nodeMCU ESP82 Tripwire Episode 1

I recently picked up a nodeMCUv3 from AliExpress for real-cheap, and I’ve been looking at adding MQTT to my resume. I’ve also been wanting to make a wireless tripwire/movement sensor, so now seems like the perfect time to build one. I initially chose ThingSpeak as my cloud MQTT broker, but I recently found Adafruit IO (AIO), which allows a much faster update period (1 POST per 2 seconds vs. 1 POST per 30s for ThingSpeak). AIO also seemed to be a lot more intuitive and easy to use. Since the motion sensor is transmitting very simple data (“0” for heartbeat every so often, “1” when the sensor gets tripped), a complex data display/trigger setup isn’t required. AIO also uses a night theme, where ThingSpeak is blinding white. The choice was obvious.1

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