CircuitPython Microcontroller Wiring
First wire up a LSM9DS1 to your board exactly as shown on the previous pages for Arduino. You can use either I2C or SPI wiring, although it's recommended to use I2C for simplicity.
I2C
Here's an example of wiring a Feather M0 to the sensor with an I2C connection, either the new classic blue form factor, or the newer revisions either on a breadboard or using the Stemma QT connectors:
It's easy to use the LSM9DS1 sensor with Python or CircuitPython, and the Adafruit CircuitPython LSM9DS1 module. This module allows you to easily write Python code that reads the accelerometer, magnetometer, and gyroscope from the sensor.
You can use this sensor with any CircuitPython microcontroller board or with a computer that has GPIO and Python thanks to Adafruit_Blinka, our CircuitPython-for-Python compatibility library.
SPI
Wiring up the LSM9DS1 to a Feather M0 using SPI is a bit more complicated due to the addition of two sets of Sensor Out and CS pins. Wiring for the newer or older versions of the board are pretty similar
- Board 3V to sensor VIN (Red)
- Board GND to sensor GND (Black)
- Board SCK to sensor SCL (Purple)
- Board MOSI to sensor SDA (Green)
- Board MISO to sensor SDOAG AND sensor DOM (Orange)
- Board D5 to sensor CSAG (Yellow)
- Board D6 to sensor CSM (Blue)
To use the classic blue board with SPI
- Board 3V to sensor VIN (Red)
- Board GND to sensor GND (Black)
- Board SCK to sensor SCL (Purple)
- Board MOSI to sensor SDA (Green)
- Board MISO to sensor SDOAG AND sensor SDOM (Orange)
- Board D5 to sensor CSAG (Yellow)
- Board D6 to sensor CSM (Blue)
Python Computer Wiring
Since there's dozens of Linux computers/boards you can use we will show wiring for Raspberry Pi. For other platforms, please visit the guide for CircuitPython on Linux to see whether your platform is supported.
I2C
- Pi 3V3 to sensor VIN
- Pi GND to sensor GND
- Pi SCLK to sensor SCL
- Pi MOSI to sensor SDA
- Pi MISO to sensor SDOAG AND sensor SDOM
- Pi GPIO5 to sensor CSAG
- Pi GPIO6 to sensor CSM
CircuitPython Installation of LSM9DS1 Library
You'll need to install the Adafruit CircuitPython LSM9DS1 library on your CircuitPython board.
First make sure you are running the latest version of Adafruit CircuitPython for your board.
Next you'll need to install the necessary libraries to use the hardware--carefully follow the steps to find and install these libraries from Adafruit's CircuitPython library bundle. Our introduction guide has a great page on how to install the library bundle for both express and non-express boards.
Remember for non-express boards like the, you'll need to manually install the necessary libraries from the bundle:
- adafruit_lsm9ds1.mpy
- adafruit_bus_device
Before continuing make sure your board's lib folder or root filesystem has the adafruit_lsm9ds1.mpy, and adafruit_bus_device files and folders copied over.
Next connect to the board's serial REPL so you are at the CircuitPython >>> prompt.
CircuitPython & Python Usage
To demonstrate the usage of the sensor we'll initialize it and read the accelerometer, magnetometer, and more from the board's Python REPL.
Run the following code to import the necessary modules and initialize the I2C connection with the sensor:
import board import adafruit_lsm9ds1 i2c = board.I2C() sensor = adafruit_lsm9ds1.LSM9DS1_I2C(i2c)
If you're connected using SPI, run the following code to initialise the SPI connection with the sensor:
import board from digitalio import DigitalInOut, Direction spi = board.SPI() csag = DigitalInOut(board.D5) csag.direction = Direction.OUTPUT csag.value = True csm = DigitalInOut(board.D6) csm.direction = Direction.OUTPUT csm.value = True sensor = adafruit_lsm9ds1.LSM9DS1_SPI(spi, csag, csm)
Now you're ready to read values from the sensor using any of these properties:
- acceleromter - A 3-tuple of X, Y, Z axis accelerometer values in meters/second squared.
