Specifications / TCP/IP Protocol / API / Bricks and Bricklets / Bricks (Discontinued) / IMU Brick

TCP/IP - IMU Brick¶

This is the description of the TCP/IP protocol for the IMU Brick. General information and technical specifications for the IMU Brick are summarized in its hardware description.

API¶

A general description of the TCP/IP protocol structure can be found here.

Basic Functions¶

BrickIMU.get_orientation¶

Function ID:	5
Request:	empty payload
Response:	roll – Type: int16, Unit: 1/100 °, Range: [-18000 to 18000] pitch – Type: int16, Unit: 1/100 °, Range: [-18000 to 18000] yaw – Type: int16, Unit: 1/100 °, Range: [-18000 to 18000]

Returns the current orientation (roll, pitch, yaw) of the IMU Brick as Euler angles. Note that Euler angles always experience a gimbal lock.

We recommend that you use quaternions instead.

The order to sequence in which the orientation values should be applied is roll, yaw, pitch.

If you want to get the orientation periodically, it is recommended to use the CALLBACK_ORIENTATION callback and set the period with set_orientation_period.

BrickIMU.get_quaternion¶

Function ID:	6
Request:	empty payload
Response:	x – Type: float, Range: [-1.0 to 1.0] y – Type: float, Range: [-1.0 to 1.0] z – Type: float, Range: [-1.0 to 1.0] w – Type: float, Range: [-1.0 to 1.0]

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

You can go from quaternions to Euler angles with the following formula:

xAngle = atan2(2*y*w - 2*x*z, 1 - 2*y*y - 2*z*z)
yAngle = atan2(2*x*w - 2*y*z, 1 - 2*x*x - 2*z*z)
zAngle =  asin(2*x*y + 2*z*w)

This process is not reversible, because of the gimbal lock.

It is also possible to calculate independent angles. You can calculate yaw, pitch and roll in a right-handed vehicle coordinate system according to DIN70000 with:

yaw   =  atan2(2*x*y + 2*w*z, w*w + x*x - y*y - z*z)
pitch = -asin(2*w*y - 2*x*z)
roll  = -atan2(2*y*z + 2*w*x, -w*w + x*x + y*y - z*z))

Converting the quaternions to an OpenGL transformation matrix is possible with the following formula:

matrix = [[1 - 2*(y*y + z*z),     2*(x*y - w*z),     2*(x*z + w*y), 0],
          [    2*(x*y + w*z), 1 - 2*(x*x + z*z),     2*(y*z - w*x), 0],
          [    2*(x*z - w*y),     2*(y*z + w*x), 1 - 2*(x*x + y*y), 0],
          [                0,                 0,                 0, 1]]

If you want to get the quaternions periodically, it is recommended to use the CALLBACK_QUATERNION callback and set the period with set_quaternion_period.

BrickIMU.leds_on¶

Function ID:	8
Request:	empty payload
Response:	no response

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

BrickIMU.leds_off¶

Function ID:	9
Request:	empty payload
Response:	no response

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

BrickIMU.are_leds_on¶

Function ID:	10
Request:	empty payload
Response:	leds – Type: bool, Default: true

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

BrickIMU.set_convergence_speed¶

Function ID:	15
Request:	speed – Type: uint16, Unit: 1 °/s, Range: [0 to 2¹⁶ - 1], Default: 30
Response:	no response

Sets the convergence speed of the IMU Brick. The convergence speed determines how the different sensor measurements are fused.

If the orientation of the IMU Brick is off by 10° and the convergence speed is set to 20°/s, it will take 0.5s until the orientation is corrected. However, if the correct orientation is reached and the convergence speed is too high, the orientation will fluctuate with the fluctuations of the accelerometer and the magnetometer.

If you set the convergence speed to 0, practically only the gyroscope is used to calculate the orientation. This gives very smooth movements, but errors of the gyroscope will not be corrected. If you set the convergence speed to something above 500, practically only the magnetometer and the accelerometer are used to calculate the orientation. In this case the movements are abrupt and the values will fluctuate, but there won't be any errors that accumulate over time.

In an application with high angular velocities, we recommend a high convergence speed, so the errors of the gyroscope can be corrected fast. In applications with only slow movements we recommend a low convergence speed. You can change the convergence speed on the fly. So it is possible (and recommended) to increase the convergence speed before an abrupt movement and decrease it afterwards again.

