mpu9250.py

# Copyright (c) 2018-2020 Mika Tuupola
#
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# 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 copied 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
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# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
# SOFTWARE.

# https://github.com/tuupola/micropython-mpu9250

"""
MicroPython I2C driver for MPU9250 9-axis motion tracking device
"""

# pylint: disable=import-error
from micropython import const
from mpu6500 import MPU6500
from ak8963 import AK8963
# pylint: enable=import-error

__version__ = "0.3.0"

# Used for enabling and disabling the I2C bypass access
_INT_PIN_CFG = const(0x37)
_I2C_BYPASS_MASK = const(0b00000010)
_I2C_BYPASS_EN = const(0b00000010)
_I2C_BYPASS_DIS = const(0b00000000)

class MPU9250:
    """Class which provides interface to MPU9250 9-axis motion tracking device."""
    def __init__(self, i2c, mpu6500 = None, ak8963 = None):
        if mpu6500 is None:
            self.mpu6500 = MPU6500(i2c)
        else:
            self.mpu6500 = mpu6500

        # Enable I2C bypass to access AK8963 directly.
        char = self.mpu6500._register_char(_INT_PIN_CFG)
        char &= ~_I2C_BYPASS_MASK # clear I2C bits
        char |= _I2C_BYPASS_EN
        self.mpu6500._register_char(_INT_PIN_CFG, char)

        if ak8963 is None:
            self.ak8963 = AK8963(i2c)
        else:
            self.ak8963 = ak8963

    @property
    def acceleration(self):
        """
        Acceleration measured by the sensor. By default will return a
        3-tuple of X, Y, Z axis values in m/s^2 as floats. To get values in g
        pass `accel_fs=SF_G` parameter to the MPU6500 constructor.
        """
        try:
            return self.mpu6500.acceleration
        except OSError as e:
            print(str(e))
            return self.acceleration

    @property
    def gyro(self):
        """
        Gyro measured by the sensor. By default will return a 3-tuple of
        X, Y, Z axis values in rad/s as floats. To get values in deg/s pass
        `gyro_sf=SF_DEG_S` parameter to the MPU6500 constructor.
        """
        try:
            return self.mpu6500.gyro
        except OSError as e:
            print(str(e))
            return self.gyro

    @property
    def temperature(self):
        """
        Die temperature in celcius as a float.
        """
        try:
            return self.mpu6500.temperature
        except OSError as e:
            print(str(e))
            return self.temperature

    @property
    def magnetic(self):
        """
        X, Y, Z axis micro-Tesla (uT) as floats.
        """
        try:
            return self.ak8963.magnetic
        except OSError as e:
            print(str(e))
            return self.magnetic

    @property
    def whoami(self):
        return self.mpu6500.whoami

    def __enter__(self):
        return self

    def __exit__(self, exception_type, exception_value, traceback):
        pass