Delphi/Lazarus - IMU Brick 2.0

This is the description of the Delphi/Lazarus 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 Delphi/Lazarus API bindings is part of their general description.

Examples

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

Simple

Download (ExampleSimple.pas)

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program ExampleSimple;

{$ifdef MSWINDOWS}{$apptype CONSOLE}{$endif}
{$ifdef FPC}{$mode OBJFPC}{$H+}{$endif}

uses
  SysUtils, IPConnection, BrickIMUV2;

type
  TExample = class
  private
    ipcon: TIPConnection;
    imu: TBrickIMUV2;
  public
    procedure Execute;
  end;

const
  HOST = 'localhost';
  PORT = 4223;
  UID = 'XXYYZZ'; { Change XXYYZZ to the UID of your IMU Brick 2.0 }

var
  e: TExample;

procedure TExample.Execute;
var w, x, y, z: smallint;
begin
  { Create IP connection }
  ipcon := TIPConnection.Create;

  { Create device object }
  imu := TBrickIMUV2.Create(UID, ipcon);

  { Connect to brickd }
  ipcon.Connect(HOST, PORT);
  { Don't use device before ipcon is connected }

  { Get current quaternion }
  imu.GetQuaternion(w, x, y, z);

  WriteLn(Format('Quaternion [W]: %f', [w/16383.0]));
  WriteLn(Format('Quaternion [X]: %f', [x/16383.0]));
  WriteLn(Format('Quaternion [Y]: %f', [y/16383.0]));
  WriteLn(Format('Quaternion [Z]: %f', [z/16383.0]));

  WriteLn('Press key to exit');
  ReadLn;
  ipcon.Destroy; { Calls ipcon.Disconnect internally }
end;

begin
  e := TExample.Create;
  e.Execute;
  e.Destroy;
end.

Callback

Download (ExampleCallback.pas)

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program ExampleCallback;

{$ifdef MSWINDOWS}{$apptype CONSOLE}{$endif}
{$ifdef FPC}{$mode OBJFPC}{$H+}{$endif}

uses
  SysUtils, IPConnection, BrickIMUV2;

type
  TExample = class
  private
    ipcon: TIPConnection;
    imu: TBrickIMUV2;
  public
    procedure QuaternionCB(sender: TBrickIMUV2; const w: smallint; const x: smallint;
                           const y: smallint; const z: smallint);
    procedure Execute;
  end;

const
  HOST = 'localhost';
  PORT = 4223;
  UID = 'XXYYZZ'; { Change XXYYZZ to the UID of your IMU Brick 2.0 }

var
  e: TExample;

{ Callback procedure for quaternion callback }
procedure TExample.QuaternionCB(sender: TBrickIMUV2; const w: smallint; const x: smallint;
                                const y: smallint; const z: smallint);
begin
  WriteLn(Format('Quaternion [W]: %f', [w/16383.0]));
  WriteLn(Format('Quaternion [X]: %f', [x/16383.0]));
  WriteLn(Format('Quaternion [Y]: %f', [y/16383.0]));
  WriteLn(Format('Quaternion [Z]: %f', [z/16383.0]));
  WriteLn('');
end;

procedure TExample.Execute;
begin
  { Create IP connection }
  ipcon := TIPConnection.Create;

  { Create device object }
  imu := TBrickIMUV2.Create(UID, ipcon);

  { Connect to brickd }
  ipcon.Connect(HOST, PORT);
  { Don't use device before ipcon is connected }

  { Register quaternion callback to procedure QuaternionCB }
  imu.OnQuaternion := {$ifdef FPC}@{$endif}QuaternionCB;

  { Set period for quaternion callback to 0.1s (100ms) }
  imu.SetQuaternionPeriod(100);

  WriteLn('Press key to exit');
  ReadLn;
  ipcon.Destroy; { Calls ipcon.Disconnect internally }
end;

begin
  e := TExample.Create;
  e.Execute;
  e.Destroy;
end.