You might want to play around with the convergence speed in the Brick Viewer to get a feeling for a good value for your application.

BrickIMU.get_convergence_speed¶

Function ID:	16
Request:	empty payload
Response:	speed – Type: uint16, Unit: 1 °/s, Range: [0 to 2¹⁶ - 1], Default: 30

Returns the convergence speed as set by set_convergence_speed.

Advanced Functions¶

BrickIMU.get_acceleration¶

Function ID:	1
Request:	empty payload
Response:	x – Type: int16, Unit: 1/1000 gₙ, Range: [-2¹⁵ to 2¹⁵ - 1] y – Type: int16, Unit: 1/1000 gₙ, Range: [-2¹⁵ to 2¹⁵ - 1] z – Type: int16, Unit: 1/1000 gₙ, Range: [-2¹⁵ to 2¹⁵ - 1]

Returns the calibrated acceleration from the accelerometer for the x, y and z axis.

If you want to get the acceleration periodically, it is recommended to use the CALLBACK_ACCELERATION callback and set the period with set_acceleration_period.

BrickIMU.get_magnetic_field¶

Function ID:	2
Request:	empty payload
Response:	x – Type: int16, Unit: 1/10 µT, Range: [-2¹⁵ to 2¹⁵ - 1] y – Type: int16, Unit: 1/10 µT, Range: [-2¹⁵ to 2¹⁵ - 1] z – Type: int16, Unit: 1/10 µT, Range: [-2¹⁵ to 2¹⁵ - 1]

Returns the calibrated magnetic field from the magnetometer for the x, y and z axis.

If you want to get the magnetic field periodically, it is recommended to use the CALLBACK_MAGNETIC_FIELD callback and set the period with set_magnetic_field_period.

BrickIMU.get_angular_velocity¶

Function ID:	3
Request:	empty payload
Response:	x – Type: int16, Unit: 8/115 °/s, Range: [-28750 to 28750] y – Type: int16, Unit: 8/115 °/s, Range: [-28750 to 28750] z – Type: int16, Unit: 8/115 °/s, Range: [-28750 to 28750]

Returns the calibrated angular velocity from the gyroscope for the x, y and z axis in °/14.375s (you have to divide by 14.375 to get the value in °/s).

If you want to get the angular velocity periodically, it is recommended to use the CALLBACK_ANGULAR_VELOCITY callback and set the period with set_angular_velocity_period.

BrickIMU.get_all_data¶

Function ID:	4
Request:	empty payload
Response:	acc_x – Type: int16, Unit: 1/1000 gₙ, Range: [-2¹⁵ to 2¹⁵ - 1] acc_y – Type: int16, Unit: 1/1000 gₙ, Range: [-2¹⁵ to 2¹⁵ - 1] acc_z – Type: int16, Unit: 1/1000 gₙ, Range: [-2¹⁵ to 2¹⁵ - 1] mag_x – Type: int16, Unit: 1/10 µT, Range: [-2¹⁵ to 2¹⁵ - 1] mag_y – Type: int16, Unit: 1/10 µT, Range: [-2¹⁵ to 2¹⁵ - 1] mag_z – Type: int16, Unit: 1/10 µT, Range: [-2¹⁵ to 2¹⁵ - 1] ang_x – Type: int16, Unit: 8/115 °/s, Range: [-28750 to 28750] ang_y – Type: int16, Unit: 8/115 °/s, Range: [-28750 to 28750] ang_z – Type: int16, Unit: 8/115 °/s, Range: [-28750 to 28750] temperature – Type: int16, Unit: 1/100 °C, Range: [-2¹⁵ to 2¹⁵ - 1]

Returns the data from get_acceleration, get_magnetic_field and get_angular_velocity as well as the temperature of the IMU Brick.

If you want to get the data periodically, it is recommended to use the CALLBACK_ALL_DATA callback and set the period with set_all_data_period.

BrickIMU.get_imu_temperature¶

Function ID:	7
Request:	empty payload
Response:	temperature – Type: int16, Unit: 1/100 °C, Range: [-2¹⁵ to 2¹⁵ - 1]

Returns the temperature of the IMU Brick.

BrickIMU.set_acceleration_range¶

Function ID:	11
Request:	range – Type: uint8, Range: [0 to 255]
Response:	no response

Not implemented yet.

