adafruit_lis331

A library for the ST LIS331 family of high-g 3-axis accelerometers

  • Author(s): Bryan Siepert

Implementation Notes

Hardware:

Software and Dependencies:

class adafruit_lis331.LIS331(i2c_bus: I2C, address: int = 24)

Base class for the LIS331 family of 3-axis accelerometers. Cannot be instantiated directly

param ~busio.I2C i2c_bus:

The I2C bus the LIS331 is connected to.

param address:

The I2C device address. Defaults to 0x18

property lpf_cutoff: int

The frequency above which signals will be filtered out

property hpf_reference: int

The reference value to offset measurements when using the High-pass filter. To use, use_reference must be set to true when enabling the high-pass filter. The value is a signed 8-bit number from -128 to 127. The value of each increment of 1 depends on the currently set measurement range and is approximate: #pylint: disable=line-too-long

Range

Incremental value (LSB value)

LIS331HHRange.RANGE_6G or H3LIS331Range.RANGE_100G

~16mg

LIS331HHRange.RANGE_12G or H3LIS331Range.RANGE_200G

~31mg

LIS331HHRange.RANGE_24G or H3LIS331Range.RANGE_400G

~63mg

#pylint: enable=line-too-long

zero_hpf() → None

When the high-pass filter is enabled with use_reference=False, calling zero_hpf() will set all measurements to zero immediately, avoiding the normal settling time seen when using the high-pass filter without a hpf_reference()

enable_hpf(enabled: bool = True, cutoff: int = 0, use_reference: bool = False) → None

Enable or disable the high-pass filter.

Parameters:

  • enabled – Enable or disable the filter. Default is True to enable

  • cutoff (RateDivisor) – A RateDivisor to set the high-pass cutoff frequency. Default is RateDivisor.ODR_DIV_50. See RateDivisor for more information

  • use_reference – Determines if the filtered measurements are offset by a reference value. Default is false.

See section 4 of the LIS331DLH application note for more information LIS331DLH application note for more information

property data_rate: float

Select the rate at which the accelerometer takes measurements. Must be a Rate

property mode: int

The Mode power mode that the sensor is set to, as determined by the current data_rate. To set the mode, use data_rate and the appropriate Rate

property range: int

Adjusts the range of values that the sensor can measure, Note that larger ranges will be less accurate. Must be a H3LIS331Range or LIS331HHRange

property acceleration: Tuple[int, int, int]

The x, y, z acceleration values returned in a 3-tuple and are in \(m / s ^ 2\).

class adafruit_lis331.LIS331HH(i2c_bus: I2C, address: int = 24)

Driver for the LIS331HH 3-axis high-g accelerometer.

Parameters:

  • i2c_bus (I2C) – The I2C bus the LIS331 is connected to.

  • address – The I2C device address. Defaults to 0x18

Quickstart: Importing and using the device

Here is an example of using the LIS331 class. First you will need to import the libraries to use the sensor

import board
import adafruit_lis331

Once this is done you can define your board.I2C object and define your sensor object

i2c = board.I2C()  # uses board.SCL and board.SDA
lis = adafruit_lis331.LIS331HH(i2c)

Now you have access to the acceleration attribute

acceleration = lis.acceleration
class adafruit_lis331.H3LIS331(i2c_bus: I2C, address: int = 24)

Driver for the H3LIS331 3-axis high-g accelerometer.

Parameters:

  • i2c_bus (I2C) – The I2C bus the LIS331 is connected to.

  • address – The I2C slave address of the sensor. Defaults to 0x18

Quickstart: Importing and using the device

Here is an example of using the LIS331 class. First you will need to import the libraries to use the sensor

import board
import adafruit_lis331

Once this is done you can define your board.I2C object and define your sensor object

i2c = board.I2C()  # uses board.SCL and board.SDA
lis = adafruit_lis331.H3LIS331(i2c)

Now you have access to the acceleration attribute

acceleration = lis.acceleration