Aranet 4 & Tuya Bluetooth hub

Cthloconnor · September 8, 2023, 10:27pm

I have an Aranet4 CO2 sensor which has been picked up by the Bluetooth integration in HA, however in my wisdom I bought a Tuya Bluetooth wifi hub to get readings from the upstairs bedrooms - the hub doesn’t see the Aranet4 sensor. Any advice how pair them or at least have the hub query the sensor & receive data? Thanks

dproffer · September 8, 2023, 11:55pm

From my experience with two of the Aranet CO2 devices, they are not part of the ‘Tuya universe’. They have their own Bluetooth BLE protocols. If you upgrade the firmware of these Aranet devices you can set an option so they broadcast their CO2, temperature, pressure, humidity, battery and rssi values as BLE advertising packets. This is the simplest way to get the realtime data from these devices without having to pair the device to your receiving BLE device/gateway and setup a session.

I was able to decode this data using the OpenMQTTGateway system to create MQTT messages that can be used to create Home Assistant sensors, example output below.

I am not familiar with the Tuya Bluetooth BLE to WiFi hub, however if you can get it to capture the raw BLE advertising packets from any device, not only those in Tuya universe. And if you can forward these captured packets to a decoder program, you should be able to accomplish the same results I am getting with the Open MQTT Gateway system.

In this link is a python sample to decode the Aranet4 advertising packets:

gist.github.com

https://gist.github.com/deepcoder/3aa75b2368e048c030bc5f79f9870680

gistfile1.txt

#! /usr/bin/env python3
# aranet4-decode.py
# decode aranet4 co2 monitor BLE advertising packets
# 202302091406
#
# https://github.com/Anrijs/Aranet4-ESP32/blob/main/src/Aranet4.h
# ":" (colon) in C struct - what does it mean? [duplicate]
# https://stackoverflow.com/questions/8564532/colon-in-c-struct-what-does-it-mean
#
# typedef struct AranetManufacturerData {

This file has been truncated. show original

I am very happy with the Aranet4 devices, the reading seem very accurate. Good hunting!

https://docs.openmqttgateway.com/

Cthloconnor · September 9, 2023, 6:57am

Thank you David, that’s a great steer- I’ll try to implement this information to the best of my ability. Cathal

DigiH · September 10, 2023, 2:46pm

Hi @dproffer,

We’d still be interested to create an official decoder for the Aranet CO2 sensor with this firmware for OpenMQTTGateway/Theengs Gateway/Theengs Decoder, as I’ve commented in your gist.

Any chance of a few OpenMQTTGateway data sample messages?