Raw 8 MB firmware image for an Apple logic board numbered 820-3227, saved as a plain .bin file. The name only indicates an output image without a firmware version, so treat it as an unverified dump. Apple uses the 820-xxxx pattern for logic board part numbers, which must match the number printed on the PCB. Before writing it with an SPI programmer, read and keep the original chip contents, because Mac firmware holds machine-specific data such as serial and network information that a generic image will not carry.
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 @efibios. Enginerys does not host this file.
How to open a .bin file
A raw, byte-for-byte image of a flash chip: the main BIOS / UEFI, the embedded-controller (EC) firmware, or both.
Back up your own chip before writing any dump, and match the full board number and revision. Flashing guide →