Firmware update and recovery
ESP32 DoomsDay uses a main application partition and a small independent recovery updater. This design lets an SD update recover from an interrupted main-image write on a 4 MB flash device.
Ordinary SD update
- Download the main release file named like
esp32-doomsday-vX.Y.Z.bin. - Verify its SHA-256 value against the Firmware Center.
- Put it in
/OTA-Firmware-Update/on the microSD card. - Keep only the intended main update image in that directory.
- On the device, open Settings → Storage → Firmware update.
- Confirm and keep power stable until the system restarts.
Do not rename a factory image to look like a main image.
Image types
| Image | Purpose | Normal installation |
|---|---|---|
Main .bin | Routine firmware update | SD updater or wired flash at the documented main offset |
Recovery .bin | Repairs/replaces the independent updater | Wired flashing only |
Factory .bin | Bootloader, partition table, recovery, and main firmware merged | Wired flash at address 0x0 |
If an SD update is interrupted
Restore stable power and boot with the update SD card still inserted. The recovery updater can finish installing a valid main image. Do not repeatedly cycle power while it is writing.
Wired factory recovery
Factory recovery erases or replaces the installed flash layout. Back up microSD content separately; microSD files are not stored in internal flash, but removing the card before wired recovery avoids accidental confusion.
Use Espressif-compatible tooling, the correct ESP32-S3 USB device, and the exact address documented with the release. The merged factory image is written at 0x0.
Integrity matters
SHA-256 verifies that a download is byte-for-byte identical to the published artifact. It does not by itself prove who published it. Download only from the official Firmware Center and never install a binary from an untrusted message or file-sharing link.