Temperature Sensor Monitor

Used for a Rashberry PI sensor. The goal is to setup a simple program that polls a sensor installed on a rasberry Pi

Steps

This assumes the following

• Rasbian is installed on the Raspberry Pi
• Adafruit AM2302 (wired DHT22) temperature-humidity sensor (ADA393) is installed on pin 18
• A mongoDB instance is setup

1. Install Python 2.6/2.7
   • sudo apt-get update
   • sudo apt-get install build-essential python-dev
   • sudo apt-get install python-pip
2. Install Adafruit Python DHT Sensor Library
   • pip install Adafruit_Python_DHT
3. Install PyMongo
   • pip install pymongo
4. Set up dbconfig.py

   • variable name	Purpose	Notes
     MONGO_DB_HOST	URL of host
     MONGO_DB_PORT	Mongo DB Port
     MONGO_DB_NAME	Mongo DB Name
     MONGO_DB_USER_NAME	Mongo UN
     MONGO_DB_PASSWORD	Mongo Password
     MONGO_DB_STATS_COLLECTION	Mongo Collection Name
     SENSOR_LOCATION	Location Of the Sensor	Ex: Basement

5. Setup cron job to run sensor
   • Edit current Cron jobs
     • sudo crontab -e
   • Set Polling time
     • Note the polling time should not be faster then every 2 seconds
     • This example conjob does it every 5 mins
       • */5 * * * * sudo python /home/pi/temperatureHumidSensor/sensorPoll.py

Sources

1. Adafruit Python DHT Github page
2. Rethinking temperature, sensors, and Raspberry Pi
3. PyMongo Tutorial
4. Adafruit AM2302 (WIRED DHT22) TEMPERATURE-HUMIDITY SENSOR page