Java - IMU Brick 2.0

This is the description of the Java 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 Java API bindings is part of their general description.

Examples

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

Simple

Download (ExampleSimple.java)

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
import com.tinkerforge.IPConnection;
import com.tinkerforge.BrickIMUV2;
import com.tinkerforge.BrickIMUV2.Quaternion;

public class ExampleSimple {
    private static final String HOST = "localhost";
    private static final int PORT = 4223;

    // Change XXYYZZ to the UID of your IMU Brick 2.0
    private static final String UID = "XXYYZZ";

    // Note: To make the example code cleaner we do not handle exceptions. Exceptions
    //       you might normally want to catch are described in the documentation
    public static void main(String args[]) throws Exception {
        IPConnection ipcon = new IPConnection(); // Create IP connection
        BrickIMUV2 imu = new BrickIMUV2(UID, ipcon); // Create device object

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

        // Get current quaternion
        Quaternion quaternion = imu.getQuaternion(); // Can throw com.tinkerforge.TimeoutException

        System.out.println("Quaternion [W]: " + quaternion.w/16383.0);
        System.out.println("Quaternion [X]: " + quaternion.x/16383.0);
        System.out.println("Quaternion [Y]: " + quaternion.y/16383.0);
        System.out.println("Quaternion [Z]: " + quaternion.z/16383.0);

        System.out.println("Press key to exit"); System.in.read();
        ipcon.disconnect();
    }
}

Callback

Download (ExampleCallback.java)

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
import com.tinkerforge.IPConnection;
import com.tinkerforge.BrickIMUV2;

public class ExampleCallback {
    private static final String HOST = "localhost";
    private static final int PORT = 4223;

    // Change XXYYZZ to the UID of your IMU Brick 2.0
    private static final String UID = "XXYYZZ";

    // Note: To make the example code cleaner we do not handle exceptions. Exceptions
    //       you might normally want to catch are described in the documentation
    public static void main(String args[]) throws Exception {
        IPConnection ipcon = new IPConnection(); // Create IP connection
        BrickIMUV2 imu = new BrickIMUV2(UID, ipcon); // Create device object

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

        // Add quaternion listener
        imu.addQuaternionListener(new BrickIMUV2.QuaternionListener() {
            public void quaternion(short w, short x, short y, short z) {
                System.out.println("Quaternion [W]: " + w/16383.0);
                System.out.println("Quaternion [X]: " + x/16383.0);
                System.out.println("Quaternion [Y]: " + y/16383.0);
                System.out.println("Quaternion [Z]: " + z/16383.0);
                System.out.println("");
            }
        });

        // Set period for quaternion callback to 0.1s (100ms)
        imu.setQuaternionPeriod(100);

        System.out.println("Press key to exit"); System.in.read();
        ipcon.disconnect();
    }
}

All Data

Download (ExampleAllData.java)

 1
 2
 3
 4
 5
 6
 7
 8
 9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
import com.tinkerforge.IPConnection;
import com.tinkerforge.BrickIMUV2;

public class ExampleAllData {
    private static final String HOST = "localhost";
    private static final int PORT = 4223;

    // Change XXYYZZ to the UID of your IMU Brick 2.0
    private static final String UID = "XXYYZZ";

    // Note: To make the example code cleaner we do not handle exceptions. Exceptions
    //       you might normally want to catch are described in the documentation
    public static void main(String args[]) throws Exception {
        IPConnection ipcon = new IPConnection(); // Create IP connection
        BrickIMUV2 imu = new BrickIMUV2(UID, ipcon); // Create device object

