Firmware dump for an Apple MacBook logic board numbered 820-3662, revision A. Apple uses 820-xxxx numbers to identify logic boards, and this code is printed on the PCB, so check it rather than relying on the model year. The 4.51 MB RAR is expected to contain an EFI or BIOS image for the SPI flash chip, written with an external programmer. Read and keep the original chip first, since it carries machine-specific data such as serial number, and verify that the image size matches the chip.
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 (5)
The same file was posted more than once. If one link is dead, try the next.
| Channel | Posted | |
|---|---|---|
| @biosarchive | 4 Apr 2019 | Open file on RM Schematics |
| @IT_SERVICE_WORLD | 28 Oct 2019 | Open file on RM Schematics |
| @pepeelectronica | 26 Apr 2022 | Open file on RM Schematics |
| @schematics_bios | 25 Jul 2026 | Open file on RM Schematics |
| @schematics_bios | 2 Aug 2026 | Open file on RM Schematics |
How to open a .rar file
Compressed archive — the usual wrapper for a schematic + boardview pair or a BIOS + EC set.
Back up your own chip before writing any dump, and match the full board number and revision. Flashing guide →