It's easy to use the BME680 sensor with Python and CircuitPython, and the Adafruit CircuitPython BME680 module. This module allows you to easily write Python code that reads the humidity, temperature, pressure, and more 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 a BME680 to your board exactly as shown on the previous pages for Arduino. Here's an example of wiring a Feather M0 to the sensor with I2C:
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Board 3V to sensor VIN (red wire on STEMMA QT version)
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Board GND to sensor GND (black wire on STEMMA QT version)
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Board SCL to sensor SCK (yellow wire on STEMMA QT version)
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Board SDA to sensor SDI (blue wire on STEMMA QT version)
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:
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Pi 3V3 to sensor VIN (red wire on STEMMA QT version)
- Pi GND to sensor GND (black wire on STEMMA QT version)
- Pi SCL to sensor SCK (yellow wire on STEMMA QT version)
- Pi SDA to sensor SDI (blue wire on STEMMA QT version)
CircuitPython Installation of BME680 Library
Next you'll need to install the Adafruit CircuitPython BME680 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 introduction guide has a great page on how to install the library bundle for both express and non-express boards.
Remember for non-express boards like the, you'll need to manually install the necessary libraries from the bundle:
- adafruit_bme680.mpy
- adafruit_bus_device
You can also download the adafruit_bme680.mpy from its releases page on Github.
Before continuing make sure your board's lib folder or root filesystem has the adafruit_bme680.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 BME680 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-bme680
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 temperature, humidity, and more from the board's Python REPL.
Run the following code to import the necessary modules and initialize the I2C connection with the sensor:
import board import adafruit_bme680 i2c = board.I2C() sensor = adafruit_bme680.Adafruit_BME680_I2C(i2c)
Now you're ready to read values from the sensor using any of these properties:
- temperature - The sensor temperature in degrees Celsius.
- gas - The resistance (in Ohms) of the gas sensor. This is proportional to the amount of VOC particles in the air.
- humidity - The percent humidity as a value from 0 to 100%.
- pressure - The pressure in hPa.
- altitude - The altitude in meters.
print('Temperature: {} degrees C'.format(sensor.temperature))
print('Gas: {} ohms'.format(sensor.gas))
print('Humidity: {}%'.format(sensor.humidity))
print('Pressure: {}hPa'.format(sensor.pressure))
For altitude you'll want to set the pressure at sea level for your location to get the most accurate measure (remember these sensors can only infer altitude based on pressure and need a set calibration point). Look at your local weather report for a pressure at sea level reading and set the seaLevelhPA property:
sensor.seaLevelhPa = 1014.5
Then read the altitude property for a more accurate altitude reading (but remember this altitude will fluctuate based on atmospheric pressure changes!):
print('Altitude: {} meters'.format(sensor.altitude))
That's all there is to using the BME680 sensor with CircuitPython!
# SPDX-FileCopyrightText: 2021 ladyada for Adafruit Industries
# SPDX-License-Identifier: MIT
import time
import board
import adafruit_bme680
# Create sensor object, communicating over the board's default I2C bus
i2c = board.I2C() # uses board.SCL and board.SDA
# i2c = board.STEMMA_I2C() # For using the built-in STEMMA QT connector on a microcontroller
bme680 = adafruit_bme680.Adafruit_BME680_I2C(i2c, debug=False)
# change this to match the location's pressure (hPa) at sea level
bme680.sea_level_pressure = 1013.25
# You will usually have to add an offset to account for the temperature of
# the sensor. This is usually around 5 degrees but varies by use. Use a
# separate temperature sensor to calibrate this one.
temperature_offset = -5
while True:
print("\nTemperature: %0.1f C" % (bme680.temperature + temperature_offset))
print("Gas: %d ohm" % bme680.gas)
print("Humidity: %0.1f %%" % bme680.relative_humidity)
print("Pressure: %0.3f hPa" % bme680.pressure)
print("Altitude = %0.2f meters" % bme680.altitude)
time.sleep(1)