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

        // Add all data listener
        imu.addAllDataListener(new BrickIMUV2.AllDataListener() {
            public void allData(short[] acceleration, short[] magneticField,
                                short[] angularVelocity, short[] eulerAngle,
                                short[] quaternion, short[] linearAcceleration,
                                short[] gravityVector, byte temperature,
                                short calibrationStatus) {
                System.out.println("Acceleration [X]: " + acceleration[0]/100.0 + " m/s²");
                System.out.println("Acceleration [Y]: " + acceleration[1]/100.0 + " m/s²");
                System.out.println("Acceleration [Z]: " + acceleration[2]/100.0 + " m/s²");
                System.out.println("Magnetic Field [X]: " + magneticField[0]/16.0 + " µT");
                System.out.println("Magnetic Field [Y]: " + magneticField[1]/16.0 + " µT");
                System.out.println("Magnetic Field [Z]: " + magneticField[2]/16.0 + " µT");
                System.out.println("Angular Velocity [X]: " + angularVelocity[0]/16.0 + " °/s");
                System.out.println("Angular Velocity [Y]: " + angularVelocity[1]/16.0 + " °/s");
                System.out.println("Angular Velocity [Z]: " + angularVelocity[2]/16.0 + " °/s");
                System.out.println("Euler Angle [X]: " + eulerAngle[0]/16.0 + " °");
                System.out.println("Euler Angle [Y]: " + eulerAngle[1]/16.0 + " °");
                System.out.println("Euler Angle [Z]: " + eulerAngle[2]/16.0 + " °");
                System.out.println("Quaternion [W]: " + quaternion[0]/16383.0);
                System.out.println("Quaternion [X]: " + quaternion[1]/16383.0);
                System.out.println("Quaternion [Y]: " + quaternion[2]/16383.0);
                System.out.println("Quaternion [Z]: " + quaternion[3]/16383.0);
                System.out.println("Linear Acceleration [X]: " + linearAcceleration[0]/100.0 + " m/s²");
                System.out.println("Linear Acceleration [Y]: " + linearAcceleration[1]/100.0 + " m/s²");
                System.out.println("Linear Acceleration [Z]: " + linearAcceleration[2]/100.0 + " m/s²");
                System.out.println("Gravity Vector [X]: " + gravityVector[0]/100.0 + " m/s²");
                System.out.println("Gravity Vector [Y]: " + gravityVector[1]/100.0 + " m/s²");
                System.out.println("Gravity Vector [Z]: " + gravityVector[2]/100.0 + " m/s²");
                System.out.println("Temperature: " + temperature + " °C");
                System.out.println("Calibration Status: " + Integer.toBinaryString(calibrationStatus));
                System.out.println("");
            }
        });

        // Set period for all data callback to 0.1s (100ms)
        imu.setAllDataPeriod(100);

        System.out.println("Press key to exit"); System.in.read();
        ipcon.disconnect();
    }
}

API

Generally, every method of the Java bindings that returns a value can throw a TimeoutException. This exception gets thrown if the device did not respond. If a cable based connection is used, it is unlikely that this exception gets thrown (assuming nobody unplugs the device). However, if a wireless connection is used, timeouts will occur if the distance to the device gets too big.

Beside the TimeoutException there is also a NotConnectedException that is thrown if a method needs to communicate with the device while the IP Connection is not connected.

Since Java does not support multiple return values and return by reference is not possible for primitive types, we use small classes that only consist of member variables. The member variables of the returned objects are described in the corresponding method descriptions.

The package for all Brick/Bricklet bindings and the IP Connection is com.tinkerforge.*

All methods listed below are thread-safe.

Basic Functions

public class BrickIMUV2(String uid, IPConnection ipcon)

Creates an object with the unique device ID uid:

BrickIMUV2 imuV2 = new BrickIMUV2("YOUR_DEVICE_UID", ipcon);

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

public BrickIMUV2.Orientation getOrientation()

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 OrientationListener listener and set the period with setOrientationPeriod().

The returned object has the public member variables short heading, short roll and short pitch.

public BrickIMUV2.LinearAcceleration getLinearAcceleration()

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 LinearAccelerationListener listener and set the period with setLinearAccelerationPeriod().

The returned object has the public member variables short x, short y and short z.

public BrickIMUV2.GravityVector getGravityVector()

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 GravityVectorListener listener and set the period with setGravityVectorPeriod().

The returned object has the public member variables short x, short y and short z.

public BrickIMUV2.Quaternion getQuaternion()

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 QuaternionListener listener and set the period with setQuaternionPeriod().

The returned object has the public member variables short w, short x, short y and short z.

public BrickIMUV2.AllData getAllData()

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 AllDataListener listener and set the period with setAllDataPeriod().

