Python & CircuitPython

It's easy to use the VEML6075 sensor with Python or CircuitPython and the Adafruit CircuitPython VEML6075 module.  This module allows you to easily write Python code that reads the UV index 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 VEML6075 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:

  • Board 3V to sensor VIN
  • Board GND to sensor GND
  • Board SCL to sensor SCL
  • Board SDA to sensor SDA

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:

  • Pi 3V3 to sensor VIN
  • Pi GND to sensor GND
  • Pi SCL to sensor SCL
  • Pi SDA to sensor SDA

CircuitPython Installation of VEML6075 Library

You'll need to install the Adafruit CircuitPython VEML6075 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_veml6075.mpy
  • adafruit_bus_device

Before continuing make sure your board's lib folder or root filesystem has the adafruit_veml6075.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 VEML6075 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-veml6075

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 UV index 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:

Download: file
import time
import board
import busio
import adafruit_veml6075
i2c = busio.I2C(board.SCL, board.SDA)
veml = adafruit_veml6075.VEML6075(i2c, integration_time=100)

The integration_time is the amount of time the VEML6075 is sampling data for, in milliseconds. Valid times are 50, 100, 200, 400 or 800ms. We've chosen to set it to 100 milliseconds.

Now you're ready to read values from the sensor using any of these properties:

  • uv_index - The calculated UV Index.
  • uva - The calibrated UVA reading, in 'counts' over the sample period
  • uvb - The calibrated UVB reading, in 'counts' over the sample period

For example to print the UV index:

Download: file
print("UV index:", veml.uv_index)
Indoors you will get very low or even negative UV index values! Take your sensor outside into the sun, or use a solar lamp

That's all there is to using the VEML6075 sensor with CircuitPython!

Full Example Code

import time
import board
import busio
import adafruit_veml6075

i2c = busio.I2C(board.SCL, board.SDA)

veml = adafruit_veml6075.VEML6075(i2c, integration_time=100)

print("Integration time: %d ms" % veml.integration_time)

while True:
    print(veml.uv_index)
    time.sleep(1)
This guide was first published on Sep 26, 2018. It was last updated on Sep 26, 2018. This page (Python & CircuitPython) was last updated on May 27, 2019.