This is the description of the Modbus protocol for the IMU Bricklet 3.0. General information and technical specifications for the IMU Bricklet 3.0 are summarized in its hardware description.
A general description of the Modbus protocol structure can be found here.
BrickletIMUV3.
get_orientation
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Returns the current orientation (heading, roll, pitch) of the IMU Brick as independent Euler angles. Note that Euler angles always experience a gimbal lock. We recommend that you use quaternions instead, if you need the absolute orientation.
If you want to get the orientation periodically, it is recommended
to use the CALLBACK_ORIENTATION
callback and set the period with
set_orientation_callback_configuration
.
BrickletIMUV3.
get_linear_acceleration
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Returns the linear acceleration of the IMU Brick for the
x, y and z axis. The acceleration is in the range configured with
set_sensor_configuration
.
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 get_gravity_vector
.
If you want to get the linear acceleration periodically, it is recommended
to use the CALLBACK_LINEAR_ACCELERATION
callback and set the period with
set_linear_acceleration_callback_configuration
.
BrickletIMUV3.
get_gravity_vector
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Returns the current gravity vector of the IMU Brick for the x, y and z axis.
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 get_linear_acceleration
.
If you want to get the gravity vector periodically, it is recommended
to use the CALLBACK_GRAVITY_VECTOR
callback and set the period with
set_gravity_vector_callback_configuration
.
BrickletIMUV3.
get_quaternion
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Returns the current orientation (w, x, y, z) of the IMU Brick as quaternions.
You have to divide the return 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 CALLBACK_QUATERNION
callback and set the period with
set_quaternion_callback_configuration
.
BrickletIMUV3.
get_all_data
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Return all of the available data of the IMU Brick.
get_acceleration
)get_magnetic_field
)get_angular_velocity
)get_orientation
)get_quaternion
)get_linear_acceleration
)get_gravity_vector
)get_temperature
)The calibration status consists of four pairs of two bits. Each pair of bits represents the status of the current calibration.
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 CALLBACK_ALL_DATA
callback and set the period with
set_all_data_callback_configuration
.
BrickletIMUV3.
get_acceleration
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Returns the calibrated acceleration from the accelerometer for the
x, y and z axis. The acceleration is in the range configured with
set_sensor_configuration
.
If you want to get the acceleration periodically, it is recommended
to use the CALLBACK_ACCELERATION
callback and set the period with
set_acceleration_callback_configuration
.
BrickletIMUV3.
get_magnetic_field
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
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_callback_configuration
.
BrickletIMUV3.
get_angular_velocity
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Returns the calibrated angular velocity from the gyroscope for the
x, y and z axis. The angular velocity is in the range configured with
set_sensor_configuration
.
If you want to get the angular velocity periodically, it is recommended
to use the CALLBACK_ANGULAR_VELOCITY
acallback nd set the period with
set_angular_velocity_callback_configuration
.
BrickletIMUV3.
get_temperature
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Returns the temperature of the IMU Brick. The temperature is measured in the core of the BNO055 IC, it is not the ambient temperature
BrickletIMUV3.
save_calibration
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
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.
BrickletIMUV3.
set_sensor_configuration
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
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 following meanings are defined for the elements of this function:
For magnetometer_rate:
For gyroscope_range:
For gyroscope_bandwidth:
For accelerometer_range:
For accelerometer_bandwidth:
BrickletIMUV3.
get_sensor_configuration
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Returns the sensor configuration as set by set_sensor_configuration
.
The following meanings are defined for the elements of this function:
For magnetometer_rate:
For gyroscope_range:
For gyroscope_bandwidth:
For accelerometer_range:
For accelerometer_bandwidth:
BrickletIMUV3.
set_sensor_fusion_mode
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
If the fusion mode is turned off, the functions get_acceleration
,
get_magnetic_field
and get_angular_velocity
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.
The following meanings are defined for the elements of this function:
For mode:
BrickletIMUV3.
get_sensor_fusion_mode
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Returns the sensor fusion mode as set by set_sensor_fusion_mode
.
The following meanings are defined for the elements of this function:
For mode:
BrickletIMUV3.
get_spitfp_error_count
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Returns the error count for the communication between Brick and Bricklet.
The errors are divided into
The errors counts are for errors that occur on the Bricklet side. All Bricks have a similar function that returns the errors on the Brick side.
BrickletIMUV3.
set_status_led_config
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Sets the status LED configuration. By default the LED shows communication traffic between Brick and Bricklet, it flickers once for every 10 received data packets.
You can also turn the LED permanently on/off or show a heartbeat.