BrickIMU.get_acceleration_range¶

Function ID:	12
Request:	empty payload
Response:	range – Type: uint8, Range: [0 to 255]

Not implemented yet.

BrickIMU.set_magnetometer_range¶

Function ID:	13
Request:	range – Type: uint8, Range: [0 to 255]
Response:	no response

Not implemented yet.

BrickIMU.get_magnetometer_range¶

Function ID:	14
Request:	empty payload
Response:	range – Type: uint8, Range: [0 to 255]

Not implemented yet.

BrickIMU.set_calibration¶

Function ID:	17
Request:	typ – Type: uint8, Range: See meanings data – Type: int16[10], Range: [-2¹⁵ to 2¹⁵ - 1]
Response:	no response

There are several different types that can be calibrated:

Type	Description	Values
0	Accelerometer Gain	`[mul x, mul y, mul z, div x, div y, div z, 0, 0, 0, 0]`
1	Accelerometer Bias	`[bias x, bias y, bias z, 0, 0, 0, 0, 0, 0, 0]`
2	Magnetometer Gain	`[mul x, mul y, mul z, div x, div y, div z, 0, 0, 0, 0]`
3	Magnetometer Bias	`[bias x, bias y, bias z, 0, 0, 0, 0, 0, 0, 0]`
4	Gyroscope Gain	`[mul x, mul y, mul z, div x, div y, div z, 0, 0, 0, 0]`
5	Gyroscope Bias	`[bias xl, bias yl, bias zl, temp l, bias xh, bias yh, bias zh, temp h, 0, 0]`

The calibration via gain and bias is done with the following formula:

new_value = (bias + orig_value) * gain_mul / gain_div

If you really want to write your own calibration software, please keep in mind that you first have to undo the old calibration (set bias to 0 and gain to 1/1) and that you have to average over several thousand values to obtain a usable result in the end.

The gyroscope bias is highly dependent on the temperature, so you have to calibrate the bias two times with different temperatures. The values xl, yl, zl and temp l are the bias for x, y, z and the corresponding temperature for a low temperature. The values xh, yh, zh and temp h are the same for a high temperatures. The temperature difference should be at least 5°C. If you have a temperature where the IMU Brick is mostly used, you should use this temperature for one of the sampling points.

Note

We highly recommend that you use the Brick Viewer to calibrate your IMU Brick.

The following meanings are defined for the elements of this function:

For typ:

0 = Accelerometer Gain
1 = Accelerometer Bias
2 = Magnetometer Gain
3 = Magnetometer Bias
4 = Gyroscope Gain
5 = Gyroscope Bias

BrickIMU.get_calibration¶

Function ID:	18
Request:	typ – Type: uint8, Range: See meanings
Response:	data – Type: int16[10], Range: [-2¹⁵ to 2¹⁵ - 1]

Returns the calibration for a given type as set by set_calibration.

The following meanings are defined for the elements of this function:

For typ:

0 = Accelerometer Gain
1 = Accelerometer Bias
2 = Magnetometer Gain
3 = Magnetometer Bias
4 = Gyroscope Gain
5 = Gyroscope Bias

BrickIMU.orientation_calculation_on¶

Function ID:	37
Request:	empty payload
Response:	no response

Turns the orientation calculation of the IMU Brick on.

As default the calculation is on.

New in version 2.0.2 (Firmware).

BrickIMU.orientation_calculation_off¶

Function ID:	38
Request:	empty payload
Response:	no response

Turns the orientation calculation of the IMU Brick off.

If the calculation is off, get_orientation will return the last calculated value until the calculation is turned on again.

The trigonometric functions that are needed to calculate the orientation are very expensive. We recommend to turn the orientation calculation off if the orientation is not needed, to free calculation time for the sensor fusion algorithm.

As default the calculation is on.

New in version 2.0.2 (Firmware).

BrickIMU.is_orientation_calculation_on¶

Function ID:	39
Request:	empty payload
Response:	orientation_calculation_on – Type: bool, Default: true

Returns true if the orientation calculation of the IMU Brick is on, false otherwise.

New in version 2.0.2 (Firmware).