The returned object has the public member variables short[] acceleration, short[] magneticField, short[] angularVelocity, short[] eulerAngle, short[] quaternion, short[] linearAcceleration, short[] gravityVector, byte temperature and short calibrationStatus.

public void ledsOn()

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

public void ledsOff()

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

public boolean areLedsOn()

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

Advanced Functions

public BrickIMUV2.Acceleration getAcceleration()

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 AccelerationListener listener and set the period with setAccelerationPeriod().

The returned object has the public member variables short x, short y and short z.

public BrickIMUV2.MagneticField getMagneticField()

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 MagneticFieldListener listener and set the period with setMagneticFieldPeriod().

The returned object has the public member variables short x, short y and short z.

public BrickIMUV2.AngularVelocity getAngularVelocity()

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 AngularVelocityListener alistener nd set the period with setAngularVelocityPeriod().

The returned object has the public member variables short x, short y and short z.

public byte getTemperature()

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

public boolean saveCalibration()

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.

public void setSensorConfiguration(short magnetometerRate, short gyroscopeRange, short gyroscopeBandwidth, short accelerometerRange, short accelerometerBandwidth)

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:

  • BrickIMUV2.MAGNETOMETER_RATE_2HZ = 0
  • BrickIMUV2.MAGNETOMETER_RATE_6HZ = 1
  • BrickIMUV2.MAGNETOMETER_RATE_8HZ = 2
  • BrickIMUV2.MAGNETOMETER_RATE_10HZ = 3
  • BrickIMUV2.MAGNETOMETER_RATE_15HZ = 4
  • BrickIMUV2.MAGNETOMETER_RATE_20HZ = 5
  • BrickIMUV2.MAGNETOMETER_RATE_25HZ = 6
  • BrickIMUV2.MAGNETOMETER_RATE_30HZ = 7
  • BrickIMUV2.GYROSCOPE_RANGE_2000DPS = 0
  • BrickIMUV2.GYROSCOPE_RANGE_1000DPS = 1
  • BrickIMUV2.GYROSCOPE_RANGE_500DPS = 2
  • BrickIMUV2.GYROSCOPE_RANGE_250DPS = 3
  • BrickIMUV2.GYROSCOPE_RANGE_125DPS = 4
  • BrickIMUV2.GYROSCOPE_BANDWIDTH_523HZ = 0
  • BrickIMUV2.GYROSCOPE_BANDWIDTH_230HZ = 1
  • BrickIMUV2.GYROSCOPE_BANDWIDTH_116HZ = 2
  • BrickIMUV2.GYROSCOPE_BANDWIDTH_47HZ = 3
  • BrickIMUV2.GYROSCOPE_BANDWIDTH_23HZ = 4
  • BrickIMUV2.GYROSCOPE_BANDWIDTH_12HZ = 5
  • BrickIMUV2.GYROSCOPE_BANDWIDTH_64HZ = 6
  • BrickIMUV2.GYROSCOPE_BANDWIDTH_32HZ = 7
  • BrickIMUV2.ACCELEROMETER_RANGE_2G = 0
  • BrickIMUV2.ACCELEROMETER_RANGE_4G = 1
  • BrickIMUV2.ACCELEROMETER_RANGE_8G = 2
  • BrickIMUV2.ACCELEROMETER_RANGE_16G = 3
  • BrickIMUV2.ACCELEROMETER_BANDWIDTH_7_81HZ = 0
  • BrickIMUV2.ACCELEROMETER_BANDWIDTH_15_63HZ = 1
  • BrickIMUV2.ACCELEROMETER_BANDWIDTH_31_25HZ = 2
  • BrickIMUV2.ACCELEROMETER_BANDWIDTH_62_5HZ = 3
  • BrickIMUV2.ACCELEROMETER_BANDWIDTH_125HZ = 4
  • BrickIMUV2.ACCELEROMETER_BANDWIDTH_250HZ = 5
  • BrickIMUV2.ACCELEROMETER_BANDWIDTH_500HZ = 6
  • BrickIMUV2.ACCELEROMETER_BANDWIDTH_1000HZ = 7

New in version 2.0.5 (Firmware).

public BrickIMUV2.SensorConfiguration getSensorConfiguration()

Returns the sensor configuration as set by setSensorConfiguration().