All Data

Download (ExampleAllData.pas)

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program ExampleAllData;

{$ifdef MSWINDOWS}{$apptype CONSOLE}{$endif}
{$ifdef FPC}{$mode OBJFPC}{$H+}{$endif}

uses
  SysUtils, IPConnection, BrickIMUV2;

type
  TExample = class
  private
    ipcon: TIPConnection;
    imu: TBrickIMUV2;
  public
    procedure AllDataCB(sender: TBrickIMUV2; const acceleration: TArray0To2OfInt16;
                        const magneticField: TArray0To2OfInt16;
                        const angularVelocity: TArray0To2OfInt16;
                        const eulerAngle: TArray0To2OfInt16;
                        const quaternion: TArray0To3OfInt16;
                        const linearAcceleration: TArray0To2OfInt16;
                        const gravityVector: TArray0To2OfInt16;
                        const temperature: shortint; const calibrationStatus: byte);
    procedure Execute;
  end;

const
  HOST = 'localhost';
  PORT = 4223;
  UID = 'XXYYZZ'; { Change XXYYZZ to the UID of your IMU Brick 2.0 }

var
  e: TExample;

{ Callback procedure for all data callback }
procedure TExample.AllDataCB(sender: TBrickIMUV2; const acceleration: TArray0To2OfInt16;
                             const magneticField: TArray0To2OfInt16;
                             const angularVelocity: TArray0To2OfInt16;
                             const eulerAngle: TArray0To2OfInt16;
                             const quaternion: TArray0To3OfInt16;
                             const linearAcceleration: TArray0To2OfInt16;
                             const gravityVector: TArray0To2OfInt16;
                             const temperature: shortint; const calibrationStatus: byte);
begin
  WriteLn(Format('Acceleration [X]: %f m/s²', [acceleration[0]/100.0]));
  WriteLn(Format('Acceleration [Y]: %f m/s²', [acceleration[1]/100.0]));
  WriteLn(Format('Acceleration [Z]: %f m/s²', [acceleration[2]/100.0]));
  WriteLn(Format('Magnetic Field [X]: %f µT', [magneticField[0]/16.0]));
  WriteLn(Format('Magnetic Field [Y]: %f µT', [magneticField[1]/16.0]));
  WriteLn(Format('Magnetic Field [Z]: %f µT', [magneticField[2]/16.0]));
  WriteLn(Format('Angular Velocity [X]: %f °/s', [angularVelocity[0]/16.0]));
  WriteLn(Format('Angular Velocity [Y]: %f °/s', [angularVelocity[1]/16.0]));
  WriteLn(Format('Angular Velocity [Z]: %f °/s', [angularVelocity[2]/16.0]));
  WriteLn(Format('Euler Angle [X]: %f °', [eulerAngle[0]/16.0]));
  WriteLn(Format('Euler Angle [Y]: %f °', [eulerAngle[1]/16.0]));
  WriteLn(Format('Euler Angle [Z]: %f °', [eulerAngle[2]/16.0]));
  WriteLn(Format('Quaternion [W]: %f', [quaternion[0]/16383.0]));
  WriteLn(Format('Quaternion [X]: %f', [quaternion[1]/16383.0]));
  WriteLn(Format('Quaternion [Y]: %f', [quaternion[2]/16383.0]));
  WriteLn(Format('Quaternion [Z]: %f', [quaternion[3]/16383.0]));
  WriteLn(Format('Linear Acceleration [X]: %f m/s²', [linearAcceleration[0]/100.0]));
  WriteLn(Format('Linear Acceleration [Y]: %f m/s²', [linearAcceleration[1]/100.0]));
  WriteLn(Format('Linear Acceleration [Z]: %f m/s²', [linearAcceleration[2]/100.0]));
  WriteLn(Format('Gravity Vector [X]: %f m/s²', [gravityVector[0]/100.0]));
  WriteLn(Format('Gravity Vector [Y]: %f m/s²', [gravityVector[1]/100.0]));
  WriteLn(Format('Gravity Vector [Z]: %f m/s²', [gravityVector[2]/100.0]));
  WriteLn(Format('Temperature: %d °C', [temperature]));
  WriteLn(Format('Calibration Status: %d', [calibrationStatus]));
  WriteLn('');
end;

procedure TExample.Execute;
begin
  { Create IP connection }
  ipcon := TIPConnection.Create;

