A BIOS / firmware dump for HP hardware. Shared as “hp all in one 21-a255in”, 8.00 MB.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @jdbios_world. Enginerys does not host this file.
Back up your own chip before writing any dump, and match the full board number and revision. Flashing guide →