Flash firmware safely

Every SpaltX firmware file is signed and published with a SHA-256 checksum. Two minutes of checking prevents the two failure modes that actually brick boards: corrupted downloads and wrong targets.

Verify the download

Compute the file's SHA-256 and compare it to the value next to the download button:

• Windows: certutil -hashfile firmware.bin SHA256
• macOS / Linux: shasum -a 256 firmware.bin

If the value differs, delete the file and download again. Never flash a file that fails the check.

Match the target exactly

Firmware is built per board target, and a release only runs on the target it was built for. The target code is printed on the flight controller and listed on the drone model page under hardware revisions; the download page states the target for every release. Flashing the wrong target can leave the board unbootable, so match the code character for character.

Flash

1. Remove props. Always.
2. Connect USB and enter DFU (hold the boot button while plugging in, or use the configurator's reboot-to-DFU).
3. Load the verified file, flash, and wait for the automatic reboot — do not unplug mid-write.
4. Reconnect, confirm the version string, and restore your saved settings dump.

If a flash goes wrong

A failed write is almost always recoverable: re-enter DFU (boot button) and flash again with full-chip erase enabled. If the board no longer enumerates over USB at all, open a ticket with your order number and the target code and we'll work out whether it's a defect claim — see Returns, refunds, and RMA for how that runs.