Recently I deployed another prototype in our local hackerspace.

Node measure room humidity and temperature and send data to local MQTT broker.

Local broker is based on A5-V11 router with compiled OpenWRT system. Reason for why I had to build router image by myself is that I had to remove some packages to get fit necessary software into device flash storage.

Data are send to central broker where they are transformed into ThingSpeak channel updates. You can look at final graphs at hackerspace project page (czech).

Currently I'm working on PCB design of my node with PoE, reliable power source and RJ-11 connector for sensor. I'll post new project update shortly.