Flashing custom firmware
Firmware you build yourself is for personal use and isn't supported by Nabu Casa. Nabu Casa support can't help with custom configurations, including Grove sensors. While Connect AUX-2 runs your own firmware, it doesn't receive over-the-air firmware updates from Nabu Casa. To return to the supported firmware at any time, reinstall the factory firmware. See Restoring the factory firmware.
Home Assistant Connect AUX-2 uses an ESP32-S3 with an unlocked bootloader. It ships with firmware built on ESPHome, and you can flash your own custom firmware. The firmware source is the starting point. For building and distributing a custom build, see Building ESPHome components.
Custom firmware is optional.
Install your own firmware over USB the first time. The EN 18031 cybersecurity standard requires this.
Restoring the factory firmware
To return to the factory firmware after running custom firmware, use the web installer.
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