| I would have just had the CO2 level read via a $8 I2C device connected to an Esp8266/Esp32 running Arduino. I would post the result to a web service in this fashion from the Esp8266: https://techtutorialsx.com/2016/07/21/esp8266-post-requests/ Then just setup a nice Graphana+Prometheus as a service, graphana.com is nice and can expose a Prometheus end point over basic http auth - easy to post to. Then you can setup alerts, graphs, dashboards, etc. In fact you could have a whole suite of IoT reports flowing in from various Arduinos really easily. Or at least a couple CO2 sensors spread around the house. Total investment of coding would be about 30-50 lines of Arduino code for the Esp8266 and you may even get away with the free plan on Graphana.com. I obviously like to outsource as much as possible these days. Less learning, but more efficient. |