/waveplus-reader

Primary LanguagePythonMIT LicenseMIT

Airthings Wave Plus Sensor Reader

This is a project to provide users an interface (read_waveplus.py) to read current sensor values from the Airthings Wave Plus devices using a Raspberry Pi 3 Model B over Bluetooth Low Energy (BLE).

Airthings Wave Plus is a smart IAQ monitor with Radon detection, including sensors for temperature, air pressure, humidity, TVOCs and CO2.

Table of contents

Requirements

The following tables shows a compact overview of dependencies for this project.

List of OS dependencies

OS Device/model/version Comments
Raspbian Raspberry Pi 3 Model B Used in this project.
Linux x86 Debian Should work according to bluepy

List of linux/raspberry dependencies

package version Comments
python 2.7 Tested with python 2.7.13
python-pip pip for python2.7
git To download this project
libglib2.0-dev For bluepy module

List of Python dependencies

module version Comments
bluepy 1.2.0 Newer versions have not been tested.
tableprint 0.8.0 Newer versions have not been tested.

Setup Raspberry Pi

The first step is to setup the Raspberry Pi with Raspbian. An installation guide for Raspbian can be found on the Raspberry Pi website. In short: download the Raspbian image and write it to a micro SD card.

To continue, you need access to the Raspberry Pi using either a monitor and keyboard, or by connecting through WiFi or ethernet from another computer. The latter option does not require an external screen or keyboard and is called “headless” setup. To access a headless setup, you must first activate SSH on the Pi. This can be done by creating a file named ssh in the boot partition of the SD card. Connect to the Pi using SSH from a command line interface (terminal):

$ ssh pi@raspberrypi.local

The default password for the “pi” user is “raspberry”.

Turn on the BLE interface

In the terminal window on your Raspberry Pi:

pi@raspberrypi:~$ bluetoothctl
[bluetooth]# power on
[bluetooth]# show

After issuing the command show, a list of bluetooth settings will be printed to the Raspberry Pi terminal window. Look for Powered: yes.

Installing linux and python packages

Note: The read_waveplus.py script is only compatible with Python2.7.

The next step is to install the bluepy Python library for talking to the BLE stack. For the current released version for Python 2.7:

pi@raspberrypi:~$ sudo apt-get install python-pip libglib2.0-dev
pi@raspberrypi:~$ sudo pip2 install bluepy==1.2.0

Make sure your Raspberry Pi has git installed

pi@raspberrypi:~$ git --version

or install git to be able to clone this repo.

pi@raspberrypi:~$ sudo apt-get install git

Additionally, the read_waveplus.py script depends on the tableprint module to print nicely formated sensor data to the Raspberry Pi terminal at run-time.

pi@raspberrypi:~$ sudo pip2 install tableprint==0.8.0

Note: The read_waveplus.py script has been tested with bluepy==1.2.0 and tableprint==0.8.0. You may download the latest versions at your own risk.

Downloading script

Downloading using git:

pi@raspberrypi:~$ sudo git clone https://github.com/Airthings/waveplus-reader.git

Downloading using wget:

pi@raspberrypi:~$ wget https://raw.githubusercontent.com/Airthings/waveplus-reader/master/read_waveplus.py

Usage

To read the sensor data from the Airthings Wave Plus using the read_waveplus.py script, you need the 10-digit serial number of the device. This can be found under the magnetic backplate of your Airthings Wave Plus.

If your device is paired and connected to e.g. a phone, you may need to turn off bluetooth on your phone while using this script.

cd into the directory where the read_waveplus.py script is located if you cloned the repo.

The general format for calling the read_waveplus.py script is as follows:

read_waveplus.py SN SAMPLE-PERIOD [pipe > yourfilename.txt]

where the input arguments are:

input argument example Comments
SN 0123456789 10-digit number. Can be found under the magnetic backplate of your Airthings Wave Plus.
SAMPLE-PERIOD 60 Read sensor values every 60 seconds. Must be larger than zero.
pipe pipe > yourfilename.txt Optional. Since tableprint is incompatible with piping, we use a third optional input argument "pipe".

Note on choosing a sample period: Except for the radon measurements, the Wave Plus updates its current sensor values once every 5 minutes. Radon measurements are updated once every hour.

Printing data to the terminal window

By default, the read_waveplus.py script will print the current sensor values to the Rasberry Pi terminal. Run the Python script in the following way:

pi@raspberrypi:~/waveplus-reader $ sudo python2 read_waveplus.py SN SAMPLE-PERIOD

where you change SN with the 10-digit serial number, and change SAMPLE-PERIOD to a numerical value of your choice.

After a short delay, the script will print the current sensor values to the Raspberry Pi terminal window. Exit the script using Ctrl+C.

Piping data to a text-file

If you want to pipe the results to a text-file, you can run the script in the following way:

pi@raspberrypi:~/waveplus-reader $ sudo python2 read_waveplus.py SN SAMPLE-PERIOD pipe > yourfilename.txt

where you change SN with the 10-digit serial number, and change SAMPLE-PERIOD to a numerical value of your choice.

Exit the script using Ctrl+C.

Sensor data description

sensor units Comments
Humidity %rH
Temperature °C
Radon short term average Bq/m3 First measurement available 1 hour after inserting batteries
Radon long term average Bq/m3 First measurement available 1 hour after inserting batteries
Relative atmospheric pressure hPa
CO2 level ppm
TVOC level ppb Total volatile organic compounds level

Contribution

Let us know how it went! If you want contribute, you can do so by posting issues or suggest enhancement here, or you can open a pull request for review here.

Release notes

Release dated 04-Dec-2020

  • [bug] Fixed missing little-endian specifier.

Release dated 14-Jan-2019

  • [bug] Fixed issue (#4)

Release dated 14-Dec-2018

  • Added SAMPLE-PERIOD as an input argument.

Initial release 12-Dec-2018