On the hardware side of things, the test system is simply a NodeMCU connected to a buzzer and a MQ2 gas sensor. So how does it work? If the detector goes off while [Vivek] is cooking, he can tell ...

and one on the MQTT server side. Specifically, I’ll tackle the NodeMCU’s sleep mode to reduce power and step you through bridging MQTT servers to get your data securely out of your home server ...