It's easy to use the MPRLS sensor with Python or CircuitPython and the Adafruit CircuitPython MPRLS module. This module allows you to easily write Python code that reads the pressure 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.
CircuitPython Microcontroller Wiring
First wire up an MPRLS to your board exactly as shown on the previous pages for Arduino. You can use I2C. Here's an example of wiring a Feather M0 to the sensor with I2C:
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.
Here's the Raspberry Pi wired with I2C:
CircuitPython Installation of MPRLS Library
You'll need to install the Adafruit CircuitPython MPRLS 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 CircuitPython starter guide has a great page on how to install the library bundle.
For non-express boards like the Trinket M0 or Gemma M0, you'll need to manually install the necessary libraries from the bundle:
- adafruit_mprls.mpy
- adafruit_bus_device
Before continuing make sure your board's lib folder or root filesystem has the adafruit_mprls.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.
Python Installation of MPRLS Library
You'll need to install the Adafruit_Blinka library that provides the CircuitPython support in Python. This may also require enabling I2C on your platform and verifying you are running Python 3. Since each platform is a little different, and Linux changes often, please visit the CircuitPython on Linux guide to get your computer ready!
Once that's done, from your command line run the following command:
sudo pip3 install adafruit-circuitpython-mprls
If your default Python is version 3 you may need to run 'pip' instead. Just make sure you aren't trying to use CircuitPython on Python 2.x, it isn't supported!
CircuitPython & Python Usage
To demonstrate the usage of the sensor we'll initialize it and read the pressure from the board's Python REPL.
Since you're using an I2C connection run the following code to import the necessary modules and initialize the I2C connection with the sensor:
import time import board import busio import adafruit_mprls i2c = busio.I2C(board.SCL, board.SDA) mpr = adafruit_mprls.MPRLS(i2c, psi_min=0, psi_max=25)
Now you're ready to read values from the sensor using any of these properties:
- pressure - The measured pressure, in hPa.
For example to print the pressure:
print("Pressure (hPa):", mpr.pressure)
That's all there is to using the MPRLS sensor with CircuitPython!
# SPDX-FileCopyrightText: 2021 ladyada for Adafruit Industries
# SPDX-License-Identifier: MIT
import time
import board
import adafruit_mprls
i2c = board.I2C() # uses board.SCL and board.SDA
# i2c = board.STEMMA_I2C() # For using the built-in STEMMA QT connector on a microcontroller
# Simplest use, connect to default over I2C
mpr = adafruit_mprls.MPRLS(i2c, psi_min=0, psi_max=25)
# You can also specify both reset and eoc pins
"""
import digitalio
reset = digitalio.DigitalInOut(board.D5)
eoc = digitalio.DigitalInOut(board.D6)
mpr = adafruit_mprls.MPRLS(i2c, eoc_pin=eoc, reset_pin=reset,
psi_min=0, psi_max=25)
"""
while True:
print((mpr.pressure,))
time.sleep(1)
