Python & CircuitPython

It's easy to use the TCS34725 sensor with Python and CircuitPython, and the Adafruit CircuitPython TCS34725 module.  This module allows you to easily write Python code that reads the color 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 TCS34725 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 an I2C connection:

  • 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 TCS34725 Library

You'll need to install the Adafruit CircuitPython TCS34725 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_tcs34725.mpy
  • adafruit_bus_device

Before continuing make sure your board's lib folder or root filesystem has the adafruit_tcs34725.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 TCS34725 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-tcs34725

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 color 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 busio
import adafruit_tcs34725
i2c = busio.I2C(board.SCL, board.SDA)
sensor = adafruit_tcs34725.TCS34725(i2c)

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

  • color_rgb_bytes - A 3-tuple of the red, green, blue color values.  These are returned as bytes from 0 to 255 (0 is low intensity, 255 is maximum intensity).
  • temperature - The color temperature in Kelvin detected by the sensor.  This is computed from the color and might not be super accurate!
  • lux - The light intensity in lux detected by the sensor.  This is computed from the color and might not be super accurate!
print('Color: ({0}, {1}, {2})'.format(*sensor.color_rgb_bytes))
print('Temperature: {0}K'.format(sensor.temperature))
print('Lux: {0}'.format(sensor.lux))

In addition there are some properties you can both read and write to change how the sensor behaves:

  • integration_time - The integration time of the sensor in milliseconds.  Must be a value between 2.4 and 614.4.
  • gain - The gain of the sensor, must be a value of 1, 4, 16, 60.
sensor.integration_time = 200
sensor.gain = 60

See the simpletest.py example for a complete demo of printing the range every second.  Save this as code.py on the board and examine the REPL output to see the range printed every second.

That's all there is to using the TCS34725 with CircuitPython!

Full Example Code

# Simple demo of the TCS34725 color sensor.
# Will detect the color from the sensor and print it out every second.
import time

import board
import busio

import adafruit_tcs34725


# Initialize I2C bus and sensor.
i2c = busio.I2C(board.SCL, board.SDA)
sensor = adafruit_tcs34725.TCS34725(i2c)

# Main loop reading color and printing it every second.
while True:
    # Read the color as RGB bytes (0-255 values).
    r, g, b = sensor.color_rgb_bytes
    print('Detected color: #{0:02X}{1:02X}{2:02X}'.format(r, g, b))
    # Read the color temperature and lux of the sensor too.
    try:
        temp = sensor.temperature
        lux = sensor.lux
        print('Temperature: {0}K Lux: {1}'.format(temp, lux))
    except ZeroDivisionError:
        print("No light to measure")
    # Delay for a second and repeat.
    time.sleep(1.0)
This guide was first published on May 21, 2013. It was last updated on Oct 19, 2018. This page (Python & CircuitPython) was last updated on Aug 14, 2018.