ESP32 MagicBand+ BLE Broadcaster

A small ESP32-S3 project that broadcasts MagicBand+ BLE manufacturer packets and exposes a web interface (captive-portal style) to trigger light/vibration presets from a browser or scripts.

Quick summary: boot the device, connect to the access point (MagicBand-Controller by default), open the web UI, and send preset or custom commands to broadcast MagicBand+ packets over BLE.

Features

• BLE broadcaster: Sends MagicBand+ style manufacturer data to nearby devices.
• Wi‑Fi captive portal: The ESP runs an AP and DNS server so phones open the web UI automatically.
• Web UI + API: A small frontend is served from LittleFS; POST to /command to trigger effects.

Files of interest

• src/main.cpp: main firmware — BLE initialization, WiFi AP, captive DNS, web server routes and packet broadcast logic.
• frontend/ (frontend): static web files that are compiled and uploaded to LittleFS and served by the ESP (index.html, index.js, index.css).
• platformio.ini: PlatformIO project configuration (build/flash settings).
• partition_map.csv: Describes how to divide up flash to support littlefs

Hardware

• Any ESP32 board that supports BLE and LittleFS (ESP32-S3 is used in development). Make sure you have the appropriate board selected in platformio.ini.

Configuration

• AP SSID / password: change the constants at the top of src/main.cpp:
  • ap_ssid — default MagicBand-Controller
  • ap_password — default magicband123

How it works

• The web server serves files from LittleFS. The UI sends POST requests to /command with parameters to build manufacturer data packets.
• The firmware creates BLE advertisement manufacturer data and broadcasts for ~2 seconds.

Web API

• Endpoint: POST /command
• Parameters (form-data / x-www-form-urlencoded):
  • action (required): one of ping, preset, rainbow, dual, circle, crossfade
  • color, c1..c5: numeric color codes (or named values used by the UI) for presets
  • vib: vibration intensity (0–15)

Example curl commands

• Ping: curl -X POST http://192.168.4.1/command -F 'action=ping'
• Send a red preset with vibration level 3: curl -X POST http://192.168.4.1/command -F 'action=preset' -F 'color=red' -F 'vib=3'
• Send a 5-color rainbow (use numeric color codes for c1..c5): curl -X POST http://192.168.4.1/command -F 'action=rainbow' -F 'c1=15' -F 'c2=21' -F 'vib=2'

Building & flashing

• Open the project in VS Code with the PlatformIO extension.
• To build and upload firmware: use the PlatformIO task Upload (or run PlatformIO: Upload).
• To upload the LittleFS filesystem (the data/ folder containing the web UI): use PlatformIO's Build Filesystem Image and Upload Filesystem image task.

Notes & safety

• The firmware broadcasts manufacturer data as advertisements; no BLE connections are required.

Credits & references

• Based on information from: https://emcot.world/Disney_MagicBand%2B_Bluetooth_Codes (see code comments in src/main.cpp).