  { Create device object }
  imu := TBrickIMUV2.Create(UID, ipcon);

  { Connect to brickd }
  ipcon.Connect(HOST, PORT);
  { Don't use device before ipcon is connected }

  { Register all data callback to procedure AllDataCB }
  imu.OnAllData := {$ifdef FPC}@{$endif}AllDataCB;

  { Set period for all data callback to 0.1s (100ms) }
  imu.SetAllDataPeriod(100);

  WriteLn('Press key to exit');
  ReadLn;
  ipcon.Destroy; { Calls ipcon.Disconnect internally }
end;

begin
  e := TExample.Create;
  e.Execute;
  e.Destroy;
end.

API

Since Delphi does not support multiple return values directly, we use the out keyword to return multiple values from a function.

All functions and procedures listed below are thread-safe.

Basic Functions

constructor TBrickIMUV2.Create(const uid: string; ipcon: TIPConnection)

Creates an object with the unique device ID uid:

imuV2 := TBrickIMUV2.Create('YOUR_DEVICE_UID', ipcon);

This object can then be used after the IP Connection is connected (see examples above).

procedure TBrickIMUV2.GetOrientation(out heading: smallint; out roll: smallint; out pitch: smallint)

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 OnOrientation callback and set the period with SetOrientationPeriod.

procedure TBrickIMUV2.GetLinearAcceleration(out x: smallint; out y: smallint; out z: smallint)

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 OnLinearAcceleration callback and set the period with SetLinearAccelerationPeriod.

procedure TBrickIMUV2.GetGravityVector(out x: smallint; out y: smallint; out z: smallint)

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 OnGravityVector callback and set the period with SetGravityVectorPeriod.

procedure TBrickIMUV2.GetQuaternion(out w: smallint; out x: smallint; out y: smallint; out z: smallint)

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 OnQuaternion callback and set the period with SetQuaternionPeriod.

procedure TBrickIMUV2.GetAllData(out acceleration: array [0..2] of smallint; out magneticField: array [0..2] of smallint; out angularVelocity: array [0..2] of smallint; out eulerAngle: array [0..2] of smallint; out quaternion: array [0..3] of smallint; out linearAcceleration: array [0..2] of smallint; out gravityVector: array [0..2] of smallint; out temperature: shortint; out calibrationStatus: byte)

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 OnAllData callback and set the period with SetAllDataPeriod.

procedure TBrickIMUV2.LedsOn

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

procedure TBrickIMUV2.LedsOff

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

function TBrickIMUV2.AreLedsOn: boolean

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

Advanced Functions

procedure TBrickIMUV2.GetAcceleration(out x: smallint; out y: smallint; out z: smallint)

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 OnAcceleration callback and set the period with SetAccelerationPeriod.

procedure TBrickIMUV2.GetMagneticField(out x: smallint; out y: smallint; out z: smallint)

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 OnMagneticField callback and set the period with SetMagneticFieldPeriod.

procedure TBrickIMUV2.GetAngularVelocity(out x: smallint; out y: smallint; out z: smallint)

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 OnAngularVelocity acallback nd set the period with SetAngularVelocityPeriod.

function TBrickIMUV2.GetTemperature: shortint

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

function TBrickIMUV2.SaveCalibration: boolean

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.

procedure TBrickIMUV2.SetSensorConfiguration(const magnetometerRate: byte; const gyroscopeRange: byte; const gyroscopeBandwidth: byte; const accelerometerRange: byte; const accelerometerBandwidth: byte)

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:

  • BRICK_IMU_V2_MAGNETOMETER_RATE_2HZ = 0
  • BRICK_IMU_V2_MAGNETOMETER_RATE_6HZ = 1
  • BRICK_IMU_V2_MAGNETOMETER_RATE_8HZ = 2
  • BRICK_IMU_V2_MAGNETOMETER_RATE_10HZ = 3
  • BRICK_IMU_V2_MAGNETOMETER_RATE_15HZ = 4
  • BRICK_IMU_V2_MAGNETOMETER_RATE_20HZ = 5
  • BRICK_IMU_V2_MAGNETOMETER_RATE_25HZ = 6
  • BRICK_IMU_V2_MAGNETOMETER_RATE_30HZ = 7
  • BRICK_IMU_V2_GYROSCOPE_RANGE_2000DPS = 0
  • BRICK_IMU_V2_GYROSCOPE_RANGE_1000DPS = 1
  • BRICK_IMU_V2_GYROSCOPE_RANGE_500DPS = 2
  • BRICK_IMU_V2_GYROSCOPE_RANGE_250DPS = 3
  • BRICK_IMU_V2_GYROSCOPE_RANGE_125DPS = 4
  • BRICK_IMU_V2_GYROSCOPE_BANDWIDTH_523HZ = 0
  • BRICK_IMU_V2_GYROSCOPE_BANDWIDTH_230HZ = 1
  • BRICK_IMU_V2_GYROSCOPE_BANDWIDTH_116HZ = 2
  • BRICK_IMU_V2_GYROSCOPE_BANDWIDTH_47HZ = 3
  • BRICK_IMU_V2_GYROSCOPE_BANDWIDTH_23HZ = 4
  • BRICK_IMU_V2_GYROSCOPE_BANDWIDTH_12HZ = 5
  • BRICK_IMU_V2_GYROSCOPE_BANDWIDTH_64HZ = 6
  • BRICK_IMU_V2_GYROSCOPE_BANDWIDTH_32HZ = 7
  • BRICK_IMU_V2_ACCELEROMETER_RANGE_2G = 0
  • BRICK_IMU_V2_ACCELEROMETER_RANGE_4G = 1
  • BRICK_IMU_V2_ACCELEROMETER_RANGE_8G = 2
  • BRICK_IMU_V2_ACCELEROMETER_RANGE_16G = 3
  • BRICK_IMU_V2_ACCELEROMETER_BANDWIDTH_7_81HZ = 0
  • BRICK_IMU_V2_ACCELEROMETER_BANDWIDTH_15_63HZ = 1
  • BRICK_IMU_V2_ACCELEROMETER_BANDWIDTH_31_25HZ = 2
  • BRICK_IMU_V2_ACCELEROMETER_BANDWIDTH_62_5HZ = 3
  • BRICK_IMU_V2_ACCELEROMETER_BANDWIDTH_125HZ = 4
  • BRICK_IMU_V2_ACCELEROMETER_BANDWIDTH_250HZ = 5
  • BRICK_IMU_V2_ACCELEROMETER_BANDWIDTH_500HZ = 6
  • BRICK_IMU_V2_ACCELEROMETER_BANDWIDTH_1000HZ = 7

New in version 2.0.5 (Firmware).

procedure TBrickIMUV2.GetSensorConfiguration(out magnetometerRate: byte; out gyroscopeRange: byte; out gyroscopeBandwidth: byte; out accelerometerRange: byte; out accelerometerBandwidth: byte)

Returns the sensor configuration as set by SetSensorConfiguration.

The following constants are available for this function:

