ESP8266-based Air Quality Monitor

This is source code of the firmware for the air quality / weather station I've built. The station measures PM1, PM2.5 and PM10 particulate matter levels and humidity and temperature. The software runs on ESP8266. I use WeMoS D1 Mini for easy programming through USB.

Features

• Connects to local Wifi to get on the Internet.
• Automatically synchronizes with Internet time using NTP.
• Reads temperature and humidity from a DHT22 sensor (can be easily modified to work with DHT11).
• Reads particulate matter levels from Plantower PMS7003 laser sensor.
• Displays air parameters on a 4x20 LCD screen attached using I²C bus.
• Supports LCD screen dimming through PWM control.
• Stores sensor readouts in internal flash (1 MB of free space).
• Runs a tiny webserver and displays air parameters on a minimalistic, responsive website.
• Presents graphs with air quality history in the browser, using Javascript and a bit of REST.
• Can optionally read remote data (e.g. outside temperature) from RF-433 radio receiver (unfinished).
• New! Uploads sensor readouts to DataStax Astra!

Installation

• Install VSCode.
• Install PlatformIO plugin.
• Checkout this project from GitHub and open with PlatformIO.
• Create data/secret/wifi.txt file and put you network SSID in the first line and your wifi password in the second line.
• Optionally create data/secret/astra.txt file with your DataStax astra access information in 4 lines of text:
  1. database UUID
  2. database region
  3. username (account id)
  4. password (access token)
• Connect WeMos Mini D1 to USB.
• Hit Ctrl+Shift+P, select "PlatformIO: Upload" and wait a few seconds.
• Run pio run -t uploadfs to flash the UI files and credentials.
• If something goes wrong, open Serial Monitor and read debugging information sent there.