Source code for adafruit_lsm9ds1

# SPDX-FileCopyrightText: 2017 Tony DiCola for Adafruit Industries
#
# SPDX-License-Identifier: MIT

"""
`adafruit_lsm9ds1`
====================================================

CircuitPython module for the LSM9DS1 accelerometer, magnetometer, gyroscope.
Based on the driver from:
https://github.com/adafruit/Adafruit_LSM9DS1

See examples/simpletest.py for a demo of the usage.

* Author(s): Tony DiCola

Implementation Notes
--------------------

**Hardware:**

* `Adafruit 9-DOF Accel/Mag/Gyro+Temp Breakout Board - LSM9DS1
  <https://www.adafruit.com/product/3387>`_ (Product ID: 3387)

**Software and Dependencies:**

* Adafruit CircuitPython firmware for the supported boards:
  https://circuitpython.org/downloads

* Adafruit's Bus Device library:
  https://github.com/adafruit/Adafruit_CircuitPython_BusDevice
"""

__version__ = "0.0.0-auto.0"
__repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_LSM9DS1.git"

import time
from math import radians

try:
    import struct
except ImportError:
    import ustruct as struct

import adafruit_bus_device.i2c_device as i2c_device
import adafruit_bus_device.spi_device as spi_device
from micropython import const

# Internal constants and register values:
_LSM9DS1_ADDRESS_ACCELGYRO = const(0x6B)
_LSM9DS1_ADDRESS_MAG = const(0x1E)
_LSM9DS1_XG_ID = const(0b01101000)
_LSM9DS1_MAG_ID = const(0b00111101)
_LSM9DS1_ACCEL_MG_LSB_2G = 0.061
_LSM9DS1_ACCEL_MG_LSB_4G = 0.122
_LSM9DS1_ACCEL_MG_LSB_8G = 0.244
_LSM9DS1_ACCEL_MG_LSB_16G = 0.732
_LSM9DS1_MAG_MGAUSS_4GAUSS = 0.14
_LSM9DS1_MAG_MGAUSS_8GAUSS = 0.29
_LSM9DS1_MAG_MGAUSS_12GAUSS = 0.43
_LSM9DS1_MAG_MGAUSS_16GAUSS = 0.58
_LSM9DS1_GYRO_DPS_DIGIT_245DPS = 0.00875
_LSM9DS1_GYRO_DPS_DIGIT_500DPS = 0.01750
_LSM9DS1_GYRO_DPS_DIGIT_2000DPS = 0.07000
_LSM9DS1_TEMP_LSB_DEGREE_CELSIUS = 8  # 1°C = 8, 25° = 200, etc.
_LSM9DS1_REGISTER_WHO_AM_I_XG = const(0x0F)
_LSM9DS1_REGISTER_CTRL_REG1_G = const(0x10)
_LSM9DS1_REGISTER_CTRL_REG2_G = const(0x11)
_LSM9DS1_REGISTER_CTRL_REG3_G = const(0x12)
_LSM9DS1_REGISTER_TEMP_OUT_L = const(0x15)
_LSM9DS1_REGISTER_TEMP_OUT_H = const(0x16)
_LSM9DS1_REGISTER_STATUS_REG = const(0x17)
_LSM9DS1_REGISTER_OUT_X_L_G = const(0x18)
_LSM9DS1_REGISTER_OUT_X_H_G = const(0x19)
_LSM9DS1_REGISTER_OUT_Y_L_G = const(0x1A)
_LSM9DS1_REGISTER_OUT_Y_H_G = const(0x1B)
_LSM9DS1_REGISTER_OUT_Z_L_G = const(0x1C)
_LSM9DS1_REGISTER_OUT_Z_H_G = const(0x1D)
_LSM9DS1_REGISTER_CTRL_REG4 = const(0x1E)
_LSM9DS1_REGISTER_CTRL_REG5_XL = const(0x1F)
_LSM9DS1_REGISTER_CTRL_REG6_XL = const(0x20)
_LSM9DS1_REGISTER_CTRL_REG7_XL = const(0x21)
_LSM9DS1_REGISTER_CTRL_REG8 = const(0x22)
_LSM9DS1_REGISTER_CTRL_REG9 = const(0x23)
_LSM9DS1_REGISTER_CTRL_REG10 = const(0x24)
_LSM9DS1_REGISTER_OUT_X_L_XL = const(0x28)
_LSM9DS1_REGISTER_OUT_X_H_XL = const(0x29)
_LSM9DS1_REGISTER_OUT_Y_L_XL = const(0x2A)
_LSM9DS1_REGISTER_OUT_Y_H_XL = const(0x2B)
_LSM9DS1_REGISTER_OUT_Z_L_XL = const(0x2C)
_LSM9DS1_REGISTER_OUT_Z_H_XL = const(0x2D)
_LSM9DS1_REGISTER_WHO_AM_I_M = const(0x0F)
_LSM9DS1_REGISTER_CTRL_REG1_M = const(0x20)
_LSM9DS1_REGISTER_CTRL_REG2_M = const(0x21)
_LSM9DS1_REGISTER_CTRL_REG3_M = const(0x22)
_LSM9DS1_REGISTER_CTRL_REG4_M = const(0x23)
_LSM9DS1_REGISTER_CTRL_REG5_M = const(0x24)
_LSM9DS1_REGISTER_STATUS_REG_M = const(0x27)
_LSM9DS1_REGISTER_OUT_X_L_M = const(0x28)
_LSM9DS1_REGISTER_OUT_X_H_M = const(0x29)
_LSM9DS1_REGISTER_OUT_Y_L_M = const(0x2A)
_LSM9DS1_REGISTER_OUT_Y_H_M = const(0x2B)
_LSM9DS1_REGISTER_OUT_Z_L_M = const(0x2C)
_LSM9DS1_REGISTER_OUT_Z_H_M = const(0x2D)
_LSM9DS1_REGISTER_CFG_M = const(0x30)
_LSM9DS1_REGISTER_INT_SRC_M = const(0x31)
_MAGTYPE = True
_XGTYPE = False
_SENSORS_GRAVITY_STANDARD = 9.80665
_SPI_AUTO_INCR = 0x40