If the Bricklet is in bootloader mode, the LED is will show heartbeat by default.
The following meanings are defined for the elements of this function:
For config:
BrickletIMUV3.
get_status_led_config
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Returns the configuration as set by set_status_led_config
The following meanings are defined for the elements of this function:
For config:
BrickletIMUV3.
get_chip_temperature
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Returns the temperature as measured inside the microcontroller. The value returned is not the ambient temperature!
The temperature is only proportional to the real temperature and it has bad accuracy. Practically it is only useful as an indicator for temperature changes.
BrickletIMUV3.
reset
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Calling this function will reset the Bricklet. All configurations will be lost.
After a reset you have to create new device objects, calling functions on the existing ones will result in undefined behavior!
BrickletIMUV3.
get_identity
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Returns the UID, the UID where the Bricklet is connected to, the position, the hardware and firmware version as well as the device identifier.
The position can be 'a', 'b', 'c', 'd', 'e', 'f', 'g' or 'h' (Bricklet Port). A Bricklet connected to an Isolator Bricklet is always at position 'z'.
The device identifier numbers can be found here.
BrickletIMUV3.
set_acceleration_callback_configuration
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
The period is the period with which the CALLBACK_ACCELERATION
callback
is triggered periodically. A value of 0 turns the callback off.
If the value has to change-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.
If it is set to false, the callback is continuously triggered with the period, independent of the value.
BrickletIMUV3.
get_acceleration_callback_configuration
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Returns the callback configuration as set by set_acceleration_callback_configuration
.
BrickletIMUV3.
set_magnetic_field_callback_configuration
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
The period is the period with which the CALLBACK_MAGNETIC_FIELD
callback
is triggered periodically. A value of 0 turns the callback off.
If the value has to change-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.
If it is set to false, the callback is continuously triggered with the period, independent of the value.
BrickletIMUV3.
get_magnetic_field_callback_configuration
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Returns the callback configuration as set by set_magnetic_field_callback_configuration
.
BrickletIMUV3.
set_angular_velocity_callback_configuration
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
The period is the period with which the CALLBACK_ANGULAR_VELOCITY
callback
is triggered periodically. A value of 0 turns the callback off.
If the value has to change-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.
If it is set to false, the callback is continuously triggered with the period, independent of the value.
BrickletIMUV3.
get_angular_velocity_callback_configuration
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Returns the callback configuration as set by set_angular_velocity_callback_configuration
.
BrickletIMUV3.
set_temperature_callback_configuration
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
The period is the period with which the CALLBACK_TEMPERATURE
callback
is triggered periodically. A value of 0 turns the callback off.
If the value has to change-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.
If it is set to false, the callback is continuously triggered with the period, independent of the value.
BrickletIMUV3.
get_temperature_callback_configuration
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Returns the callback configuration as set by set_temperature_callback_configuration
.
BrickletIMUV3.
set_orientation_callback_configuration
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
The period is the period with which the CALLBACK_ORIENTATION
callback
is triggered periodically. A value of 0 turns the callback off.
If the value has to change-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.
If it is set to false, the callback is continuously triggered with the period, independent of the value.
BrickletIMUV3.
get_orientation_callback_configuration
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Returns the callback configuration as set by set_orientation_callback_configuration
.
BrickletIMUV3.
set_linear_acceleration_callback_configuration
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
The period is the period with which the CALLBACK_LINEAR_ACCELERATION
callback
is triggered periodically. A value of 0 turns the callback off.
If the value has to change-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.
If it is set to false, the callback is continuously triggered with the period, independent of the value.
BrickletIMUV3.
get_linear_acceleration_callback_configuration
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Returns the callback configuration as set by set_linear_acceleration_callback_configuration
.
BrickletIMUV3.
set_gravity_vector_callback_configuration
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
The period is the period with which the CALLBACK_GRAVITY_VECTOR
callback
is triggered periodically. A value of 0 turns the callback off.
If the value has to change-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.
If it is set to false, the callback is continuously triggered with the period, independent of the value.
BrickletIMUV3.
get_gravity_vector_callback_configuration
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Returns the callback configuration as set by set_gravity_vector_callback_configuration
.
BrickletIMUV3.
set_quaternion_callback_configuration
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
The period is the period with which the CALLBACK_QUATERNION
callback
is triggered periodically. A value of 0 turns the callback off.
If the value has to change-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.
If it is set to false, the callback is continuously triggered with the period, independent of the value.
BrickletIMUV3.
get_quaternion_callback_configuration
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Returns the callback configuration as set by set_quaternion_callback_configuration
.