- magnetometer - A 3-tuple of X, Y, Z axis magnetometer values in gauss.
- gyroscope - A 3-tuple of X, Y, Z axis gyroscope values in degrees/second.
- temperature - The sensor temperature in degrees Celsius.
print('Acceleration (m/s^2): ({0:0.3f},{1:0.3f},{2:0.3f})'.format(*sensor.accelerometer))
print('Magnetometer (gauss): ({0:0.3f},{1:0.3f},{2:0.3f})'.format(*sensor.magnetometer))
print('Gyroscope (degrees/sec): ({0:0.3f},{1:0.3f},{2:0.3f})'.format(*sensor.gyroscope))
print('Temperature: {0:0.3f}C'.format(sensor.temperature))
In addition you can adjust some properties by getting and setting their values:
- accel_range - The range of the accelerometer, should be a value of ACCELRANGE_2G, ACCELRANGE_4G, ACCELRANGE_8G, or ACCELRANGE_16G from the adafruit_lsm9ds1 module. The default is 2G.
- mag_gain - The gain of the magnetometer, should be a value of MAGGAIN_4GAUSS, MAGGAIN_8GAUSS, MAGGAIN_12GAUSS, or MAGGAIN_16GAUSS from the adafruit_lsm9ds1 module. The default is 4 gauss.
- gyro_scale - The scale of the gyroscope, should be a value of GYROSCALE_245DPS, GYROSCALE_500DPS, or GYROSCALE_2000DPS from the adafruit_lsm9ds1 module. The default is 245 DPS.
sensor.accel_range = adafruit_lsm9ds1.ACCELRANGE_4G sensor.mag_gain = adafruit_lsm9ds1.MAGGAIN_8GAUSS sensor.gyro_scale = adafruit_lsm9ds1.GYROSCALE_500DPS
See the simpletest.py example for a complete demo of printing the accelerometer, magnetometer, gyroscope every second. Save this as code.py on the board and examine the REPL output to see the range printed every second.
That's all there is to using the LSM9DS1 with CircuitPython!
# SPDX-FileCopyrightText: 2021 ladyada for Adafruit Industries
# SPDX-License-Identifier: MIT
# Simple demo of the LSM9DS1 accelerometer, magnetometer, gyroscope.
# Will print the acceleration, magnetometer, and gyroscope values every second.
import time
import board
import adafruit_lsm9ds1
# Create sensor object, communicating over the board's default I2C bus
i2c = board.I2C() # uses board.SCL and board.SDA
# i2c = board.STEMMA_I2C() # For using the built-in STEMMA QT connector on a microcontroller
sensor = adafruit_lsm9ds1.LSM9DS1_I2C(i2c)
# SPI connection:
# from digitalio import DigitalInOut, Direction
# spi = board.SPI()
# csag = DigitalInOut(board.D5)
# csag.direction = Direction.OUTPUT
# csag.value = True
# csm = DigitalInOut(board.D6)
# csm.direction = Direction.OUTPUT
# csm.value = True
# sensor = adafruit_lsm9ds1.LSM9DS1_SPI(spi, csag, csm)
# Main loop will read the acceleration, magnetometer, gyroscope, Temperature
# values every second and print them out.
while True:
# Read acceleration, magnetometer, gyroscope, temperature.
accel_x, accel_y, accel_z = sensor.acceleration
mag_x, mag_y, mag_z = sensor.magnetic
gyro_x, gyro_y, gyro_z = sensor.gyro
temp = sensor.temperature
# Print values.
print(
"Acceleration (m/s^2): ({0:0.3f},{1:0.3f},{2:0.3f})".format(
accel_x, accel_y, accel_z
)
)
print(
"Magnetometer (gauss): ({0:0.3f},{1:0.3f},{2:0.3f})".format(mag_x, mag_y, mag_z)
)
print(
"Gyroscope (rad/sec): ({0:0.3f},{1:0.3f},{2:0.3f})".format(
gyro_x, gyro_y, gyro_z
)
)
print("Temperature: {0:0.3f}C".format(temp))
# Delay for a second.
time.sleep(1.0)
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