  • BRICK_IMU_V2_MAGNETOMETER_RATE_2HZ = 0
  • BRICK_IMU_V2_MAGNETOMETER_RATE_6HZ = 1
  • BRICK_IMU_V2_MAGNETOMETER_RATE_8HZ = 2
  • BRICK_IMU_V2_MAGNETOMETER_RATE_10HZ = 3
  • BRICK_IMU_V2_MAGNETOMETER_RATE_15HZ = 4
  • BRICK_IMU_V2_MAGNETOMETER_RATE_20HZ = 5
  • BRICK_IMU_V2_MAGNETOMETER_RATE_25HZ = 6
  • BRICK_IMU_V2_MAGNETOMETER_RATE_30HZ = 7
  • BRICK_IMU_V2_GYROSCOPE_RANGE_2000DPS = 0
  • BRICK_IMU_V2_GYROSCOPE_RANGE_1000DPS = 1
  • BRICK_IMU_V2_GYROSCOPE_RANGE_500DPS = 2
  • BRICK_IMU_V2_GYROSCOPE_RANGE_250DPS = 3
  • BRICK_IMU_V2_GYROSCOPE_RANGE_125DPS = 4
  • BRICK_IMU_V2_GYROSCOPE_BANDWIDTH_523HZ = 0
  • BRICK_IMU_V2_GYROSCOPE_BANDWIDTH_230HZ = 1
  • BRICK_IMU_V2_GYROSCOPE_BANDWIDTH_116HZ = 2
  • BRICK_IMU_V2_GYROSCOPE_BANDWIDTH_47HZ = 3
  • BRICK_IMU_V2_GYROSCOPE_BANDWIDTH_23HZ = 4
  • BRICK_IMU_V2_GYROSCOPE_BANDWIDTH_12HZ = 5
  • BRICK_IMU_V2_GYROSCOPE_BANDWIDTH_64HZ = 6
  • BRICK_IMU_V2_GYROSCOPE_BANDWIDTH_32HZ = 7
  • BRICK_IMU_V2_ACCELEROMETER_RANGE_2G = 0
  • BRICK_IMU_V2_ACCELEROMETER_RANGE_4G = 1
  • BRICK_IMU_V2_ACCELEROMETER_RANGE_8G = 2
  • BRICK_IMU_V2_ACCELEROMETER_RANGE_16G = 3
  • BRICK_IMU_V2_ACCELEROMETER_BANDWIDTH_7_81HZ = 0
  • BRICK_IMU_V2_ACCELEROMETER_BANDWIDTH_15_63HZ = 1
  • BRICK_IMU_V2_ACCELEROMETER_BANDWIDTH_31_25HZ = 2
  • BRICK_IMU_V2_ACCELEROMETER_BANDWIDTH_62_5HZ = 3
  • BRICK_IMU_V2_ACCELEROMETER_BANDWIDTH_125HZ = 4
  • BRICK_IMU_V2_ACCELEROMETER_BANDWIDTH_250HZ = 5
  • BRICK_IMU_V2_ACCELEROMETER_BANDWIDTH_500HZ = 6
  • BRICK_IMU_V2_ACCELEROMETER_BANDWIDTH_1000HZ = 7

New in version 2.0.5 (Firmware).

procedure TBrickIMUV2.SetSensorFusionMode(const mode: byte)

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:

  • BRICK_IMU_V2_SENSOR_FUSION_OFF = 0
  • BRICK_IMU_V2_SENSOR_FUSION_ON = 1
  • BRICK_IMU_V2_SENSOR_FUSION_ON_WITHOUT_MAGNETOMETER = 2
  • BRICK_IMU_V2_SENSOR_FUSION_ON_WITHOUT_FAST_MAGNETOMETER_CALIBRATION = 3

New in version 2.0.5 (Firmware).

function TBrickIMUV2.GetSensorFusionMode: byte

Returns the sensor fusion mode as set by SetSensorFusionMode.

The following constants are available for this function:

  • BRICK_IMU_V2_SENSOR_FUSION_OFF = 0
  • BRICK_IMU_V2_SENSOR_FUSION_ON = 1
  • BRICK_IMU_V2_SENSOR_FUSION_ON_WITHOUT_MAGNETOMETER = 2
  • BRICK_IMU_V2_SENSOR_FUSION_ON_WITHOUT_FAST_MAGNETOMETER_CALIBRATION = 3

New in version 2.0.5 (Firmware).

function TBrickIMUV2.GetAPIVersion: array [0..2] of byte

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.

function TBrickIMUV2.GetResponseExpected(const functionId: byte): 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.

