HD44780U Datasheet, PDF (35/59 Pages) Hitachi Semiconductor – Dot Matrix Liquid Crystal Display Controller/Driver

HD44780U
Since five segment signal lines can display one digit, one HD44780U can display up to 8 digits for a 1-line
display and 16 digits for a 2-line display.
The examples in Figure 19 have unused common signal pins, which always output non-selection
waveforms. When the liquid crystal display panel has unused extra scanning lines, connect the extra
scanning lines to these common signal pins to avoid any undesirable effects due to crosstalk during the
floating state.
HD44780
COM1
COM8
COM9
COM16
SEG1
SEG40
Example of a 5 × 8 dot, 8-character × 2-line display (1/5 bias, 1/16 duty cycle)
Figure 19 Liquid Crystal Display and HD44780 Connections (cont)
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