Introduction¶

CircuitPython module for the MPL3115A2 barometric pressure & temperature sensor.

Dependencies¶

This driver depends on:

Please ensure all dependencies are available on the CircuitPython filesystem. This is easily achieved by downloading the Adafruit library and driver bundle.

Installing from PyPI¶

On supported GNU/Linux systems like the Raspberry Pi, you can install the driver locally from PyPI. To install for current user:

pip3 install adafruit-circuitpython-mpl3115a2

To install system-wide (this may be required in some cases):

sudo pip3 install adafruit-circuitpython-mpl3115a2

To install in a virtual environment in your current project:

mkdir project-name && cd project-name
python3 -m venv .env
source .env/bin/activate
pip3 install adafruit-circuitpython-mpl3115a2

Usage Example¶

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

Contributing¶

Contributions are welcome! Please read our Code of Conduct before contributing to help this project stay welcoming.

Documentation¶

For information on building library documentation, please check out this guide.

Table of Contents¶

Simple test¶

Ensure your device works with this simple test.

examples/mpl3115a2_simpletest.py¶

# Simple demo of the MPL3115A2 sensor.
# Will read the pressure and temperature and print them out every second.
# Author: Tony DiCola
import time

import board
import busio

import adafruit_mpl3115a2


# Initialize the I2C bus.
i2c = busio.I2C(board.SCL, board.SDA)

# Initialize the MPL3115A2.
sensor = adafruit_mpl3115a2.MPL3115A2(i2c)
# Alternatively you can specify a different I2C address for the device:
#sensor = adafruit_mpl3115a2.MPL3115A2(i2c, address=0x10)

# You can configure the pressure at sealevel to get better altitude estimates.
# This value has to be looked up from your local weather forecast or meteorlogical
# reports.  It will change day by day and even hour by hour with weather
# changes.  Remember altitude estimation from barometric pressure is not exact!
# Set this to a value in pascals:
sensor.sealevel_pressure = 102250

# Main loop to read the sensor values and print them every second.
while True:
    pressure = sensor.pressure
    print('Pressure: {0:0.3f} pascals'.format(pressure))
    altitude = sensor.altitude
    print('Altitude: {0:0.3f} meters'.format(altitude))
    temperature = sensor.temperature
    print('Temperature: {0:0.3f} degrees Celsius'.format(temperature))
    time.sleep(1.0)

`adafruit_mpl3115a2`¶

CircuitPython module for the MPL3115A2 barometric pressure & temperature sensor. See examples/simpletest.py for a demo of the usage.

Author(s): Tony DiCola

class adafruit_mpl3115a2.MPL3115A2(i2c, *, address=96)¶

Instance of the MPL3115A2 sensor. Must specify the following parameters when creating an instance of this device: - i2c: The I2C bus connected to the sensor.

In addition you can specify the following optional keyword arguments: - address: The I2C address of the device if it’s different from the default.

altitude¶: Read the altitude as calculated based on the sensor pressure and previously configured pressure at sea-level. This will return a value in meters. Set the sea-level pressure by updating the sealevel_pressure property first to get a more accurate altitude value.

pressure¶: Read the barometric pressure detected by the sensor in Pascals.

sealevel_pressure¶: Read and write the pressure at sea-level used to calculate altitude. You must look this up from a local weather or meteorlogical report for the best accuracy. This is a value in Pascals.

temperature¶: Read the temperature as measured by the sensor in degrees Celsius.