The SparkFun Qwiic CO2, Temperaure, and Humidity SCD4X Module provides a simple and cost effective solution for adding CO2, Temperaure, and Humidity capabilities to your project. Implementing a SparkFun Qwiic I2C interface, these sensors can be rapidly added to any project with boards that are part of the SparkFun Qwiic ecosystem.
This repository implements a Python package for the SparkFun Qwiic SCD4X. This package works with Python, MicroPython and CircuitPython.
This python package enables the user to access the features of the SCD4X via a single Qwiic cable. This includes reading CO2, reading temperature, reading humidity and more. The capabilities of the SCD4X are each demonstrated in the included examples.
New to qwiic? Take a look at the entire SparkFun qwiic ecosystem.
This Python package supports the following SparkFun qwiic products on Python, MicroPython and Circuit python.
| Python | Platform | Boards |
|---|---|---|
| Python | Linux | Raspberry Pi , NVIDIA Jetson Orin Nano via the SparkFun Qwiic SHIM |
| MicroPython | Raspberry Pi - RP2, ESP32 | SparkFun Pro Micro RP2350, SparkFun IoT RedBoard ESP32, SparkFun IoT RedBoard RP2350 |
| CircuitPython | Raspberry Pi - RP2, ESP32 | SparkFun Pro Micro RP2350, SparkFun IoT RedBoard ESP32, SparkFun IoT RedBoard RP2350 |
Note
The listed supported platforms and boards are the primary platform targets tested. It is fully expected that this package will work across a wide variety of Python enabled systems.
The first step to using this package is installing it on your system. The install method depends on the python platform. The following sections outline installation on Python, MicroPython and CircuitPython.
The package is primarily installed using the pip3 command, downloading the package from the Python Index - "PyPi".
Note - the below instructions outline installation on a Linux-based (Raspberry Pi) system.
First, setup a virtual environment from a specific directory using venv:
python3 -m venv path/to/venvYou can pass any path as path/to/venv, just make sure you use the same one for all future steps. For more information on venv click here.
Next, install the qwiic package with:
path/to/venv/bin/pip3 install sparkfun-qwiic-scd4xNow you should be able to run any example or custom python scripts that have import qwiic_scd4x by running e.g.:
path/to/venv/bin/python3 example_script.pyIf not already installed, follow the instructions here to install mpremote on your computer.
Connect a device with MicroPython installed to your computer and then install the package directly to your device with mpremote mip.
mpremote mip install github:sparkfun/qwiic_scd4x_pyIf you would also like to install the examples for this repository, issue the following mip command as well:
mpremote mip install --target "" github:sparkfun/qwiic_scd4x_py@examplesIf not already installed, follow the instructions here to install CircUp on your computer.
Ensure that you have the latest version of the SparkFun Qwiic CircuitPython bundle.
circup bundle-add sparkfun/Qwiic_PyFinally, connect a device with CircuitPython installed to your computer and then install the package directly to your device with circup.
circup install --py qwiic_scd4xIf you would like to install any of the examples from this repository, issue the corresponding circup command from below. (NOTE: The below syntax assumes you are using CircUp on Windows. Linux and Mac will have different path seperators. See the CircUp "example" command documentation for more information)
circup example qwiic_scd4x\qwiic_scd4x_ex1_basic
circup example qwiic_scd4x\qwiic_scd4x_ex2_low_power
circup example qwiic_scd4x\qwiic_scd4x_ex3_disable_auto_calibration
circup example qwiic_scd4x\qwiic_scd4x_ex4_skip_stop_periodic
circup example qwiic_scd4x\qwiic_scd4x_ex6_signal_compensation
circup example qwiic_scd4x\qwiic_scd4x_ex7_test_and_reset
circup example qwiic_scd4x\qwiic_scd4x_ex8_scd41_single_shot
circup example qwiic_scd4x\qwiic_scd4x_ex9_sensor_type
Below is a quickstart program to print readings from the SCD4X.
See the examples directory for more detailed use examples and examples/README.md for a summary of the available examples.
import qwiic_scd4x
import sys
import time
def runExample():
print("\nQwiic SCD4x Example 1 - Basic Readings\n")
mySCD4x = qwiic_scd4x.QwiicSCD4x()
if mySCD4x.is_connected() == False:
print("The device isn't connected to the system. Please check your connection", file=sys.stderr)
return
if mySCD4x.begin() == False:
print("Error while initializing device", file=sys.stderr)
return
while True:
if mySCD4x.read_measurement(): # This must be called to get new data. It will return false until new data is available
print("\nCO2(ppm):", mySCD4x.get_co2())
print("Temperature(C):", mySCD4x.get_temperature())
print("Humidity(%RH):", mySCD4x.get_humidity())
else:
print(".", end="")
time.sleep(0.5) # Only check for new data every 0.5 seconds
if __name__ == '__main__':
try:
runExample()
except (KeyboardInterrupt, SystemExit) as exErr:
print("\nEnding Example")
sys.exit(0)