See SetResponseExpected for the list of function ID constants available for this function.

procedure TBrickIMUV2.SetResponseExpected(const functionId: byte; const responseExpected: 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 function ID constants are available for this function:

  • BRICK_IMU_V2_FUNCTION_LEDS_ON = 10
  • BRICK_IMU_V2_FUNCTION_LEDS_OFF = 11
  • BRICK_IMU_V2_FUNCTION_SET_ACCELERATION_PERIOD = 14
  • BRICK_IMU_V2_FUNCTION_SET_MAGNETIC_FIELD_PERIOD = 16
  • BRICK_IMU_V2_FUNCTION_SET_ANGULAR_VELOCITY_PERIOD = 18
  • BRICK_IMU_V2_FUNCTION_SET_TEMPERATURE_PERIOD = 20
  • BRICK_IMU_V2_FUNCTION_SET_ORIENTATION_PERIOD = 22
  • BRICK_IMU_V2_FUNCTION_SET_LINEAR_ACCELERATION_PERIOD = 24
  • BRICK_IMU_V2_FUNCTION_SET_GRAVITY_VECTOR_PERIOD = 26
  • BRICK_IMU_V2_FUNCTION_SET_QUATERNION_PERIOD = 28
  • BRICK_IMU_V2_FUNCTION_SET_ALL_DATA_PERIOD = 30
  • BRICK_IMU_V2_FUNCTION_SET_SENSOR_CONFIGURATION = 41
  • BRICK_IMU_V2_FUNCTION_SET_SENSOR_FUSION_MODE = 43
  • BRICK_IMU_V2_FUNCTION_SET_SPITFP_BAUDRATE_CONFIG = 231
  • BRICK_IMU_V2_FUNCTION_SET_SPITFP_BAUDRATE = 234
  • BRICK_IMU_V2_FUNCTION_ENABLE_STATUS_LED = 238
  • BRICK_IMU_V2_FUNCTION_DISABLE_STATUS_LED = 239
  • BRICK_IMU_V2_FUNCTION_RESET = 243
procedure TBrickIMUV2.SetResponseExpectedAll(const responseExpected: boolean)

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

procedure TBrickIMUV2.SetSPITFPBaudrateConfig(const enableDynamicBaudrate: boolean; const minimumDynamicBaudrate: longword)

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).

procedure TBrickIMUV2.GetSPITFPBaudrateConfig(out enableDynamicBaudrate: boolean; out minimumDynamicBaudrate: longword)

Returns the baudrate config, see SetSPITFPBaudrateConfig.

New in version 2.0.10 (Firmware).

function TBrickIMUV2.GetSendTimeoutCount(const communicationMethod: byte): longword

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:

  • BRICK_IMU_V2_COMMUNICATION_METHOD_NONE = 0
  • BRICK_IMU_V2_COMMUNICATION_METHOD_USB = 1
  • BRICK_IMU_V2_COMMUNICATION_METHOD_SPI_STACK = 2
  • BRICK_IMU_V2_COMMUNICATION_METHOD_CHIBI = 3
  • BRICK_IMU_V2_COMMUNICATION_METHOD_RS485 = 4
  • BRICK_IMU_V2_COMMUNICATION_METHOD_WIFI = 5
  • BRICK_IMU_V2_COMMUNICATION_METHOD_ETHERNET = 6
  • BRICK_IMU_V2_COMMUNICATION_METHOD_WIFI_V2 = 7

New in version 2.0.7 (Firmware).

procedure TBrickIMUV2.SetSPITFPBaudrate(const brickletPort: char; const baudrate: longword)

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).

function TBrickIMUV2.GetSPITFPBaudrate(const brickletPort: char): longword

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

New in version 2.0.5 (Firmware).

procedure TBrickIMUV2.GetSPITFPErrorCount(const brickletPort: char; out errorCountACKChecksum: longword; out errorCountMessageChecksum: longword; out errorCountFrame: longword; out errorCountOverflow: longword)

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).

procedure TBrickIMUV2.EnableStatusLED

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.

procedure TBrickIMUV2.DisableStatusLED

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.

function TBrickIMUV2.IsStatusLEDEnabled: boolean

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

procedure TBrickIMUV2.GetProtocol1BrickletName(const port: char; out protocolVersion: byte; out firmwareVersion: array [0..2] of byte; out name: string)

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.

function TBrickIMUV2.GetChipTemperature: smallint

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.

procedure TBrickIMUV2.Reset

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!

procedure TBrickIMUV2.GetIdentity(out uid: string; out connectedUid: string; out position: char; out hardwareVersion: array [0..2] of byte; out firmwareVersion: array [0..2] of byte; out deviceIdentifier: word)

