About three and a half years ago my boss came into work with a child's fire truck. He looked at my co-worker Deric and I and said "I want this thing to go off when the build fails.". It wasn't so much an order as it was half joking, half challenge. After about two years of keeping this in the back of my mind I thought it would be the perfect project to try the nodeMCU board on.
While Deric had since left the company, I still had the desire to unlock this firetrucks potential. What follows is a tale of features not asked for, hardware modification, custom connector fabrication, and a discovered love of JB-Weld.
The first steps
You'll have to forgive me. This is more of a post-mortem. I've had a large part of this project done for some time now, almost a year. I'll do my best to photoshop things to approximate what things were like but some of if is going to be obvious. I've already photoshopped some of it and you probably didn't even know.
So this is what we're working with. It looks simple enough. A circuit board with a speaker, a button, and two LEDs.