So I've got a fun thing that my roommate got at an e-waste place, and I'm gonna open it up and see how it works and if I can interface with it.

It's... a crosswalk button/speaker!

At the bottom it's got interface stuff.
We've got COM and +, USB-B, and unpopulated EXT button and EXT Speaker ports.
There's also some LEDs: Mode, Data, and Audio

And there's nothing on the back, just a grate for a speaker.

There are some labels: EN2 533586 17119416 and V4.05

So, inside. We've got this huge coil thing (more on that later), a single PCB, and a 6W speaker. This fucker is gonna be LOUD, I'm sure of it.

So the coil thing is the button!
See, on the inside of the front, there's a piece of metal, a rubber spacer, and a magnet.

When you push the button, the metal flexes a little, the magnet moves, and this coil can pick it up.

This is presumably used because this is a button that has to be very vandalism-proof