DHT12 Connection Diagram:-

Dependencies:-

1. Firmata library for Python Pymata

   pip install pymata
   

2. MQTT Client Library for Python Eclipse Paho

   pip install paho-mqtt
   

Run on Boot:-

To make the Python script run on boot I have used InitScripts, to creare the job follow the following commands, (Its a basic script and doesnot have error handling and all)

vi /etc/init.d/dht12

Paste the followinf content,

#!/bin/sh /etc/rc.common

START=98

start(){
        ubus  -t 60 wait_for network.interface network.interface.loopback # Makes sure network is up
        echo "Starting the DHT12 Sensor Script"
        python /root/sensor.py &
}

Make the file executable and enable it,

chmod +x /etc/init.d/dht12
/etc/init.d/dht12 enable

Now you can reboot the module and can see the sensor data getting published to the provided topic.