.. image:: https://readthedocs.org/projects/adafruit-circuitpython-dht/badge/?version=latest :target: https://docs.circuitpython.org/projects/dht/en/latest/ :alt: Documentation Status
.. image:: https://raw.githubusercontent.com/adafruit/Adafruit_CircuitPython_Bundle/main/badges/adafruit_discord.svg :target: https://adafru.it/discord :alt: Discord
.. image:: https://github.com/adafruit/Adafruit_CircuitPython_DHT/workflows/Build%20CI/badge.svg :target: https://github.com/adafruit/Adafruit_CircuitPython_DHT/actions :alt: Build Status
.. image:: https://img.shields.io/badge/code%20style-black-000000.svg :target: https://github.com/psf/black :alt: Code Style: Black
CircuitPython support for the DHT11 and DHT22 temperature and humidity devices.
This driver depends on:
Adafruit CircuitPython <https://github.com/adafruit/circuitpython>
_Please ensure all dependencies are available on the CircuitPython filesystem.
This is easily achieved by downloading
the Adafruit library and driver bundle <https://github.com/adafruit/Adafruit_CircuitPython_Bundle>
_.
.. note::
This library uses the pulseio
module in CircuitPython. As of CircuitPython 7.0.0, pulseio
is
no longer available on the smallest CircuitPython builds,
such as the Trinket M0, Gemma M0, and Feather M0 Basic boards.
You can substitute a more modern sensor, which will work better as well.
See the guide Modern Replacements for DHT11 and DHT22 Sensors <https://learn.adafruit.com/modern-replacements-for-dht11-dht22-sensors>
_
for suggestions.
On supported GNU/Linux systems like the Raspberry Pi, you can install the driver locally from PyPI <https://pypi.org/project/adafruit-circuitpython-dht/>
_. To install for current user:
.. code-block:: shell
pip3 install adafruit-circuitpython-dht
To install system-wide (this may be required in some cases):
.. code-block:: shell
sudo pip3 install adafruit-circuitpython-dht
To install in a virtual environment in your current project:
.. code-block:: shell
mkdir project-name && cd project-name
python3 -m venv .venv
source .venv/bin/activate
pip3 install adafruit-circuitpython-dht
Designed specifically to work with the Adafruit DHT series sensors:
DHT22 temperature-humidity sensor + extras <https://www.adafruit.com/products/385>
_DHT11 temperature-humidity sensor + extras <https://www.adafruit.com/products/386>
_.. note:: DHT11 and DHT22 devices both need a pull-resistor on the data signal wire. This resistor is in the range of 1k to 5k
gpio
group... note::
Using a more modern sensor will avoid these issues.
See the guide Modern Replacements for DHT11 and DHT22 Sensors <https://learn.adafruit.com/modern-replacements-for-dht11-dht22-sensors>
_.
Of course, you must import the library to use it:
.. code:: python
import adafruit_dht
The DHT type devices use single data wire, so import the board pin
.. code:: python
from board import <pin>
Now, to initialize the DHT11 device:
.. code:: python
dht_device = adafruit_dht.DHT11(<pin>)
OR initialize the DHT22 device:
.. code:: python
dht_device = adafruit_dht.DHT22(<pin>)
Now get the temperature and humidity values
.. code:: python
temperature = dht_device.temperature
humidity = dht_device.humidity
These properties may raise an exception if a problem occurs. You should use try/raise logic and catch RuntimeError and then retry getting the values after at least 2 seconds. If you try again to get a result within 2 seconds, cached values are returned.
API documentation for this library can be found on Read the Docs <https://docs.circuitpython.org/projects/dht/en/latest/>
_.
For information on building library documentation, please check out this guide <https://learn.adafruit.com/creating-and-sharing-a-circuitpython-library/sharing-our-docs-on-readthedocs#sphinx-5-1>
_.
Contributions are welcome! Please read our Code of Conduct <https://github.com/adafruit/Adafruit_CircuitPython_DHT/blob/main/CODE_OF_CONDUCT.md>
_
before contributing to help this project stay welcoming.