Specification sheet for the PC2004LRU-AEA-B character LCD module, supplied as a 142 KB PDF. In this style of numbering, 2004 denotes a 20 characters by 4 lines display, while the letters that follow describe backlight, viewing mode and other build options. Such sheets typically list the pin functions, supply and backlight ratings, interface timing and dimensions. Useful for checking why a panel shows blocks or nothing, setting contrast voltage, or confirming a replacement fits the same bezel and header.
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 @acodis_lcd_datasheets_EDID. 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.