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Firmware Updates ​

The firmware update process uses a secure Serial OTA (Over-The-Air) method over USB, handling encrypted .enc files.

Primary Method (Software Reboot) ​

  1. The desktop app sends a START_UPDATE command over USB.
  2. The ESP32-S3 chip forces a reboot directly into the hardware ROM bootloader.
  3. Once in flash mode, the desktop app uses a hidden instance of esptool to silently flash the new decrypted firmware.

Fallback Method (Serial OTA) ​

If the ROM bootloader is locked:

  1. The desktop app sends the encrypted .enc in chunks over USB.
  2. The ESP32-S3 reads the chunks, decrypts them in RAM using an AES key.
  3. It writes them to the secondary OTA flash partition before restarting.