# User facing constants/module globals.
ACCELRANGE_2G = 0b00 << 3
ACCELRANGE_16G = 0b01 << 3
ACCELRANGE_4G = 0b10 << 3
ACCELRANGE_8G = 0b11 << 3
MAGGAIN_4GAUSS = 0b00 << 5  # +/- 4 gauss
MAGGAIN_8GAUSS = 0b01 << 5  # +/- 8 gauss
MAGGAIN_12GAUSS = 0b10 << 5  # +/- 12 gauss
MAGGAIN_16GAUSS = 0b11 << 5  # +/- 16 gauss
GYROSCALE_245DPS = 0b00 << 3  # +/- 245 degrees/s rotation
GYROSCALE_500DPS = 0b01 << 3  # +/- 500 degrees/s rotation
GYROSCALE_2000DPS = 0b11 << 3  # +/- 2000 degrees/s rotation


def _twos_comp(val, bits):
    # Convert an unsigned integer in 2's compliment form of the specified bit
    # length to its signed integer value and return it.
    if val & (1 << (bits - 1)) != 0:
        return val - (1 << bits)
    return val


[docs]class LSM9DS1: """Driver for the LSM9DS1 accelerometer, magnetometer, gyroscope.""" # Class-level buffer for reading and writing data with the sensor. # This reduces memory allocations but means the code is not re-entrant or # thread safe! _BUFFER = bytearray(6) def __init__(self): # soft reset & reboot accel/gyro self._write_u8(_XGTYPE, _LSM9DS1_REGISTER_CTRL_REG8, 0x05) # soft reset & reboot magnetometer self._write_u8(_MAGTYPE, _LSM9DS1_REGISTER_CTRL_REG2_M, 0x0C) time.sleep(0.01) # Check ID registers. if ( self._read_u8(_XGTYPE, _LSM9DS1_REGISTER_WHO_AM_I_XG) != _LSM9DS1_XG_ID or self._read_u8(_MAGTYPE, _LSM9DS1_REGISTER_WHO_AM_I_M) != _LSM9DS1_MAG_ID ): raise RuntimeError("Could not find LSM9DS1, check wiring!") # enable gyro continuous self._write_u8(_XGTYPE, _LSM9DS1_REGISTER_CTRL_REG1_G, 0xC0) # on XYZ # Enable the accelerometer continous self._write_u8(_XGTYPE, _LSM9DS1_REGISTER_CTRL_REG5_XL, 0x38) self._write_u8(_XGTYPE, _LSM9DS1_REGISTER_CTRL_REG6_XL, 0xC0) # enable mag continuous self._write_u8(_MAGTYPE, _LSM9DS1_REGISTER_CTRL_REG3_M, 0x00) # Set default ranges for the various sensors self._accel_mg_lsb = None self._mag_mgauss_lsb = None self._gyro_dps_digit = None self.accel_range = ACCELRANGE_2G self.mag_gain = MAGGAIN_4GAUSS self.gyro_scale = GYROSCALE_245DPS @property def accel_range(self): """The accelerometer range. Must be a value of: - ACCELRANGE_2G - ACCELRANGE_4G - ACCELRANGE_8G - ACCELRANGE_16G """ reg = self._read_u8(_XGTYPE, _LSM9DS1_REGISTER_CTRL_REG6_XL) return (reg & 0b00011000) & 0xFF @accel_range.setter def accel_range(self, val): assert val in (ACCELRANGE_2G, ACCELRANGE_4G, ACCELRANGE_8G, ACCELRANGE_16G) reg = self._read_u8(_XGTYPE, _LSM9DS1_REGISTER_CTRL_REG6_XL) reg = (reg & ~(0b00011000)) & 0xFF reg |= val self._write_u8(_XGTYPE, _LSM9DS1_REGISTER_CTRL_REG6_XL, reg) if val == ACCELRANGE_2G: self._accel_mg_lsb = _LSM9DS1_ACCEL_MG_LSB_2G elif val == ACCELRANGE_4G: self._accel_mg_lsb = _LSM9DS1_ACCEL_MG_LSB_4G elif val == ACCELRANGE_8G: self._accel_mg_lsb = _LSM9DS1_ACCEL_MG_LSB_8G elif val == ACCELRANGE_16G: self._accel_mg_lsb = _LSM9DS1_ACCEL_MG_LSB_16G @property def mag_gain(self): """The magnetometer gain. Must be a value of: - MAGGAIN_4GAUSS - MAGGAIN_8GAUSS - MAGGAIN_12GAUSS - MAGGAIN_16GAUSS """ reg = self._read_u8(_MAGTYPE, _LSM9DS1_REGISTER_CTRL_REG2_M) return (reg & 0b01100000) & 0xFF @mag_gain.setter def mag_gain(self, val): assert val in (MAGGAIN_4GAUSS, MAGGAIN_8GAUSS, MAGGAIN_12GAUSS, MAGGAIN_16GAUSS) reg = self._read_u8(_MAGTYPE, _LSM9DS1_REGISTER_CTRL_REG2_M) reg = (reg & ~(0b01100000)) & 0xFF reg |= val self._write_u8(_MAGTYPE, _LSM9DS1_REGISTER_CTRL_REG2_M, reg) if val == MAGGAIN_4GAUSS: self._mag_mgauss_lsb = _LSM9DS1_MAG_MGAUSS_4GAUSS elif val == MAGGAIN_8GAUSS: self._mag_mgauss_lsb = _LSM9DS1_MAG_MGAUSS_8GAUSS elif val == MAGGAIN_12GAUSS: self._mag_mgauss_lsb = _LSM9DS1_MAG_MGAUSS_12GAUSS elif val == MAGGAIN_16GAUSS: self._mag_mgauss_lsb = _LSM9DS1_MAG_MGAUSS_16GAUSS @property def gyro_scale(self): """The gyroscope scale. Must be a value of: * GYROSCALE_245DPS * GYROSCALE_500DPS * GYROSCALE_2000DPS """ reg = self._read_u8(_XGTYPE, _LSM9DS1_REGISTER_CTRL_REG1_G) return (reg & 0b00011000) & 0xFF @gyro_scale.setter def gyro_scale(self, val): assert val in (GYROSCALE_245DPS, GYROSCALE_500DPS, GYROSCALE_2000DPS) reg = self._read_u8(_XGTYPE, _LSM9DS1_REGISTER_CTRL_REG1_G) reg = (reg & ~(0b00011000)) & 0xFF reg |= val self._write_u8(_XGTYPE, _LSM9DS1_REGISTER_CTRL_REG1_G, reg) if val == GYROSCALE_245DPS: self._gyro_dps_digit = _LSM9DS1_GYRO_DPS_DIGIT_245DPS elif val == GYROSCALE_500DPS: self._gyro_dps_digit = _LSM9DS1_GYRO_DPS_DIGIT_500DPS elif val == GYROSCALE_2000DPS: self._gyro_dps_digit = _LSM9DS1_GYRO_DPS_DIGIT_2000DPS
[docs] def read_accel_raw(self): """Read the raw accelerometer sensor values and return it as a 3-tuple of X, Y, Z axis values that are 16-bit unsigned values. If you want the acceleration in nice units you probably want to use the accelerometer property! """ # Read the accelerometer self._read_bytes(_XGTYPE, 0x80 | _LSM9DS1_REGISTER_OUT_X_L_XL, 6, self._BUFFER) raw_x, raw_y, raw_z = struct.unpack_from("<hhh", self._BUFFER[0:6]) return (raw_x, raw_y, raw_z)
@property def acceleration(self): """The accelerometer X, Y, Z axis values as a 3-tuple of :math:`m/s^2` values. """ raw = self.read_accel_raw() return map( lambda x: x * self._accel_mg_lsb / 1000.0 * _SENSORS_GRAVITY_STANDARD, raw )
[docs] def read_mag_raw(self): """Read the raw magnetometer sensor values and return it as a 3-tuple of X, Y, Z axis values that are 16-bit unsigned values. If you want the magnetometer in nice units you probably want to use the magnetometer property! """ # Read the magnetometer self._read_bytes(_MAGTYPE, 0x80 | _LSM9DS1_REGISTER_OUT_X_L_M, 6, self._BUFFER) raw_x, raw_y, raw_z = struct.unpack_from("<hhh", self._BUFFER[0:6]) return (raw_x, raw_y, raw_z)
@property def magnetic(self): """The magnetometer X, Y, Z axis values as a 3-tuple of gauss values. """ raw = self.read_mag_raw() return map(lambda x: x * self._mag_mgauss_lsb / 1000.0, raw)
[docs] def read_gyro_raw(self): """Read the raw gyroscope sensor values and return it as a 3-tuple of X, Y, Z axis values that are 16-bit unsigned values. If you want the gyroscope in nice units you probably want to use the gyroscope property! """ # Read the gyroscope self._read_bytes(_XGTYPE, 0x80 | _LSM9DS1_REGISTER_OUT_X_L_G, 6, self._BUFFER) raw_x, raw_y, raw_z = struct.unpack_from("<hhh", self._BUFFER[0:6]) return (raw_x, raw_y, raw_z)
