Datasheet for the PG240128LRS-ATA-H graphic LCD module, a 193 KB PDF. The 240128 figure corresponds to a 240 x 128 pixel matrix, and the ATA-H ending identifies a specific option set and revision different from other LRS variants. Inside you can expect pin assignments, electrical characteristics, backlight specifications, interface timing and a dimensioned drawing. It serves when tracing why a panel stays blank, adjusting contrast supply, or choosing a compatible replacement. Check the exact code on the module, since backlight and voltage options vary between suffixes.
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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