weather-monitor

Introduction

A weather monitor using a Raspberry Pi, BMP085 and DHT22 sensor, uploading to IoT platform ThingSpeak and Slack using their web apis. https://au.mathworks.com/help/thingspeak/update-a-channel.html https://github.com/raddevon/pyspeak

Todo

After you've got it working you could set the filesystem to read only to save SD card wear (https://hallard.me/raspberry-pi-read-only/, or like me just disable swap and log to RAM: http://raspberrypi.stackexchange.com/questions/169/how-can-i-extend-the-life-of-my-sd-card)
Incorporate Shinyei PPD42NS air quality into IoT platform

Hardware

Tested on: Rapsberry Pi Model A (original)
Adafruit BMP085 temp and pressure sensor

VCC -> 3.3v
GND -> GND
SCL -> GPIO 03
SDA -> GPIO 02

DHT22 temp and humidity sensor pin 1 / GND must have a voltage divider to reduce 5v to 3.3v

pin 1 -> 3.3v
pin 2 -> GPIO 08 (inside sensor connected to GPIO07)
pin 3 -> NONE
pin 4 => GND

Shinyei PPD42NS particle sensor pin 1 / GND must have a voltage divider to reduce 5v to 3.3v

pin + -> 3.3v
pin 2 -> GPIO 07
pin - -> GND

Accounts

You'll need a thingspeak account, and to create a channel with three fields, and get your API key You'll need a slack account, and to get your API key

Installation

Starting with Raspbian Jessie Lite, update the system:

sudo apt-get update
sudo apt-get install python-dev python-pip git

Enable i2c by: sudo raspi-config and Interface Options > I2C > Enable And whilst you're in the config program, change your timezone Exit and reboot
Clone this repo and the BMP085 repo:

git clone https://github.com/andy-pi/weather-monitor.git
git clone https://github.com/adafruit/Adafruit_Python_BMP.git
cd Adafruit_Python_BMP
sudo python setup.py install

Install PIGPIO, a library for low level GPIO operations (this repo includes DHT22.py) (http://abyz.co.uk/rpi/pigpio/)

wget abyz.co.uk/rpi/pigpio/pigpio.zip
unzip pigpio.zip
cd PIGPIO
make
sudo make install

Install Python Slack Api wrapper:

sudo pip install slacker

Update root crontab with the following lines to run the thingspeak script every 15 mins and slack update daily:

@reboot /usr/local/bin/pigpiod
@reboot sntp -s 24.56.178.140 # to force time update on reboot
0,15,30,45 * * * * python /home/pi/weather-monitor/thingspeak_update.py # for logging add >> /home/pi/weather-monitor/log 2>&1
30 6 * * * python /home/pi/weather-monitor/slack_update.py

Air Quality - Shinyei PPD42NS only

Basic Printout of air quality

Carry out steps 1-4 above and then:

sudo pigpiod
python air_quality.py

The output will be printed on screen. Note that the instantaneous AQI is not actually correct, it should be taken as a 24 average of the PM2.5 particles in micrograms/m3

phaseOne/weather-monitor