Named 28F102, this 116 KB PDF is filed as a schematic but the code points to a 28F-family parallel flash memory device rather than a board. No manufacturer or revision appears in the name. A technician would open it for the pin map, organisation, program and erase algorithm and electrical limits. Such data matters when selecting the correct chip profile in a programmer or confirming that a replacement part is equivalent. Verify the marking on the chip itself and keep a backup image before any erase cycle.
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 @cyberlanelectonik. Enginerys does not host this file.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.