BrickIMU.set_spitfp_baudrate_config¶

Function ID:	231
Request:	enable_dynamic_baudrate – Type: bool, Default: true minimum_dynamic_baudrate – Type: uint32, Unit: 1 Bd, Range: [400000 to 2000000], Default: 400000
Response:	no response

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 sent/received and decreased linearly if little data is sent/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 set_spitfp_baudrate. If the dynamic baudrate is disabled, the baudrate as set by set_spitfp_baudrate will be used statically.

New in version 2.3.5 (Firmware).

BrickIMU.get_spitfp_baudrate_config¶

Function ID:	232
Request:	empty payload
Response:	enable_dynamic_baudrate – Type: bool, Default: true minimum_dynamic_baudrate – Type: uint32, Unit: 1 Bd, Range: [400000 to 2000000], Default: 400000

Returns the baudrate config, see set_spitfp_baudrate_config.

New in version 2.3.5 (Firmware).

BrickIMU.get_send_timeout_count¶

Function ID:	233
Request:	communication_method – Type: uint8, Range: See meanings
Response:	timeout_count – Type: uint32, Range: [0 to 2³² - 1]

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 meanings are defined for the elements of this function:

For communication_method:

0 = None
1 = USB
2 = SPI Stack
3 = Chibi
4 = RS485
5 = WIFI
6 = Ethernet
7 = WIFI V2

New in version 2.3.3 (Firmware).

BrickIMU.set_spitfp_baudrate¶

Function ID:	234
Request:	bricklet_port – Type: char, Range: ['a' to 'b'] baudrate – Type: uint32, Unit: 1 Bd, Range: [400000 to 2000000], Default: 1400000
Response:	no response

Sets the baudrate for a specific Bricklet port.

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 get_spitfp_error_count) you can decrease the baudrate.

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

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

New in version 2.3.3 (Firmware).

BrickIMU.get_spitfp_baudrate¶

Function ID:	235
Request:	bricklet_port – Type: char, Range: ['a' to 'b']
Response:	baudrate – Type: uint32, Unit: 1 Bd, Range: [400000 to 2000000], Default: 1400000

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

New in version 2.3.3 (Firmware).

BrickIMU.get_spitfp_error_count¶

Function ID:	237
Request:	bricklet_port – Type: char, Range: ['a' to 'b']
Response:	error_count_ack_checksum – Type: uint32, Range: [0 to 2³² - 1] error_count_message_checksum – Type: uint32, Range: [0 to 2³² - 1] error_count_frame – Type: uint32, Range: [0 to 2³² - 1] error_count_overflow – Type: uint32, Range: [0 to 2³² - 1]

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 2.3.3 (Firmware).

BrickIMU.enable_status_led¶

Function ID:	238
Request:	empty payload
Response:	no response

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.

New in version 2.3.1 (Firmware).

BrickIMU.disable_status_led¶

Function ID:	239
Request:	empty payload
Response:	no response

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.

New in version 2.3.1 (Firmware).

BrickIMU.is_status_led_enabled¶

Function ID:	240
Request:	empty payload
Response:	enabled – Type: bool, Default: true

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

New in version 2.3.1 (Firmware).

BrickIMU.get_chip_temperature¶

Function ID:	242
Request:	empty payload
Response:	temperature – Type: int16, Unit: 1/10 °C, Range: [-2¹⁵ to 2¹⁵ - 1]

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

The temperature is only proportional to the real temperature and it has an accuracy of ±15%. Practically it is only useful as an indicator for temperature changes.

BrickIMU.reset¶

Function ID:	243
Request:	empty payload
Response:	no response

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!

BrickIMU.get_identity¶

Function ID:	255
Request:	empty payload
Response:	uid – Type: char[8] connected_uid – Type: char[8] position – Type: char, Range: ['0' to '8'] hardware_version – Type: uint8[3] 0: major – Type: uint8, Range: [0 to 255] 1: minor – Type: uint8, Range: [0 to 255] 2: revision – Type: uint8, Range: [0 to 255] firmware_version – Type: uint8[3] 0: major – Type: uint8, Range: [0 to 255] 1: minor – Type: uint8, Range: [0 to 255] 2: revision – Type: uint8, Range: [0 to 255] device_identifier – Type: uint16, Range: [0 to 2¹⁶ - 1]

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 is the position in the stack from '0' (bottom) to '8' (top).

The device identifier numbers can be found here.

