This project contains a PoC firmware for Espressif ESP32 chips (like ESP32-WROOM or ESP32-WROVER, but not ESP32-S2). After flashing our firmware, the device sends out Bluetooth Low Energy advertisements such that it can be found by Apple's Find My network.
Note that the firmware is just a proof-of-concept and currently only implements advertising a single static key. This means that devices running this firmware are trackable by other devices in proximity.
To change and rebuild the firmware, you need Espressif's IoT Development Framework (ESP-IDF). Installation instructions for the latest version of the ESP-IDF can be found in its documentation. The firmware is tested on version 4.2.
For deploying the firmware, you need Python 3 on your path, either as python3
(preferred) or as python
, and the venv
module needs to be available.
With the ESP-IDF on your $PATH
, you can use idf.py
to build the application from within this directory:
idf.py build
This will create the following files:
build/bootloader/bootloader.bin
-- The second stage bootloaderbuild/partition_table/partition-table.bin
-- The partition tablebuild/openhaystack.bin
-- The application itself
These files are required for the next step: Deploy the firmware.
Use the flash_esp32.sh
script to deploy the firmware and a public key to an ESP32 device connected to your local machine:
./flash_esp32.sh -p /dev/yourSerialPort "public-key-in-base64"
Note: You might need to reset your device after running the script before it starts sending advertisements.
For more options, see ./flash-esp32.h --help
.