# The MIT License (MIT)
#
# Copyright (c) 2017 Radomir Dopieralski for Adafruit Industries.
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.
"""
``adafruit_bno055`` - Adafruit 9-DOF Absolute Orientation IMU Fusion Breakout - BNO055
=======================================================================================
This is a CircuitPython driver for the Bosch BNO055 nine degree of freedom
inertial measurement unit module with sensor fusion.
* Author(s): Radomir Dopieralski
"""
import time
from micropython import const
from adafruit_bus_device.i2c_device import I2CDevice
from adafruit_register.i2c_struct import Struct, UnaryStruct
__version__ = "0.0.0-auto.0"
__repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_BNO055.git"
_CHIP_ID = const(0xA0)
CONFIG_MODE = const(0x00)
ACCONLY_MODE = const(0x01)
MAGONLY_MODE = const(0x02)
GYRONLY_MODE = const(0x03)
ACCMAG_MODE = const(0x04)
ACCGYRO_MODE = const(0x05)
MAGGYRO_MODE = const(0x06)
AMG_MODE = const(0x07)
IMUPLUS_MODE = const(0x08)
COMPASS_MODE = const(0x09)
M4G_MODE = const(0x0A)
NDOF_FMC_OFF_MODE = const(0x0B)
NDOF_MODE = const(0x0C)
_POWER_NORMAL = const(0x00)
_POWER_LOW = const(0x01)
_POWER_SUSPEND = const(0x02)
_MODE_REGISTER = const(0x3D)
_PAGE_REGISTER = const(0x07)
_CALIBRATION_REGISTER = const(0x35)
_OFFSET_ACCEL_REGISTER = const(0x55)
_OFFSET_MAGNET_REGISTER = const(0x5B)
_OFFSET_GYRO_REGISTER = const(0x61)
_RADIUS_ACCEL_REGISTER = const(0x67)
_RADIUS_MAGNET_REGISTER = const(0x69)
_TRIGGER_REGISTER = const(0x3F)
_POWER_REGISTER = const(0x3E)
_ID_REGISTER = const(0x00)
class _ScaledReadOnlyStruct(Struct): # pylint: disable=too-few-public-methods
def __init__(self, register_address, struct_format, scale):
super(_ScaledReadOnlyStruct, self).__init__(register_address, struct_format)
self.scale = scale
def __get__(self, obj, objtype=None):
result = super(_ScaledReadOnlyStruct, self).__get__(obj, objtype)
return tuple(self.scale * v for v in result)
def __set__(self, obj, value):
raise NotImplementedError()
class _ReadOnlyUnaryStruct(UnaryStruct): # pylint: disable=too-few-public-methods
def __set__(self, obj, value):
raise NotImplementedError()
class _ModeStruct(Struct): # pylint: disable=too-few-public-methods
def __init__(self, register_address, struct_format, mode):
super().__init__(register_address, struct_format)
self.mode = mode
def __get__(self, obj, objtype=None):
last_mode = obj.mode
obj.mode = self.mode
result = super().__get__(obj, objtype)
obj.mode = last_mode
# single value comes back as a one-element tuple
return result[0] if isinstance(result, tuple) and len(result) == 1 else result
def __set__(self, obj, value):
last_mode = obj.mode
obj.mode = self.mode
# underlying __set__() expects a tuple
set_val = value if isinstance(value, tuple) else (value,)
super().__set__(obj, set_val)
obj.mode = last_mode
[docs]class BNO055:
"""
Driver for the BNO055 9DOF IMU sensor.
