The B variant of the PG12864 graphic display is covered in this short 52.1 KB PDF datasheet. As a 128 by 64 dot module, it should be documented with pin assignments, electrical characteristics, interface timing and an outline drawing. Service technicians reference it to verify supply and contrast voltages, troubleshoot a blank screen, and find a fitting replacement for instruments or control equipment. Variants of PG12864 are not all interchangeable, so compare the letter and dimensions with the original part.
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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