HD66730 Datasheet, PDF (98/131 Pages) Hitachi Semiconductor – Dot-Matrix Liquid Crystal Display Controller/Driver Supporting Japanese Kanji, Korean Font Display

HD66730/HD66731
Partial Smooth Scroll
Partial smooth scroll displays one to three leftmost characters as fixed while the remaining ones undergo a
horizontal smooth scroll in the left and right direction. Specifically, the number of leftmost characters to be
fixed is specified by the partial scroll bits (PS1/0) in the scroll control register 2 (SCR2: R6). For example,
when bits PS1/0 are 10, the two leftmost characters are fixed; when 11, the three leftmost characters are
fixed.
Although half-size characters can be displayed in a fixed display area, they must be displayed in even-
numbered groups of two, four or six characters. Figure 31 shows an example of smooth scroll performed in
a display when bits PS1/0 are set to 10. The two leftmost characters ( ) are displayed as fixed, and the
remaining four characters undergo a smooth scroll.
Perform no shift
• PS1/0 = “10”
• SCR3 = “00” (Hex)
Shifts to the left by
one dot
• PS1/0 = “10”
• SCR3 = “01” (Hex)
Shifts to the left by
two dots
• PS1/0 = “10”
• SCR3 = “02” (Hex)
Shifts to the left by
three dots
• PS1/0 = “10”
• SCR3 = “03” (Hex)
Shifts to the left by
16 dots
• PS1/0 = “10”
• SCR3 = “0A” (Hex)
Shifts to the left by
32 dots
• PS1/0 = “10”
• SCR3 = “20” (Hex)
Figure 31 Example of Partial Smooth Scroll Display
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