"""
_temperature = _ReadOnlyUnaryStruct(0x34, "b")
_acceleration = _ScaledReadOnlyStruct(0x08, "<hhh", 1 / 100)
_magnetic = _ScaledReadOnlyStruct(0x0E, "<hhh", 1 / 16)
_gyro = _ScaledReadOnlyStruct(0x14, "<hhh", 0.001090830782496456)
_euler = _ScaledReadOnlyStruct(0x1A, "<hhh", 1 / 16)
_quaternion = _ScaledReadOnlyStruct(0x20, "<hhhh", 1 / (1 << 14))
_linear_acceleration = _ScaledReadOnlyStruct(0x28, "<hhh", 1 / 100)
_gravity = _ScaledReadOnlyStruct(0x2E, "<hhh", 1 / 100)
offsets_accelerometer = _ModeStruct(_OFFSET_ACCEL_REGISTER, "<hhh", CONFIG_MODE)
"""Calibration offsets for the accelerometer"""
offsets_magnetometer = _ModeStruct(_OFFSET_MAGNET_REGISTER, "<hhh", CONFIG_MODE)
"""Calibration offsets for the magnetometer"""
offsets_gyroscope = _ModeStruct(_OFFSET_GYRO_REGISTER, "<hhh", CONFIG_MODE)
"""Calibration offsets for the gyroscope"""
radius_accelerometer = _ModeStruct(_RADIUS_ACCEL_REGISTER, "<h", CONFIG_MODE)
"""Radius for accelerometer (cm?)"""
radius_magnetometer = _ModeStruct(_RADIUS_MAGNET_REGISTER, "<h", CONFIG_MODE)
"""Radius for magnetometer (cm?)"""
def __init__(self, i2c, address=0x28):
self.i2c_device = I2CDevice(i2c, address)
self.buffer = bytearray(2)
chip_id = self._read_register(_ID_REGISTER)
if chip_id != _CHIP_ID:
raise RuntimeError("bad chip id (%x != %x)" % (chip_id, _CHIP_ID))
self._reset()
self._write_register(_POWER_REGISTER, _POWER_NORMAL)
self._write_register(_PAGE_REGISTER, 0x00)
self._write_register(_TRIGGER_REGISTER, 0x00)
time.sleep(0.01)
self.mode = NDOF_MODE
time.sleep(0.01)
def _write_register(self, register, value):
self.buffer[0] = register
self.buffer[1] = value
with self.i2c_device as i2c:
i2c.write(self.buffer)
def _read_register(self, register):
self.buffer[0] = register
with self.i2c_device as i2c:
i2c.write_then_readinto(self.buffer, self.buffer, out_end=1, in_start=1)
return self.buffer[1]
def _reset(self):
"""Resets the sensor to default settings."""
self.mode = CONFIG_MODE
try:
self._write_register(_TRIGGER_REGISTER, 0x20)
except OSError: # error due to the chip resetting
pass
# wait for the chip to reset (650 ms typ.)
time.sleep(0.7)
@property
def mode(self):
"""
Switch the mode of operation and return the previous mode.
Mode of operation defines which sensors are enabled and whether the
measurements are absolute or relative.
If a sensor is disabled, it will return an empty tuple.
legend: x=on, -=off
+------------------+-------+---------+------+----------+
| Mode | Accel | Compass | Gyro | Absolute |
+==================+=======+=========+======+==========+
| CONFIG_MODE | - | - | - | - |
+------------------+-------+---------+------+----------+
| ACCONLY_MODE | X | - | - | - |
+------------------+-------+---------+------+----------+
| MAGONLY_MODE | - | X | - | - |
+------------------+-------+---------+------+----------+
| GYRONLY_MODE | - | - | X | - |
+------------------+-------+---------+------+----------+
| ACCMAG_MODE | X | X | - | - |
+------------------+-------+---------+------+----------+
| ACCGYRO_MODE | X | - | X | - |
+------------------+-------+---------+------+----------+
| MAGGYRO_MODE | - | X | X | - |
+------------------+-------+---------+------+----------+
| AMG_MODE | X | X | X | - |
+------------------+-------+---------+------+----------+
| IMUPLUS_MODE | X | - | X | - |
+------------------+-------+---------+------+----------+
| COMPASS_MODE | X | X | - | X |
+------------------+-------+---------+------+----------+
| M4G_MODE | X | X | - | - |
+------------------+-------+---------+------+----------+
| NDOF_FMC_OFF_MODE| X | X | X | X |
+------------------+-------+---------+------+----------+
| NDOF_MODE | X | X | X | X |
+------------------+-------+---------+------+----------+
The default mode is ``NDOF_MODE``.
