BLE Exposure Notification Beeper
Allows you to build a simple device that beeps and flashes an LED whenever someone using a COVID-19 warning/tracing app that uses Bluetooth LE Exposure Notifications, like the german Corona-Warn-App, is seen nearby.
Notifiers (nearby devices with a warning app) are remembered for 20 minutes so it only beeps for newly detected ones. Note that the IDs will change every 15 minutes or so for privacy reasons, triggering new beeps.
Build your own
You need
- Any ESP32 board (like a WEMOS D32 or TTGO ESP32, preferrably with a LiPo battery controller).
- A 3V piezo buzzer (a simple speaker or headphones will also work).
- Optionally a LED.
- Optionally a small 1-cell LiPo battery.
- A nice case :)
Wiring
| ESP32 pin | goes to |
|---|---|
| 0 | LED (+) |
| 2 | Buzzer (+) |
| GND | LED (-), Buzzer (-) |
- Pins can easily be changed in code (
src/main.cpp).
Flashing the ESP32
- Easiest is to upload the latest binary, using NodeMCU PyFlasher .
- If you have platform.io installed, simply open the project and upload.
- You also need the arduino-esp32 platform and the lbernstone/Tone library.