Introduction

A CircuitPython driver for the Sensirion SGP30 gas sensor with eCO2 and TVOC output. This sensor uses I2C!

Installation and Dependencies

This driver depends on:

• Adafruit CircuitPython
• Bus Device

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-sgp30

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

sudo pip3 install adafruit-circuitpython-sgp30

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-sgp30

Usage Notes

See the guide for wiring and installation instructions.

First, import the library:

import busio
import adafruit_sgp30

Next, initialize the I2C bus object:

import board
i2c_bus = busio.I2C(board.SCL, board.SDA, frequency=100000)

Since we have the I2C bus object, we can now use it to instantiate the SGP30 object:

sgp30 = adafruit_sgp30.Adafruit_SGP30(i2c_bus)

Reading from the Sensor

To read from the sensor:

eCO2, TVOC = sgp30.iaq_measure()
print("eCO2 = %d ppm \t TVOC = %d ppb" % (eCO2, TVOC))

Contributing

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

Building locally

To build this library locally you'll need to install the circuitpython-build-tools package.

python3 -m venv .env
source .env/bin/activate
pip install circuitpython-build-tools

Once installed, make sure you are in the virtual environment:

source .env/bin/activate

Then run the build:

circuitpython-build-bundles --filename_prefix adafruit-circuitpython-sgp30 --library_location .

Sphinx documentation

Sphinx is used to build the documentation based on rST files and comments in the code. First, install dependencies (feel free to reuse the virtual environment from above):

python3 -m venv .env
source .env/bin/activate
pip install Sphinx sphinx-rtd-theme

Now, once you have the virtual environment activated:

cd docs
sphinx-build -E -W -b html . _build/html

This will output the documentation to docs/_build/html. Open the index.html in your browser to view them. It will also (due to -W) error out on any warning like Travis will. This is a good way to locally verify it will pass.