@property def gyro(self): """The gyroscope X, Y, Z axis values as a 3-tuple of rad/s values. """ raw = self.read_gyro_raw() return map(lambda x: radians(x * self._gyro_dps_digit), raw)
[docs] def read_temp_raw(self): """Read the raw temperature sensor value and return it as a 12-bit signed value. If you want the temperature in nice units you probably want to use the temperature property! """ # Read temp sensor self._read_bytes(_XGTYPE, 0x80 | _LSM9DS1_REGISTER_TEMP_OUT_L, 2, self._BUFFER) temp = ((self._BUFFER[1] << 8) | self._BUFFER[0]) >> 4 return _twos_comp(temp, 12)
@property def temperature(self): """The temperature of the sensor in degrees Celsius.""" # This is just a guess since the starting point (21C here) isn't documented :( # See discussion from: # https://github.com/kriswiner/LSM9DS1/issues/3 temp = self.read_temp_raw() temp = 27.5 + temp / 16 return temp def _read_u8(self, sensor_type, address): # Read an 8-bit unsigned value from the specified 8-bit address. # The sensor_type boolean should be _MAGTYPE when talking to the # magnetometer, or _XGTYPE when talking to the accel or gyro. # MUST be implemented by subclasses! raise NotImplementedError() def _read_bytes(self, sensor_type, address, count, buf): # Read a count number of bytes into buffer from the provided 8-bit # register address. The sensor_type boolean should be _MAGTYPE when # talking to the magnetometer, or _XGTYPE when talking to the accel or # gyro. MUST be implemented by subclasses! raise NotImplementedError() def _write_u8(self, sensor_type, address, val): # Write an 8-bit unsigned value to the specified 8-bit address. # The sensor_type boolean should be _MAGTYPE when talking to the # magnetometer, or _XGTYPE when talking to the accel or gyro. # MUST be implemented by subclasses! raise NotImplementedError()
[docs]class LSM9DS1_I2C(LSM9DS1): """Driver for the LSM9DS1 connect over I2C. :param ~busio.I2C i2c: The I2C bus the device is connected to :param int mag_address: A 8-bit integer that represents the i2c address of the LSM9DS1's magnetometer. Options are limited to :const:`0x1C` or :const:`0x1E` Defaults to :const:`0x1E`. :param int xg_address: A 8-bit integer that represents the i2c address of the LSM9DS1's accelerometer and gyroscope. Options are limited to :const:`0x6A` or :const:`0x6B`. Defaults to :const:`0x6B`. **Quickstart: Importing and using the device** Here is an example of using the :class:`LSM9DS1` class. First you will need to import the libraries to use the sensor .. code-block:: python import board import adafruit_lsm9ds1 Once this is done you can define your `board.I2C` object and define your sensor object .. code-block:: python i2c = board.I2C() # uses board.SCL and board.SDA sensor = adafruit_lsm9ds1.LSM9DS1_I2C(i2c) Now you have access to the :attr:`acceleration`, :attr:`magnetic` :attr:`gyro` and :attr:`temperature` attributes .. code-block:: python acc_x, acc_y, acc_z = sensor.acceleration mag_x, mag_y, mag_z = sensor.magnetic gyro_x, gyro_y, gyro_z = sensor.gyro temp = sensor.temperature """ def __init__( self, i2c, mag_address=_LSM9DS1_ADDRESS_MAG, xg_address=_LSM9DS1_ADDRESS_ACCELGYRO, ): if mag_address in (0x1C, 0x1E) and xg_address in (0x6A, 0x6B): self._mag_device = i2c_device.I2CDevice(i2c, mag_address) self._xg_device = i2c_device.I2CDevice(i2c, xg_address) super().