BIOS-style EFI firmware for the Apple A1311, the 21.5-inch iMac of that era, on logic board 820-2494-A. Apple uses the 820 prefix for board numbers with a trailing revision letter; check both on the board before use. A technician writes this dump to the SPI flash with an external programmer when the original is corrupted. Save the existing chip contents first, since serial and system data are stored there, and make sure the image size matches the flash part.
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 @biosarchive. Enginerys does not host this file.
All sources (2)
The same file was posted more than once. If one link is dead, try the next.
| Channel | Posted | |
|---|---|---|
| @biosarchive | 18 Dec 2018 | Open file on RM Schematics |
| @one5technology | 10 Nov 2020 | Open file on RM Schematics |
How to open a .zip file
Compressed archive that every operating system opens without extra software.
Back up your own chip before writing any dump, and match the full board number and revision. Flashing guide →