AiO Sensor CO, CO2, NOx, VOC, PM, temp, hum

Currently the airrohr firmware supports temperatur, rel. humidity and PM.

There are sensors on the market for CO2, CO, NOx, VOC. Some of them not cheap.
But all of them together would deliver an load of information about air quality.

So my wish for christmas is an All in One (AiO) firmware which is able to measure CO, CO2, NOx, VOC, PM, Temperature, rel. Humidity, Temperature and Dew Point (calculated).

I know that the ESP8266 has not enough ROM/RAM for this, so it would be ESP32 only?

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Yes, and don’t forget ozone. I am currently implementing the SEN55, it can measure PM, T, h, VOC, NOx (the latter two just as an index). For now I can write the data to as if it is a SPS30+SHT3x, but I don’t know where to write the VOC and NOx index to (writing my own software).
It seems that there is support for NO2 measurements: the NO2_A43F sensor can be selected in but the documentation does not mention how to connect this sensor to the esp. I even scanned through the firmware on Github but I haven’t found any mention of this sensor so it is questionable if it is really supported. But one can write its own software and send the proper json string to api and it should work. Problem however is that there is no documentation about the json “value_type” that needs to be added. PIN number is 17, I could find that by enabling expert fields in So the json header needs to include X-Pin:17.

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When new software with this sensor will be available?
Is it possible to make second version for ESP32, beside ESP8266?



The sensors are fully open source. I can explain…

A team in France experience huge difficulties to calibrate NOx sensors. The are extremly sensitive to RH.

I have a version for ESP32 but the https still does not work. I am currently seeking for an idea.

Polish team from nettigo has add-on as a heater in their own version, which reduces impact of RH on PM measurement. Maybe here in this case it would be good idea to warm air before measurement.

Isn’t it possible just to compile current software on ESP32 without any other features? And then just add new ideas?

Isn’t it possible just to compile current software on ESP32 without any other features? And then just add new ideas?

It is possible. I do it every day. But for normal end user, we have to set up something in the flasher, make the firmware 100 % stable etc. We have talked about it just a few days ago with the team and we need a https suport for the esp32.
Even the esp32 has its limitations : 2 UART no more no less for example. So you would have to find I2C sensors.