Here is the O variant of the PG12864 graphic LCD family, documented in a 59.7 KB PDF. The base number indicates a 128 by 64 pixel matrix. Expect a pin table, absolute maximum ratings, electrical characteristics and an outline drawing useful for fitting a replacement in a bezel. When a panel shows missing lines or no image, the sheet lets you confirm supply, contrast and control signals at the connector. Variants in this family differ in size and pin order, so compare the suffix carefully.
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.
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The standard format for schematics, block diagrams, power-sequence charts and service manuals.