PDF of 67.9 KB filed as a schematic and named 28C64A, an A revision code within the 28C64 parallel EEPROM family. The name carries no manufacturer, speed grade or package information. Inside expect pin functions, write cycle behaviour and electrical specifications. A technician uses it to identify the part on a board, set up a programmer correctly and compare it with the B revision or other 28C64 sheets. Read the exact chip marking first and save the existing contents before any rewrite.
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.