The following constants are available for this function:

  • BrickIMUV2.MAGNETOMETER_RATE_2HZ = 0
  • BrickIMUV2.MAGNETOMETER_RATE_6HZ = 1
  • BrickIMUV2.MAGNETOMETER_RATE_8HZ = 2
  • BrickIMUV2.MAGNETOMETER_RATE_10HZ = 3
  • BrickIMUV2.MAGNETOMETER_RATE_15HZ = 4
  • BrickIMUV2.MAGNETOMETER_RATE_20HZ = 5
  • BrickIMUV2.MAGNETOMETER_RATE_25HZ = 6
  • BrickIMUV2.MAGNETOMETER_RATE_30HZ = 7
  • BrickIMUV2.GYROSCOPE_RANGE_2000DPS = 0
  • BrickIMUV2.GYROSCOPE_RANGE_1000DPS = 1
  • BrickIMUV2.GYROSCOPE_RANGE_500DPS = 2
  • BrickIMUV2.GYROSCOPE_RANGE_250DPS = 3
  • BrickIMUV2.GYROSCOPE_RANGE_125DPS = 4
  • BrickIMUV2.GYROSCOPE_BANDWIDTH_523HZ = 0
  • BrickIMUV2.GYROSCOPE_BANDWIDTH_230HZ = 1
  • BrickIMUV2.GYROSCOPE_BANDWIDTH_116HZ = 2
  • BrickIMUV2.GYROSCOPE_BANDWIDTH_47HZ = 3
  • BrickIMUV2.GYROSCOPE_BANDWIDTH_23HZ = 4
  • BrickIMUV2.GYROSCOPE_BANDWIDTH_12HZ = 5
  • BrickIMUV2.GYROSCOPE_BANDWIDTH_64HZ = 6
  • BrickIMUV2.GYROSCOPE_BANDWIDTH_32HZ = 7
  • BrickIMUV2.ACCELEROMETER_RANGE_2G = 0
  • BrickIMUV2.ACCELEROMETER_RANGE_4G = 1
  • BrickIMUV2.ACCELEROMETER_RANGE_8G = 2
  • BrickIMUV2.ACCELEROMETER_RANGE_16G = 3
  • BrickIMUV2.ACCELEROMETER_BANDWIDTH_7_81HZ = 0
  • BrickIMUV2.ACCELEROMETER_BANDWIDTH_15_63HZ = 1
  • BrickIMUV2.ACCELEROMETER_BANDWIDTH_31_25HZ = 2
  • BrickIMUV2.ACCELEROMETER_BANDWIDTH_62_5HZ = 3
  • BrickIMUV2.ACCELEROMETER_BANDWIDTH_125HZ = 4
  • BrickIMUV2.ACCELEROMETER_BANDWIDTH_250HZ = 5
  • BrickIMUV2.ACCELEROMETER_BANDWIDTH_500HZ = 6
  • BrickIMUV2.ACCELEROMETER_BANDWIDTH_1000HZ = 7

New in version 2.0.5 (Firmware).

The returned object has the public member variables short magnetometerRate, short gyroscopeRange, short gyroscopeBandwidth, short accelerometerRange and short accelerometerBandwidth.

public void setSensorFusionMode(short mode)

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:

  • BrickIMUV2.SENSOR_FUSION_OFF = 0
  • BrickIMUV2.SENSOR_FUSION_ON = 1
  • BrickIMUV2.SENSOR_FUSION_ON_WITHOUT_MAGNETOMETER = 2
  • BrickIMUV2.SENSOR_FUSION_ON_WITHOUT_FAST_MAGNETOMETER_CALIBRATION = 3

New in version 2.0.5 (Firmware).

public short getSensorFusionMode()

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

The following constants are available for this function:

  • BrickIMUV2.SENSOR_FUSION_OFF = 0
  • BrickIMUV2.SENSOR_FUSION_ON = 1
  • BrickIMUV2.SENSOR_FUSION_ON_WITHOUT_MAGNETOMETER = 2
  • BrickIMUV2.SENSOR_FUSION_ON_WITHOUT_FAST_MAGNETOMETER_CALIBRATION = 3

New in version 2.0.5 (Firmware).

public short[] getAPIVersion()

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.