__init__() else: raise ValueError( "address parmeters are incorrect. Read the docs at " "circuitpython.rtfd.io/projects/lsm9ds1/en/latest" "/api.html#adafruit_lsm9ds1.LSM9DS1_I2C" ) def _read_u8(self, sensor_type, address): if sensor_type == _MAGTYPE: device = self._mag_device else: device = self._xg_device with device as i2c: self._BUFFER[0] = address & 0xFF i2c.write_then_readinto( self._BUFFER, self._BUFFER, out_end=1, in_start=1, in_end=2 ) return self._BUFFER[1] def _read_bytes(self, sensor_type, address, count, buf): if sensor_type == _MAGTYPE: device = self._mag_device else: device = self._xg_device with device as i2c: buf[0] = address & 0xFF i2c.write_then_readinto(buf, buf, out_end=1, in_end=count) def _write_u8(self, sensor_type, address, val): if sensor_type == _MAGTYPE: device = self._mag_device else: device = self._xg_device with device as i2c: self._BUFFER[0] = address & 0xFF self._BUFFER[1] = val & 0xFF i2c.write(self._BUFFER, end=2)
[docs]class LSM9DS1_SPI(LSM9DS1): """Driver for the LSM9DS1 connect over SPI. :param ~busio.SPI spi: The SPI bus the device is connected to :param ~digitalio.DigitalInOut mcs: The digital output pin connected to the LSM9DS1's CSM (Chip Select Magnetometer) pin. :param ~digitalio.DigitalInOut xgcs: The digital output pin connected to the LSM9DS1's CSAG (Chip Select Accelerometer/Gyroscope) pin. **Quickstart: Importing and using the device** Here is an example of using the :class:`LSM9DS1` class. First you will need to import the libraries to use the sensor .. code-block:: python import board import adafruit_lsm9ds1 Once this is done you can define your `board.SPI` object and define your sensor object .. code-block:: python spi = board.SPI() sensor = adafruit_lsm9ds1.LSM9DS1_SPI(spi) Now you have access to the :attr:`acceleration`, :attr:`magnetic` :attr:`gyro` and :attr:`temperature` attributes .. code-block:: python acc_x, acc_y, acc_z = sensor.acceleration mag_x, mag_y, mag_z = sensor.magnetic gyro_x, gyro_y, gyro_z = sensor.gyro temp = sensor.temperature """ # pylint: disable=no-member def __init__(self, spi, xgcs, mcs): self._mag_device = spi_device.SPIDevice( spi, mcs, baudrate=200000, phase=1, polarity=1 ) self._xg_device = spi_device.SPIDevice( spi, xgcs, baudrate=200000, phase=1, polarity=1 ) super().__init__() def _read_u8(self, sensor_type, address): if sensor_type == _MAGTYPE: device = self._mag_device else: device = self._xg_device with device as spi: self._BUFFER[0] = (address | 0x80) & 0xFF spi.write(self._BUFFER, end=1) spi.readinto(self._BUFFER, end=1) return self._BUFFER[0] def _read_bytes(self, sensor_type, address, count, buf): if sensor_type == _MAGTYPE: device = self._mag_device address |= _SPI_AUTO_INCR else: device = self._xg_device with device as spi: buf[0] = (address | 0x80) & 0xFF spi.write(buf, end=1) spi.readinto(buf, end=count) def _write_u8(self, sensor_type, address, val): if sensor_type == _MAGTYPE: device = self._mag_device else: device = self._xg_device with device as spi: self._BUFFER[0] = (address & 0x7F) & 0xFF self._BUFFER[1] = val & 0xFF spi.write(self._BUFFER, end=2)