CircuitPython support for the DHT11 and DHT22 temperature and humidity devices.
This driver depends on:
Please ensure all dependencies are available on the CircuitPython filesystem. This is easily achieved by downloading the Adafruit library and driver bundle.
Installing from PyPI¶
On supported GNU/Linux systems like the Raspberry Pi, you can install the driver locally from PyPI. To install for current user:
pip3 install adafruit-circuitpython-dht
To install system-wide (this may be required in some cases):
sudo pip3 install adafruit-circuitpython-dht
To install in a virtual environment in your current project:
mkdir project-name && cd project-name python3 -m venv .env source .env/bin/activate pip3 install adafruit-circuitpython-dht
The DHT11 and DHT22 devices both need a pull-resistor on the data signal wire. This resistor is in the range of 1k to 5k. Please check your device datasheet for the appropriate value.
Of course, you must import the library to use it:
The DHT type devices use single data wire, so import the board pin
from board import <pin>
Now, to initialize the DHT11 device:
dht_device = adafruit_dht.DHT11(<pin>)
OR initialize the DHT22 device:
dht_device = adafruit_dht.DHT22(<pin>)
Read temperature and humidity¶
Now get the temperature and humidity values
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.
Contributions are welcome! Please read our Code of Conduct before contributing to help this project stay welcoming.