balsama / picotemps

Grabs temps from a network of Raspbery Pi Pico Ws, sends them to InfluxDB, and displays them via web interface powered by Grafana.

Full home temperature and humidity monitoring

1. A network of Raspberry Pi Pico Ws with DHT22 sensors from which temperature and humidity data is served via http requests.
2. A centralized client which:
   1. Pulls data from the Picos
   2. Pushes that data into a local InfluxData instance
   3. Builds vizualizations for a web browser with Grafana

Result:

Who it's for

Anyone who needs granular data on temperature and humidity throughout their home. This is especially useful for homes that span multiple floors or have multiple HVAC zones.

The parts

1. Sensors -> hardware
   1. Raspberry Pi Pico W
   2. DHT22
2. Centralized client -> software
   1. This repo
   2. InfluxDB
   3. Grafana

Level 1 C4 model diagram of PicoTemps:

1. Sensors

Each sensor consists of two pieces of hardware:

1. A Raspberry Pi Pico W
2. A DHT22

Wiring the DHT22 to your Pico Ws

This assumes that your DHT22s came with a board that includes a resistor on GPIO pin.

DHT22 Pin	Pico Pin
+	3V
GPIO	GP2
-	GND

Pico Scripts

The /picofiles directory contains python files for the Raspberry Pi Pico Ws.

Install firmware

The Pico Ws must be running rp2-pico firmware > 1.19.1. Anything with network and socket precompiled will do. See this guide for instructions on installing the firmware.

Copy scripts

Once the firmware is in place:

1. Place a copy of ./picofiles/tempbotconfig.py on the Pico with customized values for the WiFi SSID and password and unique identifier for the Pico.
2. Place a copy of ./picofiles/tempBot.py on the Pico and rename it to main.py.

2. Centralized Client

You need a centralized client on the same network as the Pico Ws with PHP >= 8.1. In this case, we used a Libre Computer Le Potato; but any computer will do.

The client needs the following software:

1. This repo and its dependencies (including platform dependencies like PHP >= 8.1)

   $ git clone [e-mail]:balsama/picotemps.git
   $ cd picotemps
   $ composer install 
   

2. InfluxDB | See https://portal.influxdata.com/downloads/ for detailed instructions. Below is an example for ARM64 Ubuntu.

   $ wget -q https://repos.influxdata.com/influxdata-archive_compat.key
   $ echo '393e8779c89ac8d958f81f942f9ad7fb82a25e133faddaf92e15b16e6ac9ce4c influxdata-archive_compat.key' | sha256sum -c && cat influxdata-archive_compat.key | gpg --dearmor | sudo tee /etc/apt/trusted.gpg.d/influxdata-archive_compat.gpg > /dev/null
   $ echo 'deb [signed-by=/etc/apt/trusted.gpg.d/influxdata-archive_compat.gpg] https://repos.influxdata.com/debian stable main' | sudo tee /etc/apt/sources.list.d/influxdata.list
   $ sudo apt-get update && sudo apt-get install influxdb2
   

3. Grafana | See https://grafana.com/grafana/download/ for detailed instructions. Below is an example for ARM64 Ubuntu

   $ sudo apt-get install -y adduser libfontconfig1
   $ wget https://dl.grafana.com/oss/release/grafana_10.0.3_arm64.deb
   $ sudo dpkg -i grafana_10.0.3_arm64.deb
   

Configuration

Copy the config/example.config.yml file to config/config.yml and edit to match your setup. At a minimum, you will need to set values for:

1. sensors (sensor_id: ip_address)
2. influx (influx_url and influx_token) - the InfluxDB token can be generated from the InfluxDB web interface which can be found at port :8086 of the host machine by default.

Running/collecting

./scripts/run.php will poll each of the clients every ~20 seconds and push the data to InfluxDB. Or you can use scripts/run_once.php and call it periodically via cron.

Viewing the data

A sample Grafana dashboard is exported in JSON at grafana/grafana_dashboard_config.json. It will need to be tweaked to match your sensor IDs/rooms, but could be used as a starting point. The threshold mappings for temperature color coding could be especially useful.