Small 137 KB ZIP archive for the ASUS X555LD, labelled version 3.1, which most likely refers to the board revision. The name gives no detail on contents, so it may hold a boardview, schematic or firmware; open it to confirm. ASUS mainboards normally carry the model name and a REV number on the PCB, and that revision should match before relying on any file. Given the size, it could be an EC or keyboard-controller firmware image or a compact boardview, used for repair diagnostics or reflashing with a suitable programmer.
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 @schematicslaptop. Enginerys does not host this file.
All sources (18)
The same file was posted more than once. If one link is dead, try the next.
How to open a .zip file
Compressed archive that every operating system opens without extra software.