Callback Configuration Functions¶

BrickIMU.set_acceleration_period¶

Function ID:	19
Request:	period – Type: uint32, Unit: 1 ms, Range: [0 to 2³² - 1], Default: 0
Response:	no response

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

BrickIMU.get_acceleration_period¶

Function ID:	20
Request:	empty payload
Response:	period – Type: uint32, Unit: 1 ms, Range: [0 to 2³² - 1], Default: 0

Returns the period as set by set_acceleration_period.

BrickIMU.set_magnetic_field_period¶

Function ID:	21
Request:	period – Type: uint32, Unit: 1 ms, Range: [0 to 2³² - 1], Default: 0
Response:	no response

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

BrickIMU.get_magnetic_field_period¶

Function ID:	22
Request:	empty payload
Response:	period – Type: uint32, Unit: 1 ms, Range: [0 to 2³² - 1], Default: 0

Returns the period as set by set_magnetic_field_period.

BrickIMU.set_angular_velocity_period¶

Function ID:	23
Request:	period – Type: uint32, Unit: 1 ms, Range: [0 to 2³² - 1], Default: 0
Response:	no response

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

BrickIMU.get_angular_velocity_period¶

Function ID:	24
Request:	empty payload
Response:	period – Type: uint32, Unit: 1 ms, Range: [0 to 2³² - 1], Default: 0

Returns the period as set by set_angular_velocity_period.

BrickIMU.set_all_data_period¶

Function ID:	25
Request:	period – Type: uint32, Unit: 1 ms, Range: [0 to 2³² - 1], Default: 0
Response:	no response

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

BrickIMU.get_all_data_period¶

Function ID:	26
Request:	empty payload
Response:	period – Type: uint32, Unit: 1 ms, Range: [0 to 2³² - 1], Default: 0

Returns the period as set by set_all_data_period.

BrickIMU.set_orientation_period¶

Function ID:	27
Request:	period – Type: uint32, Unit: 1 ms, Range: [0 to 2³² - 1], Default: 0
Response:	no response

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

BrickIMU.get_orientation_period¶

Function ID:	28
Request:	empty payload
Response:	period – Type: uint32, Unit: 1 ms, Range: [0 to 2³² - 1], Default: 0

Returns the period as set by set_orientation_period.

BrickIMU.set_quaternion_period¶

Function ID:	29
Request:	period – Type: uint32, Unit: 1 ms, Range: [0 to 2³² - 1], Default: 0
Response:	no response

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

BrickIMU.get_quaternion_period¶

Function ID:	30
Request:	empty payload
Response:	period – Type: uint32, Unit: 1 ms, Range: [0 to 2³² - 1], Default: 0

Returns the period as set by set_quaternion_period.

Callbacks¶

BrickIMU.CALLBACK_ACCELERATION¶

Function ID:	31
Response:	x – Type: int16, Unit: 1/1000 gₙ, Range: [-2¹⁵ to 2¹⁵ - 1] y – Type: int16, Unit: 1/1000 gₙ, Range: [-2¹⁵ to 2¹⁵ - 1] z – Type: int16, Unit: 1/1000 gₙ, Range: [-2¹⁵ to 2¹⁵ - 1]

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

BrickIMU.CALLBACK_MAGNETIC_FIELD¶

Function ID:	32
Response:	x – Type: int16, Unit: 1/10 µT, Range: [-2¹⁵ to 2¹⁵ - 1] y – Type: int16, Unit: 1/10 µT, Range: [-2¹⁵ to 2¹⁵ - 1] z – Type: int16, Unit: 1/10 µT, Range: [-2¹⁵ to 2¹⁵ - 1]

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

BrickIMU.CALLBACK_ANGULAR_VELOCITY¶

Function ID:	33
Response:	x – Type: int16, Unit: 8/115 °/s, Range: [-28750 to 28750] y – Type: int16, Unit: 8/115 °/s, Range: [-28750 to 28750] z – Type: int16, Unit: 8/115 °/s, Range: [-28750 to 28750]

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

BrickIMU.CALLBACK_ALL_DATA¶

Function ID:

Function ID:	34
Response:	acc_x – Type: int16, Unit: 1/1000 gₙ, Range: [-2¹⁵ to 2¹⁵ - 1] acc_y – Type: int16, Unit: 1/1000 gₙ, Range: [-2¹⁵ to 2¹⁵ - 1] acc_z – Type: int16, Unit: 1/1000 gₙ, Range: [-2¹⁵ to 2¹⁵ - 1] mag_x – Type: int16, Unit: 1/10 µT, Range: [-2¹⁵ to 2¹⁵ - 1] mag_y – Type: int16, Unit: 1/10 µT, Range: [-2¹⁵ to 2¹⁵ - 1] mag_z – Type: int16, Unit: 1/10 µT, Range: [-2¹⁵ to 2¹⁵ - 1] ang_x – Type: int16, Unit: 8/115 °/s, Range: [-28750 to 28750] ang_y – Type: int16, Unit: 8/115 °/s, Range: [-28750 to 28750] ang_z – Type: int16, Unit: 8/115 °/s, Range: [-28750 to 28750] temperature – Type: int16, Unit: 1/100 °C, Range: [-2¹⁵ to 2¹⁵ - 1]

Response:

acc_x – Type: int16, Unit: 1/1000 gₙ, Range: [-2¹⁵ to 2¹⁵ - 1]
acc_y – Type: int16, Unit: 1/1000 gₙ, Range: [-2¹⁵ to 2¹⁵ - 1]
acc_z – Type: int16, Unit: 1/1000 gₙ, Range: [-2¹⁵ to 2¹⁵ - 1]
mag_x – Type: int16, Unit: 1/10 µT, Range: [-2¹⁵ to 2¹⁵ - 1]
mag_y – Type: int16, Unit: 1/10 µT, Range: [-2¹⁵ to 2¹⁵ - 1]
mag_z – Type: int16, Unit: 1/10 µT, Range: [-2¹⁵ to 2¹⁵ - 1]
ang_x – Type: int16, Unit: 8/115 °/s, Range: [-28750 to 28750]
ang_y – Type: int16, Unit: 8/115 °/s, Range: [-28750 to 28750]
ang_z – Type: int16, Unit: 8/115 °/s, Range: [-28750 to 28750]
temperature – Type: int16, Unit: 1/100 °C, Range: [-2¹⁵ to 2¹⁵ - 1]

This callback is triggered periodically with the period that is set by set_all_data_period. The response values are the acceleration, the magnetic field and the angular velocity for the x, y and z axis as well as the temperature of the IMU Brick.

BrickIMU.CALLBACK_ORIENTATION¶

Function ID:	35
Response:	roll – Type: int16, Unit: 1/100 °, Range: [-18000 to 18000] pitch – Type: int16, Unit: 1/100 °, Range: [-18000 to 18000] yaw – Type: int16, Unit: 1/100 °, Range: [-18000 to 18000]

This callback is triggered periodically with the period that is set by set_orientation_period. The response values are the orientation (roll, pitch and yaw) of the IMU Brick in Euler angles. See get_orientation for details.

BrickIMU.CALLBACK_QUATERNION¶

Function ID:	36
Response:	x – Type: float, Range: [-1.0 to 1.0] y – Type: float, Range: [-1.0 to 1.0] z – Type: float, Range: [-1.0 to 1.0] w – Type: float, Range: [-1.0 to 1.0]

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

Internal Functions¶

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

BrickIMU.get_protocol1_bricklet_name¶

Function ID:	241
Request:	port – Type: char, Range: ['a' to 'b']
Response:	protocol_version – Type: uint8, Range: [0 to 255] firmware_version – Type: uint8[3] 0: major – Type: uint8, Range: [0 to 255] 1: minor – Type: uint8, Range: [0 to 255] 2: revision – Type: uint8, Range: [0 to 255] name – Type: char[40]

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.

BrickIMU.write_bricklet_plugin¶

Function ID:	246
Request:	port – Type: char, Range: ['a' to 'b'] offset – Type: uint8, Range: [0 to 255] chunk – Type: uint8[32], Range: [0 to 255]
Response:	no response

Writes 32 bytes of firmware to the bricklet attached at the given port. The bytes are written to the position offset * 32.

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

BrickIMU.read_bricklet_plugin¶

Function ID:	247
Request:	port – Type: char, Range: ['a' to 'b'] offset – Type: uint8, Range: [0 to 255]
Response:	chunk – Type: uint8[32], Range: [0 to 255]

Reads 32 bytes of firmware from the bricklet attached at the given port. The bytes are read starting at the position offset * 32.

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