public boolean getResponseExpected(short functionId)

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 listener 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.

public void setResponseExpected(short functionId, boolean responseExpected)

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 listener 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:

  • BrickIMUV2.FUNCTION_LEDS_ON = 10
  • BrickIMUV2.FUNCTION_LEDS_OFF = 11
  • BrickIMUV2.FUNCTION_SET_ACCELERATION_PERIOD = 14
  • BrickIMUV2.FUNCTION_SET_MAGNETIC_FIELD_PERIOD = 16
  • BrickIMUV2.FUNCTION_SET_ANGULAR_VELOCITY_PERIOD = 18
  • BrickIMUV2.FUNCTION_SET_TEMPERATURE_PERIOD = 20
  • BrickIMUV2.FUNCTION_SET_ORIENTATION_PERIOD = 22
  • BrickIMUV2.FUNCTION_SET_LINEAR_ACCELERATION_PERIOD = 24
  • BrickIMUV2.FUNCTION_SET_GRAVITY_VECTOR_PERIOD = 26
  • BrickIMUV2.FUNCTION_SET_QUATERNION_PERIOD = 28
  • BrickIMUV2.FUNCTION_SET_ALL_DATA_PERIOD = 30
  • BrickIMUV2.FUNCTION_SET_SENSOR_CONFIGURATION = 41
  • BrickIMUV2.FUNCTION_SET_SENSOR_FUSION_MODE = 43
  • BrickIMUV2.FUNCTION_SET_SPITFP_BAUDRATE_CONFIG = 231
  • BrickIMUV2.FUNCTION_SET_SPITFP_BAUDRATE = 234
  • BrickIMUV2.FUNCTION_ENABLE_STATUS_LED = 238
  • BrickIMUV2.FUNCTION_DISABLE_STATUS_LED = 239
  • BrickIMUV2.FUNCTION_RESET = 243
public void setResponseExpectedAll(boolean responseExpected)

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

public void setSPITFPBaudrateConfig(boolean enableDynamicBaudrate, long minimumDynamicBaudrate)

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).

public BrickIMUV2.SPITFPBaudrateConfig getSPITFPBaudrateConfig()

Returns the baudrate config, see setSPITFPBaudrateConfig().

New in version 2.0.10 (Firmware).

The returned object has the public member variables boolean enableDynamicBaudrate and long minimumDynamicBaudrate.

public long getSendTimeoutCount(short communicationMethod)

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:

  • BrickIMUV2.COMMUNICATION_METHOD_NONE = 0
  • BrickIMUV2.COMMUNICATION_METHOD_USB = 1
  • BrickIMUV2.COMMUNICATION_METHOD_SPI_STACK = 2
  • BrickIMUV2.COMMUNICATION_METHOD_CHIBI = 3
  • BrickIMUV2.COMMUNICATION_METHOD_RS485 = 4
  • BrickIMUV2.COMMUNICATION_METHOD_WIFI = 5
  • BrickIMUV2.COMMUNICATION_METHOD_ETHERNET = 6
  • BrickIMUV2.COMMUNICATION_METHOD_WIFI_V2 = 7

New in version 2.0.7 (Firmware).

public void setSPITFPBaudrate(char brickletPort, long baudrate)

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).

public long getSPITFPBaudrate(char brickletPort)

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

New in version 2.0.5 (Firmware).

public BrickIMUV2.SPITFPErrorCount getSPITFPErrorCount(char brickletPort)

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).

The returned object has the public member variables long errorCountACKChecksum, long errorCountMessageChecksum, long errorCountFrame and long errorCountOverflow.

public void 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.

public void 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.

public boolean isStatusLEDEnabled()

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

public BrickIMUV2.Protocol1BrickletName getProtocol1BrickletName(char port)

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.

The returned object has the public member variables short protocolVersion, short[] firmwareVersion and String name.

public short getChipTemperature()

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.

public void 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!

public BrickIMUV2.Identity getIdentity()

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.

The returned object has the public member variables String uid, String connectedUid, char position, short[] hardwareVersion, short[] firmwareVersion and int deviceIdentifier.

