The Arduino library was recently updated to include a new RGB to CCT algorithm based on the DN40 app note from Taos (now AMS): adafruit/Adafruit_TCS34725@116a9aa

This function should also be implemented here since it's far more accurate that the current color temperature algorithm.

Add a Basic DisplayIO Based Example

We would like to have a basic displayio example for this library. The example should be written for microcontrollers with a built-in display. At a minimum it should show a Label on the display and update it with live readings from the sensor.

The example should not be overly complex, it's intended to be a good starting point for displayio based projects that utilize this sensor library. Try to keep all visual content as near to the top left corner as possible in order to best fascilitate devices with small built-in display resolutions.

The new example should follow the naming convention examples/libraryname_displayio_simpletest.py with "libraryname" being replaced by the actual name of this library.

You can find an example of a Pull Request that adds this kind of example here: adafruit/Adafruit_CircuitPython_BME680#72

We have a guide that covers the process of contributing with git and github: https://learn.adafruit.com/contribute-to-circuitpython-with-git-and-github

If you're interested in contributing but need additional help, or just want to say hi, feel free to join the Discord server to ask questions: https://adafru.it/discord

There are missing type annotations for some functions in this library.

The typing module does not exist on CircuitPython devices so the import needs to be wrapped in try/except to catch the error for missing import. There is an example of how that is done here:

try:
    from typing import List, Tuple
except ImportError:
    pass

Once imported the typing annotations for the argument type(s), and return type(s) can be added to the function signature. Here is an example of a function that has had this done already:

def wrap_text_to_pixels(
    string: str, max_width: int, font=None, indent0: str = "", indent1: str = ""
) -> List[str]:

If you are new to Git or Github we have a guide about contributing to our projects here: https://learn.adafruit.com/contribute-to-circuitpython-with-git-and-github

There is also a guide that covers our CI utilities and how to run them locally to ensure they will pass in Github Actions here: https://learn.adafruit.com/creating-and-sharing-a-circuitpython-library/check-your-code In particular the pages: Sharing docs on ReadTheDocs and Check your code with pre-commit contain the tools to install and commands to run locally to run the checks.

If you are attempting to resolve this issue and need help, you can post a comment on this issue and tag both @FoamyGuy and @kattni or reach out to us on Discord: https://adafru.it/discord in the #circuitpython-dev channel.

The following locations are reported by mypy to be missing type annotations:

• adafruit_tcs34725.py:110
• adafruit_tcs34725.py:176
• adafruit_tcs34725.py:195
• adafruit_tcs34725.py:220
• adafruit_tcs34725.py:235
• adafruit_tcs34725.py:272
• adafruit_tcs34725.py:292
• adafruit_tcs34725.py:303
• adafruit_tcs34725.py:370
• adafruit_tcs34725.py:379
• adafruit_tcs34725.py:386
• adafruit_tcs34725.py:393
• adafruit_tcs34725.py:400

The current implementation of color is in need of replacement. See discussions in #14 and #10 .

Both sensor.color_temperature and sensor.lux throw division by zero errors:

Traceback (most recent call last):
File "code.py", line 7, in
File "adafruit_tcs34725.py", line 113, in color_temperature
File "adafruit_tcs34725.py", line 314, in _temperature_and_lux_dn40
ZeroDivisionError: division by zero

Here is my code:

from board import SCL, SDA
from busio import I2C
from adafruit_tcs34725 import TCS34725
i2c = I2C(SCL, SDA)
sensor = TCS34725(i2c)
print('Color: ({0}, {1}, {2})'.format(*sensor.color_rgb_bytes))
print('Temperature: {0}K'.format(sensor.color_temperature))
print('Lux: {0}'.format(sensor.lux))

I think it may be caused when the color source is too bright.

Also there is a typo on the Adafruit tutorial. The property temperature should be color_temperature. It is incorrect in the docs and the example: https://learn.adafruit.com/adafruit-color-sensors/python-circuitpython#circuitpython-and-python-usage-3-7

Doc string claims the return should be 3-tuple with range 0-255. But it's possible to get values greater than this.

Adafruit CircuitPython 3.0.0 on 2018-07-09; Adafruit CircuitPlayground Express with Crickit libraries with samd21g18
>>> import board, busio
>>> import adafruit_tcs34725
>>> i2c = busio.I2C(board.SCL, board.SDA)
>>> sensor = adafruit_tcs34725.TCS34725(i2c)
>>> sensor.integration_time
2.4
>>> sensor.gain
1
>>> sensor.color_rgb_bytes
(18, 25, 9)
>>> sensor.integration_time = 50
>>> sensor.integration_time
48.0
>>> sensor.color_rgb_bytes
(2, 554, 570)
>>> 

I am using the RGB sensor in a project. There I have made the experience that the sensor shows really strange behaviour for larger value. So at small value the sensor shows the behaviour that is excpected but for large value, so for exemple then the roomlight is on, the sensor starts to jump around 2 different levels. I have ploted the values in the two plots below. What could be the problem ? I am using a gain of 4 and an integration time of 50ms. I have tried to change the integration time but it didn't help.

The experimental setup is:

Change the assert checks to raise an appropriate Error along with helpful message.

On /usr/local/lib/python3.5/dist-packages/adafruit_tcs34725.py the function def color_rgb_bytes(self) should check if rgb values are greater than zero to avoid the division by zero exception

File "/usr/local/lib/python3.5/dist-packages/adafruit_tcs34725.py", line 240, in color_rgb_bytes
red = int(pow((int((r/clear) * 256) / 255), 2.5) * 255)
ZeroDivisionError: division by zero

The sensor returns values regardless of setting of active. What is it really doing?

Adafruit CircuitPython 3.0.0 on 2018-07-09; Adafruit CircuitPlayground Express with Crickit libraries with samd21g18
>>> import board, busio
>>> import adafruit_tcs34725
>>> i2c = busio.I2C(board.SCL, board.SDA)
>>> sensor = adafruit_tcs34725.TCS34725(i2c)
>>> sensor.active
False
>>> sensor.color_rgb_bytes
(17, 25, 9)
>>> sensor.active
False
>>> sensor.active = True
>>> sensor.color_rgb_bytes
(17, 25, 9)
>>> sensor.active
True
>>> 

See if @all-iver's work here:

adafruit/Adafruit_Python_TCS34725#2

...is something that should be ported across to this library.

When acquiring data sometimes the response time is twice as long as expected. For integration times >90ms it takes ~95ms for the TCS34725 to respond, and expected. For <90ms it takes twice as long (say, 186ms for integration time of 80ms).

This affects situations in a continuous loop, since for integration times < 90ms will have ~50% "sensing" rate. I've wrestled with the problem for a while. It seems to be less of an issue in M4 and in the latest TCS34725 driver (v3.3.3). In M0 and older drivers the issue persisted through all of integration times.

I used the code below for testing

import time
import board
import adafruit_tcs34725
sensorRGB = adafruit_tcs34725.TCS34725(board.I2C())
sensorRGB.integration_time = 90#for integration time 2.4 - 614.4 ms
while True:
tic = time.monotonic()
print(sensorRGB.color_raw)
print(time.monotonic()-tic)

When the LED is turned off and a white paper is placed very close to the sensor, the color is pure white so it causes a divide by zero error. I have a kind-of fix to this that makes it not have an error when the color is white but doesn't give a very accurate color temperature.

Add a color property that complies with design guide.