Graphic LCD datasheet for PG192128LRS-BYA-B, a 284 KB PDF. The 192128 portion indicates a 192 x 128 dot panel, and BYA-B identifies a specific backlight colour, polarizer and revision build. Look here for connector pin assignment, logic and LCD bias voltages, controller interface timing, backlight current and outline drawing. It aids repair of instruments where the panel has lost contrast or the backlight has failed, and helps source a replacement. Check the full code on the module label, since the ANN variant differs in options.
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