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Driver for Sensirion SCD4X CO2 sensor


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 or individual libraries can be installed using circup.

Purchase one from the Adafruit shop

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-scd4x

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

sudo pip3 install adafruit-circuitpython-scd4x

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-scd4x

Installing to a Connected CircuitPython Device with Circup

Make sure that you have circup installed in your Python environment. Install it with the following command if necessary:

pip3 install circup

With circup installed and your CircuitPython device connected use the following command to install:

circup install scd4x

Or the following command to update an existing version:

circup update

Usage Example

import time
import board
import adafruit_scd4x

i2c = board.I2C()
scd4x = adafruit_scd4x.SCD4X(i2c)
print("Serial number:", [hex(i) for i in scd4x.serial_number])

print("Waiting for first measurement....")

while True:
    if scd4x.data_ready:
        print("CO2: %d ppm" % scd4x.CO2)
        print("Temperature: %0.1f *C" % scd4x.temperature)
        print("Humidity: %0.1f %%" % scd4x.relative_humidity)


API documentation for this library can be found on Read the Docs.


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


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

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