Specification PDF for the PC1602LRU-QSO-H LCD module, the 1602 number meaning the familiar 16 characters by 2 lines format. The QSO-H tail is the variant code, which can change backlight, polarizer or temperature grade. Such datasheets list connector pins, supply ratings, backlight figures, command timing and dimensions. On the bench it supports checking a blank or blocky display, measuring the contrast pin, and confirming that a substitute 16x2 module shares the same pinout and mounting holes.
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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