BrickletIMUV3.
set_all_data_callback_configuration
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
The period is the period with which the CALLBACK_ALL_DATA
callback
is triggered periodically. A value of 0 turns the callback off.
If the value has to change-parameter is set to true, the callback is only triggered after the value has changed. If the value didn't change within the period, the callback is triggered immediately on change.
If it is set to false, the callback is continuously triggered with the period, independent of the value.
BrickletIMUV3.
get_all_data_callback_configuration
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Returns the callback configuration as set by set_all_data_callback_configuration
.
BrickletIMUV3.
CALLBACK_ACCELERATION
¶Function ID: |
|
---|---|
Response: |
|
This callback is triggered periodically with the period that is set by
set_acceleration_callback_configuration
. The response values are the acceleration
for the x, y and z axis.
BrickletIMUV3.
CALLBACK_MAGNETIC_FIELD
¶Function ID: |
|
---|---|
Response: |
|
This callback is triggered periodically with the period that is set by
set_magnetic_field_callback_configuration
. The response values are the magnetic
field for the x, y and z axis.
BrickletIMUV3.
CALLBACK_ANGULAR_VELOCITY
¶Function ID: |
|
---|---|
Response: |
|
This callback is triggered periodically with the period that is set by
set_angular_velocity_callback_configuration
. The response values are the angular
velocity for the x, y and z axis.
BrickletIMUV3.
CALLBACK_TEMPERATURE
¶Function ID: |
|
---|---|
Response: |
|
This callback is triggered periodically with the period that is set by
set_temperature_callback_configuration
. The response value is the temperature.
BrickletIMUV3.
CALLBACK_LINEAR_ACCELERATION
¶Function ID: |
|
---|---|
Response: |
|
This callback is triggered periodically with the period that is set by
set_linear_acceleration_callback_configuration
. The response values are the
linear acceleration for the x, y and z axis.
BrickletIMUV3.
CALLBACK_GRAVITY_VECTOR
¶Function ID: |
|
---|---|
Response: |
|
This callback is triggered periodically with the period that is set by
set_gravity_vector_callback_configuration
. The response values gravity vector
for the x, y and z axis.
BrickletIMUV3.
CALLBACK_ORIENTATION
¶Function ID: |
|
---|---|
Response: |
|
This callback is triggered periodically with the period that is set by
set_orientation_callback_configuration
. The response values are the orientation
(heading (yaw), roll, pitch) of the IMU Brick in Euler angles. See
get_orientation
for details.
BrickletIMUV3.
CALLBACK_QUATERNION
¶Function ID: |
|
---|---|
Response: |
|
This callback is triggered periodically with the period that is set by
set_quaternion_callback_configuration
. The response values are the orientation
(w, x, y, z) of the IMU Brick in quaternions. See get_quaternion
for details.
BrickletIMUV3.
CALLBACK_ALL_DATA
¶Function ID: |
|
---|---|
Response: |
|
This callback is triggered periodically with the period that is set by
set_all_data_callback_configuration
. The response values are as for
get_all_data
.
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.
BrickletIMUV3.
set_bootloader_mode
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Sets the bootloader mode and returns the status after the requested mode change was instigated.
You can change from bootloader mode to firmware mode and vice versa. A change from bootloader mode to firmware mode will only take place if the entry function, device identifier and CRC are present and correct.
This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.
The following meanings are defined for the elements of this function:
For mode:
For status:
BrickletIMUV3.
get_bootloader_mode
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Returns the current bootloader mode, see set_bootloader_mode
.
The following meanings are defined for the elements of this function:
For mode:
BrickletIMUV3.
set_write_firmware_pointer
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Sets the firmware pointer for write_firmware
. The pointer has
to be increased by chunks of size 64. The data is written to flash
every 4 chunks (which equals to one page of size 256).
This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.
BrickletIMUV3.
write_firmware
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Writes 64 Bytes of firmware at the position as written by
set_write_firmware_pointer
before. The firmware is written
to flash every 4 chunks.
You can only write firmware in bootloader mode.
This function is used by Brick Viewer during flashing. It should not be necessary to call it in a normal user program.
BrickletIMUV3.
write_uid
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Writes a new UID into flash. If you want to set a new UID you have to decode the Base58 encoded UID string into an integer first.
We recommend that you use Brick Viewer to change the UID.
BrickletIMUV3.
read_uid
¶Function ID: |
|
---|---|
Request: |
|
Response: |
|
Returns the current UID as an integer. Encode as Base58 to get the usual string version.