 4
  • imu_v2_brick.CommunicationMethodWIFI = 5
  • imu_v2_brick.CommunicationMethodEthernet = 6
  • imu_v2_brick.CommunicationMethodWIFIV2 = 7

New in version 2.0.7 (Firmware).

func (*IMUV2Brick) SetSPITFPBaudrate(brickletPort rune, baudrate uint32) (err error)

Sets the baudrate for a specific Bricklet port ('a' - 'd'). The baudrate can be in the range 400000 to 2000000.

If you want to increase the throughput of Bricklets you can increase the baudrate. If you get a high error count because of high interference (see GetSPITFPErrorCount()) you can decrease the baudrate.

If the dynamic baudrate feature is enabled, the baudrate set by this function corresponds to the maximum baudrate (see SetSPITFPBaudrateConfig()).

Regulatory testing is done with the default baudrate. If CE compatibility or similar is necessary in you applications we recommend to not change the baudrate.

The default baudrate for all ports is 1400000.

New in version 2.0.5 (Firmware).

func (*IMUV2Brick) GetSPITFPBaudrate(brickletPort rune) (baudrate uint32, err error)

Returns the baudrate for a given Bricklet port, see SetSPITFPBaudrate().

New in version 2.0.5 (Firmware).

func (*IMUV2Brick) GetSPITFPErrorCount(brickletPort rune) (errorCountACKChecksum uint32, errorCountMessageChecksum uint32, errorCountFrame uint32, errorCountOverflow uint32, err 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 Brick side. All Bricklets have a similar function that returns the errors on the Bricklet side.

New in version 2.0.5 (Firmware).

func (*IMUV2Brick) EnableStatusLED() (err error)

Enables the status LED.

The status LED is the blue LED next to the USB connector. If enabled is is on and it flickers if data is transfered. If disabled it is always off.

The default state is enabled.

func (*IMUV2Brick) DisableStatusLED() (err error)

Disables the status LED.

The status LED is the blue LED next to the USB connector. If enabled is is on and it flickers if data is transfered. If disabled it is always off.

The default state is enabled.

func (*IMUV2Brick) IsStatusLEDEnabled() (enabled bool, err error)

Returns true if the status LED is enabled, false otherwise.

func (*IMUV2Brick) GetProtocol1BrickletName(port rune) (protocolVersion uint8, firmwareVersion [3]uint8, name string, err error)

Returns the firmware and protocol version and the name of the Bricklet for a given port.

This functions sole purpose is to allow automatic flashing of v1.x.y Bricklet plugins.

func (*IMUV2Brick) GetChipTemperature() (temperature int16, err error)

Returns the temperature in °C/10 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 an accuracy of ±15%. Practically it is only useful as an indicator for temperature changes.

func (*IMUV2Brick) Reset() (err error)

Calling this function will reset the Brick. Calling this function on a Brick inside of a stack will reset the whole stack.

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

func (*IMUV2Brick) GetIdentity() (uid string, connectedUid string, position rune, hardwareVersion [3]uint8, firmwareVersion [3]uint8, deviceIdentifier uint16, err error)

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

The position can be '0'-'8' (stack position).

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

Callback Configuration Functions

func (*IMUV2Brick) SetAccelerationPeriod(period uint32) (err error)

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

The default value is 0.

func (*IMUV2Brick) GetAccelerationPeriod() (period uint32, err error)

Returns the period as set by SetAccelerationPeriod().

func (*IMUV2Brick) SetMagneticFieldPeriod(period uint32) (err error)

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

func (*IMUV2Brick) GetMagneticFieldPeriod() (period uint32, err error)

Returns the period as set by SetMagneticFieldPeriod().

func (*IMUV2Brick) SetAngularVelocityPeriod(period uint32) (err error)

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

func (*IMUV2Brick) GetAngularVelocityPeriod() (period uint32, err error)

Returns the period as set by SetAngularVelocityPeriod().

func (*IMUV2Brick) SetTemperaturePeriod(period uint32) (err error)

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

func (*IMUV2Brick) GetTemperaturePeriod() (period uint32, err error)

Returns the period as set by SetTemperaturePeriod().

func (*IMUV2Brick) SetOrientationPeriod(period uint32) (err error)

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

func (*IMUV2Brick) GetOrientationPeriod() (period uint32, err error)

Returns the period as set by SetOrientationPeriod().

func (*IMUV2Brick) SetLinearAccelerationPeriod(period uint32) (err error)

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

func (*IMUV2Brick) GetLinearAccelerationPeriod() (period uint32, err error)

Returns the period as set by SetLinearAccelerationPeriod().

func (*IMUV2Brick) SetGravityVectorPeriod(period uint32) (err error)

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

func (*IMUV2Brick) GetGravityVectorPeriod() (period uint32, err error)

Returns the period as set by SetGravityVectorPeriod().

func (*IMUV2Brick) SetQuaternionPeriod(period uint32) (err error)

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

func (*IMUV2Brick) GetQuaternionPeriod() (period uint32, err error)

Returns the period as set by SetQuaternionPeriod().

func (*IMUV2Brick) SetAllDataPeriod(period uint32) (err error)

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

func (*IMUV2Brick) GetAllDataPeriod() (period uint32, err error)

Returns the period as set by SetAllDataPeriod().

