RPi-IoT

A collection of RPi projects

Reading Data from a DHT11 Sensor

Setup the Raspberry Pi

Install the Raspbian OS. Using the OS without the Desktop version appears to be more stable than the version with Desktop. Connect the DHT11 sensor data pin to the pin specified in the DHT11_PIN (24). The + pin to 3.3v and - pin to a ground pin on the Raspberry Pi.

Configuration

Streaming data to Initial State or Logstash are option. To enable either one, simply define their environment variables. The .env file is supported by the python-dotenv module.

Stream data to InitialState

• IS_BUCKET_NAME=[the IS bucket name]
• IS_BUCKET_KEY=[the IS bucket key]
• IS_ACCESS_KEY=[the IS access key]

Stream data to Logstash

• LOGSTASH_HOSTS=[the list of LogStash hosts]

Example:
LOGSTASH_HOSTS="127.0.0.1:8080,127.0.0.2:8080"

Update OS and install tools

sudo apt-get update && sudo apt-get upgrade
sudo apt-get install -y git python3-pip screen

Reading data

git clone https://github.com/htquach/RPi-IoT
cd RPi-IoT/
pip3 install -r requirements.txt -r requirements_raspi.txt
screen -S RPi-IoT python3 sensor_dht11.py

Install sensor_dht11.py as a service

Run the following commands as root sudo -i

cp sensor_dht11.service /etc/systemd/system/
systemctl daemon-reload
systemctl start sensor_dht11.service
systemctl status sensor_dht11.service
systemctl enable sensor_dht11.service