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

procedure TBrickIMUV2.SetAccelerationPeriod(const period: longword)

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

The default value is 0.

function TBrickIMUV2.GetAccelerationPeriod: longword

Returns the period as set by SetAccelerationPeriod.

procedure TBrickIMUV2.SetMagneticFieldPeriod(const period: longword)

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

function TBrickIMUV2.GetMagneticFieldPeriod: longword

Returns the period as set by SetMagneticFieldPeriod.

procedure TBrickIMUV2.SetAngularVelocityPeriod(const period: longword)

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

function TBrickIMUV2.GetAngularVelocityPeriod: longword

Returns the period as set by SetAngularVelocityPeriod.

procedure TBrickIMUV2.SetTemperaturePeriod(const period: longword)

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

function TBrickIMUV2.GetTemperaturePeriod: longword

Returns the period as set by SetTemperaturePeriod.

procedure TBrickIMUV2.SetOrientationPeriod(const period: longword)

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

function TBrickIMUV2.GetOrientationPeriod: longword

Returns the period as set by SetOrientationPeriod.

procedure TBrickIMUV2.SetLinearAccelerationPeriod(const period: longword)

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

function TBrickIMUV2.GetLinearAccelerationPeriod: longword

Returns the period as set by SetLinearAccelerationPeriod.

procedure TBrickIMUV2.SetGravityVectorPeriod(const period: longword)

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

function TBrickIMUV2.GetGravityVectorPeriod: longword

Returns the period as set by SetGravityVectorPeriod.

procedure TBrickIMUV2.SetQuaternionPeriod(const period: longword)

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

function TBrickIMUV2.GetQuaternionPeriod: longword

Returns the period as set by SetQuaternionPeriod.

procedure TBrickIMUV2.SetAllDataPeriod(const period: longword)

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

function TBrickIMUV2.GetAllDataPeriod: longword

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 by assigning a procedure to an callback property of the device object:

procedure TExample.MyCallback(sender: TBrickIMUV2; const param: word);
begin
  WriteLn(param);
end;

imuV2.OnExample := {$ifdef FPC}@{$endif}example.MyCallback;

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.

property TBrickIMUV2.OnAcceleration
procedure(sender: TBrickIMUV2; const x: smallint; const y: smallint; const z: smallint) of object;

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

property TBrickIMUV2.OnMagneticField
procedure(sender: TBrickIMUV2; const x: smallint; const y: smallint; const z: smallint) of object;

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

property TBrickIMUV2.OnAngularVelocity
procedure(sender: TBrickIMUV2; const x: smallint; const y: smallint; const z: smallint) of object;

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

property TBrickIMUV2.OnTemperature
procedure(sender: TBrickIMUV2; const temperature: shortint) of object;

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

property TBrickIMUV2.OnLinearAcceleration
procedure(sender: TBrickIMUV2; const x: smallint; const y: smallint; const z: smallint) of object;

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

property TBrickIMUV2.OnGravityVector
procedure(sender: TBrickIMUV2; const x: smallint; const y: smallint; const z: smallint) of object;

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

property TBrickIMUV2.OnOrientation
procedure(sender: TBrickIMUV2; const heading: smallint; const roll: smallint; const pitch: smallint) of object;

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

property TBrickIMUV2.OnQuaternion
procedure(sender: TBrickIMUV2; const w: smallint; const x: smallint; const y: smallint; const z: smallint) of object;

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

property TBrickIMUV2.OnAllData
procedure(sender: TBrickIMUV2; const acceleration: array [0..2] of smallint; const magneticField: array [0..2] of smallint; const angularVelocity: array [0..2] of smallint; const eulerAngle: array [0..2] of smallint; const quaternion: array [0..3] of smallint; const linearAcceleration: array [0..2] of smallint; const gravityVector: array [0..2] of smallint; const temperature: shortint; const calibrationStatus: byte) of object;

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

Constants

const BRICK_IMU_V2_DEVICE_IDENTIFIER

This constant is used to identify a IMU Brick 2.0.

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

const BRICK_IMU_V2_DEVICE_DISPLAY_NAME

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