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.

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 (*IMUV2Brick) RegisterAccelerationCallback(func(x int16, y int16, z int16)) (registrationId uint64)

A callback can be registered for this event with the RegisterAccelerationCallback() function. This function returns the ID of the registered callback. An added callback can be removed with the DeregisterAccelerationCallback(registrationId uint64) function.

This callback is triggered periodically with the period that is set by SetAccelerationPeriod(). The callback parameters are the acceleration for the x, y and z axis.

func (*IMUV2Brick) RegisterMagneticFieldCallback(func(x int16, y int16, z int16)) (registrationId uint64)

A callback can be registered for this event with the RegisterMagneticFieldCallback() function. This function returns the ID of the registered callback. An added callback can be removed with the DeregisterMagneticFieldCallback(registrationId uint64) function.

This callback is triggered periodically with the period that is set by SetMagneticFieldPeriod(). The callback parameters are the magnetic field for the x, y and z axis.

func (*IMUV2Brick) RegisterAngularVelocityCallback(func(x int16, y int16, z int16)) (registrationId uint64)

A callback can be registered for this event with the RegisterAngularVelocityCallback() function. This function returns the ID of the registered callback. An added callback can be removed with the DeregisterAngularVelocityCallback(registrationId uint64) function.

This callback is triggered periodically with the period that is set by SetAngularVelocityPeriod(). The callback parameters are the angular velocity for the x, y and z axis.

func (*IMUV2Brick) RegisterTemperatureCallback(func(temperature int8)) (registrationId uint64)

A callback can be registered for this event with the RegisterTemperatureCallback() function. This function returns the ID of the registered callback. An added callback can be removed with the DeregisterTemperatureCallback(registrationId uint64) function.

This callback is triggered periodically with the period that is set by SetTemperaturePeriod(). The callback parameter is the temperature.

func (*IMUV2Brick) RegisterLinearAccelerationCallback(func(x int16, y int16, z int16)) (registrationId uint64)

A callback can be registered for this event with the RegisterLinearAccelerationCallback() function. This function returns the ID of the registered callback. An added callback can be removed with the DeregisterLinearAccelerationCallback(registrationId uint64) function.

This callback is triggered periodically with the period that is set by SetLinearAccelerationPeriod(). The callback parameters are the linear acceleration for the x, y and z axis.

func (*IMUV2Brick) RegisterGravityVectorCallback(func(x int16, y int16, z int16)) (registrationId uint64)

A callback can be registered for this event with the RegisterGravityVectorCallback() function. This function returns the ID of the registered callback. An added callback can be removed with the DeregisterGravityVectorCallback(registrationId uint64) function.

This callback is triggered periodically with the period that is set by SetGravityVectorPeriod(). The callback parameters gravity vector for the x, y and z axis.

func (*IMUV2Brick) RegisterOrientationCallback(func(heading int16, roll int16, pitch int16)) (registrationId uint64)

A callback can be registered for this event with the RegisterOrientationCallback() function. This function returns the ID of the registered callback. An added callback can be removed with the DeregisterOrientationCallback(registrationId uint64) function.

This callback is triggered periodically with the period that is set by SetOrientationPeriod(). The callback parameters are the orientation (heading (yaw), roll, pitch) of the IMU Brick in Euler angles. See GetOrientation() for details.

func (*IMUV2Brick) RegisterQuaternionCallback(func(w int16, x int16, y int16, z int16)) (registrationId uint64)

A callback can be registered for this event with the RegisterQuaternionCallback() function. This function returns the ID of the registered callback. An added callback can be removed with the DeregisterQuaternionCallback(registrationId uint64) function.

This callback is triggered periodically with the period that is set by SetQuaternionPeriod(). The callback parameters are the orientation (x, y, z, w) of the IMU Brick in quaternions. See GetQuaternion() for details.

func (*IMUV2Brick) RegisterAllDataCallback(func(acceleration [3]int16, magneticField [3]int16, angularVelocity [3]int16, eulerAngle [3]int16, quaternion [4]int16, linearAcceleration [3]int16, gravityVector [3]int16, temperature int8, calibrationStatus uint8)) (registrationId uint64)

A callback can be registered for this event with the RegisterAllDataCallback() function. This function returns the ID of the registered callback. An added callback can be removed with the DeregisterAllDataCallback(registrationId uint64) function.

This callback is triggered periodically with the period that is set by SetAllDataPeriod(). The callback parameters are as for GetAllData().

Constants

imu_v2_brick.DeviceIdentifier

This constant is used to identify a IMU Brick 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.

imu_v2_brick.DeviceDisplayName

This constant represents the human readable name of a IMU Brick 2.0.