This is a cross-platform interface for the Aranet4 CO₂ meter. You can use it to read values from the meter to then store in a database, display on a website, or generally do with whatever you want. Since the official mobile app for the device does not have automatic export features and the manual export is prone to failure, you can use this library instead for such purposes.
It is built with Bleak, a cross-platform Python Bluetooth client. It is also heavily inspired by Aranet4-Python, an excellent library that is unfortunately only compatible with Linux.
pip install pyaranet4
Before you do anything, make sure the device is properly paired. Once it is paired, pyaranet4 will usually be able to figure out the rest (e.g. the MAC address) by itself. Note that Bluetooth LE is a slow protocol, and most commands and calls will take a couple of seconds to complete. This is not an issue with the library, but a limitation of the technology.
pyaranet4 comes with a command-line utility, which is mostly compatible with Aranet4-Python's:
C:\> pyaranet4
--------------------------------------
Connected: Aranet4 06CDC | v0.4.4
Updated 56 s ago. Intervals: 60 s
2167 total readings
--------------------------------------
CO2: 511 ppm
Temperature: 25.05 C
Humidity: 58 %
Pressure: 1014.50 hPa
Battery: 98 %
--------------------------------------
Get stored historical values from the device:
C:\> pyaranet4 --history
index,timestamp,temperature,humidity,pressure,co2
1,2021-09-09 22:12:20,25.1,56,1014.5,584
2,2021-09-09 22:13:20,25.1,56,1014.5,590
3,2021-09-09 22:14:20,25.1,56,1014.5,579
...
Or save them to a file:
C:\> pyaranet4 --history --output-file=readings.csv
Or view the full list of command-line arguments and parameters:
C:\> pyaranet4 --help
You can also use pyaranet4 as a library:
from pyaranet4 import Aranet4
a4 = Aranet4()
print("Battery level: %s%%" % a4.battery_level)
print("Current CO₂ level: %i ppm" % a4.current_readings.co2)
print("Stored CO2 values:")
print(a4.history.co2)
The Aranet4
object has the following public properties and methods:
current_readings
(namespace): The current readings of the device's sensors, as a namespace with properties co2
(
integer), temperature
(float) pressure
(float), humidity
(integer), battery_level
(integer)
, update_interval
(integer), and since_last_update
(integer)current_readings_simple
(namespace): Identical to current_readings
, but without the update_interval
and since_last_update
properties; may be faster to requesthistory
(namespace): Historical readings stored on the device, as a namespace with properties co2
, temperature
, pressure
, humidity
, sensors
, and timestamps
. The sensor values are dictionaries with the interval index as
keys and the sensor reading as values. sensors
is a tuple of sensors included in the result. timestamps
is a
dictionary with indexes as keys and corresponding UNIX timestamps as values. The latter can be used to determine what
the timestamp of a given value is.mac_address
(string): The MAC address of the Bluetooth devicebattery_level
(integer): Battery level, 0-100.manufacturer_name
(string): The manufacturer of the device, e.g. SAF Tehnika
model_name
(string): The name of the device model, e.g. Aranet4
device_name
(string): The name of the device, e.g. Aranet4 06CDC
hardware_revision
(integer): Hardware revision number, e.g. 9
software_revision
(string): Software (firmware) version, e.g. v0.4.4
update_interval
(integer): Amount of seconds between sensor updatessince_last_update
(integer): Amount of seconds since last sensor updatestored_readings_amount
(integer): Amount of sensor readings stored on the deviceget_history(sensors: tuple, start: int, end: int)
(namespace): Same return type as history
, but allows one to
limit results to a given tuple of sensors and a given range of indexes, which can be faster to receive than the full
history. Sensors should be a tuple of a combination of Aranet4.SENSOR_CO2
, Aranet4.SENSOR_HUMIDITY
, and so on.