February 21, 2016

Fun little BTLE tag

Bloomberg, the host of a recent Clang/LLVM hackathon, gave away Bluetooth 4.0 tags.

The whole thing is a clicky button. You turn it on or off by long-pressing. It comes with an app, but it’s easy to play with the basic features with a BTLE debug app. So far, it looks like I can…

  1. Get notified when the button is pressed.
  2. Turn on either of two alerts (which make it emit long beeps or short beeps).

I want to think of a little game that involves passing the tag around and clicking the button, maybe with a shared screen. A friend also had the idea of making a Bluetooth “theremin” by using round trip time as a proxy for distance, but it looks like something rate limits polling to once every ~0.5s after you read a value a few times quickly. It’d be interesting to figure out whether the OS X Bluetooth stack or the tag itself is doing it.

Either way, I’ll update this post if I do anything interesting.