Firmware archive tagged Apple for the logic board numbered 6050A3234201, with the MB-A01 suffix marking the main board at revision A01. The RAR is 7.89 MB and its exact contents are not described by the name, so expect a flash dump that needs inspection. The 6050A prefix belongs to the Inventec numbering pattern, so the board was built by an ODM rather than by Apple itself. Before programming, confirm the number silkscreened on the PCB, save a copy of the existing chip with your programmer, and verify the image size against 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 @BiosSchematicWorld. Enginerys does not host this file.
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 →