An 842 KB PDF describing the LCD1602, the common 16-character by 2-line alphanumeric character display module. Such datasheets usually cover the connector pinout, supply and contrast voltage, backlight connections, the parallel interface timing and the controller command set. Technicians rely on it when a display shows blank boxes or nothing at all, checking the contrast pin, the enable and register-select signals and the data lines. Different manufacturers build 1602 modules, so compare backlight polarity and pin numbering with the actual board.
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