Listener Configuration Functions

public void setAccelerationPeriod(long period)

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

The default value is 0.

public long getAccelerationPeriod()

Returns the period as set by setAccelerationPeriod().

public void setMagneticFieldPeriod(long period)

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

public long getMagneticFieldPeriod()

Returns the period as set by setMagneticFieldPeriod().

public void setAngularVelocityPeriod(long period)

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

public long getAngularVelocityPeriod()

Returns the period as set by setAngularVelocityPeriod().

public void setTemperaturePeriod(long period)

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

public long getTemperaturePeriod()

Returns the period as set by setTemperaturePeriod().

public void setOrientationPeriod(long period)

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

public long getOrientationPeriod()

Returns the period as set by setOrientationPeriod().

public void setLinearAccelerationPeriod(long period)

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

public long getLinearAccelerationPeriod()

Returns the period as set by setLinearAccelerationPeriod().

public void setGravityVectorPeriod(long period)

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

public long getGravityVectorPeriod()

Returns the period as set by setGravityVectorPeriod().

public void setQuaternionPeriod(long period)

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

public long getQuaternionPeriod()

Returns the period as set by setQuaternionPeriod().

public void setAllDataPeriod(long period)

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

public long getAllDataPeriod()

Returns the period as set by setAllDataPeriod().

Listeners

Listeners can be registered to receive time critical or recurring data from the device. The registration is done with "add*Listener" functions of the device object.

The parameter is a listener class object, for example:

device.addExampleListener(new BrickIMUV2.ExampleListener() {
    public void property(int value) {
        System.out.println("Value: " + value);
    }
});

The available listener classes with inherent methods to be overwritten are described below. It is possible to add several listeners and to remove them with the corresponding "remove*Listener" function.

Note

Using listeners 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.

public class BrickIMUV2.AccelerationListener()

This listener can be added with the addAccelerationListener() function. An added listener can be removed with the removeAccelerationListener() function.

public void acceleration(short x, short y, short z)

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

public class BrickIMUV2.MagneticFieldListener()

This listener can be added with the addMagneticFieldListener() function. An added listener can be removed with the removeMagneticFieldListener() function.

public void magneticField(short x, short y, short z)

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

public class BrickIMUV2.AngularVelocityListener()

This listener can be added with the addAngularVelocityListener() function. An added listener can be removed with the removeAngularVelocityListener() function.

public void angularVelocity(short x, short y, short z)

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

public class BrickIMUV2.TemperatureListener()

This listener can be added with the addTemperatureListener() function. An added listener can be removed with the removeTemperatureListener() function.

public void temperature(byte temperature)

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

public class BrickIMUV2.LinearAccelerationListener()

This listener can be added with the addLinearAccelerationListener() function. An added listener can be removed with the removeLinearAccelerationListener() function.

public void linearAcceleration(short x, short y, short z)

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

public class BrickIMUV2.GravityVectorListener()

This listener can be added with the addGravityVectorListener() function. An added listener can be removed with the removeGravityVectorListener() function.

public void gravityVector(short x, short y, short z)

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

public class BrickIMUV2.OrientationListener()

This listener can be added with the addOrientationListener() function. An added listener can be removed with the removeOrientationListener() function.

public void orientation(short heading, short roll, short pitch)

This listener 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.

public class BrickIMUV2.QuaternionListener()

This listener can be added with the addQuaternionListener() function. An added listener can be removed with the removeQuaternionListener() function.

public void quaternion(short w, short x, short y, short z)

This listener 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.

public class BrickIMUV2.AllDataListener()

This listener can be added with the addAllDataListener() function. An added listener can be removed with the removeAllDataListener() function.

public void allData(short[] acceleration, short[] magneticField, short[] angularVelocity, short[] eulerAngle, short[] quaternion, short[] linearAcceleration, short[] gravityVector, byte temperature, short calibrationStatus)

This listener is triggered periodically with the period that is set by setAllDataPeriod(). The parameters are as for getAllData().

Constants

public static final int BrickIMUV2.DEVICE_IDENTIFIER

This constant is used to identify a IMU Brick 2.0.

The getIdentity() function and the EnumerateListener listener of the IP Connection have a deviceIdentifier parameter to specify the Brick's or Bricklet's type.

public static final String BrickIMUV2.DEVICE_DISPLAY_NAME

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