"""
return self._read_register(_MODE_REGISTER)
@mode.setter
def mode(self, new_mode):
self._write_register(_MODE_REGISTER, CONFIG_MODE) # Empirically necessary
time.sleep(0.02) # Datasheet table 3.6
if new_mode != CONFIG_MODE:
self._write_register(_MODE_REGISTER, new_mode)
time.sleep(0.01) # Table 3.6
@property
def calibration_status(self):
"""Tuple containing sys, gyro, accel, and mag calibration data."""
calibration_data = self._read_register(_CALIBRATION_REGISTER)
sys = (calibration_data >> 6) & 0x03
gyro = (calibration_data >> 4) & 0x03
accel = (calibration_data >> 2) & 0x03
mag = calibration_data & 0x03
return sys, gyro, accel, mag
@property
def calibrated(self):
"""Boolean indicating calibration status."""
sys, gyro, accel, mag = self.calibration_status
return sys == gyro == accel == mag == 0x03
@property
def external_crystal(self):
"""Switches the use of external crystal on or off."""
last_mode = self.mode
self.mode = CONFIG_MODE
self._write_register(_PAGE_REGISTER, 0x00)
value = self._read_register(_TRIGGER_REGISTER)
self.mode = last_mode
return value == 0x80
@external_crystal.setter
def use_external_crystal(self, value):
last_mode = self.mode
self.mode = CONFIG_MODE
self._write_register(_PAGE_REGISTER, 0x00)
self._write_register(_TRIGGER_REGISTER, 0x80 if value else 0x00)
self.mode = last_mode
time.sleep(0.01)
@property
def temperature(self):
"""Measures the temperature of the chip in degrees Celsius."""
return self._temperature
@property
def acceleration(self):
"""Gives the raw accelerometer readings, in m/s.
Returns an empty tuple of length 3 when this property has been disabled by the current mode.
"""
if self.mode not in [0x00, 0x02, 0x03, 0x06]:
return self._acceleration
return (None, None, None)
@property
def magnetic(self):
"""Gives the raw magnetometer readings in microteslas.
Returns an empty tuple of length 3 when this property has been disabled by the current mode.
"""
if self.mode not in [0x00, 0x03, 0x05, 0x08]:
return self._magnetic
return (None, None, None)
@property
def gyro(self):
"""Gives the raw gyroscope reading in radians per second.
Returns an empty tuple of length 3 when this property has been disabled by the current mode.
"""
if self.mode not in [0x00, 0x01, 0x02, 0x04, 0x09, 0x0A]:
return self._gyro
return (None, None, None)
@property
def euler(self):
"""Gives the calculated orientation angles, in degrees.
Returns an empty tuple of length 3 when this property has been disabled by the current mode.
"""
if self.mode in [0x09, 0x0B, 0x0C]:
return self._euler
return (None, None, None)
@property
def quaternion(self):
"""Gives the calculated orientation as a quaternion.
Returns an empty tuple of length 3 when this property has been disabled by the current mode.
"""
if self.mode in [0x09, 0x0B, 0x0C]:
return self._quaternion
return (None, None, None, None)
@property
def linear_acceleration(self):
"""Returns the linear acceleration, without gravity, in m/s.
Returns an empty tuple of length 3 when this property has been disabled by the current mode.
"""
if self.mode in [0x09, 0x0B, 0x0C]:
return self._linear_acceleration
return (None, None, None)
@property
def gravity(self):
"""Returns the gravity vector, without acceleration in m/s.
Returns an empty tuple of length 3 when this property has been disabled by the current mode.
"""
if self.mode in [0x09, 0x0B, 0x0C]:
return self._gravity
return (None, None, None)