Named for the Catalyst Semiconductor 24WC129, this 74.3 KB PDF is catalogued as a schematic but serves as the part datasheet for a 128 Kbit class I2C serial EEPROM. It should cover pinout, device addressing, write protection and page write details, which may differ from the sibling 24WC128. Use it to confirm the correct variant before setting up a programmer, and to check the address pins and pull-up resistors on the board. Saving the original memory contents before writing remains the safe first step.
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.