HD66740 Datasheet, PDF (28/95 Pages) Hitachi Semiconductor – 112 x 80-dot Graphics LCD Controller/Driver

HD66740
Table 12 SL Bits and Display-start Raster-row
SL2
SL1
SL0
Display-start Raster-row
0
0
0
1st raster-row
0
0
1
2nd raster-row
0
1
0
3rd raster-row
0
1
1
4th raster-row
1
0
0
5th raster-row
1
0
1
6th raster-row
1
1
0
7th raster-row
1
1
1
8th raster-row
PS1–0: Specify PS1 to PS0 bits when SW = 1. When PS1–0 = 01, only the first line is fixed-displayed
in vertical smooth scrolling, and the other display lines are smooth-scrolled. When PS1–0 = 10, the first
and second lines are fixed-displayed. When PS1–0 = 11, the first to third lines are fixed-displayed.
For details, see the Partial Smooth Scroll Display Function section.
LCD-Driving-Pattern Control
B/C: When SW=1 and B/C=0, a B-pattern waveform is generated and alternates in every frame for LCD
drivin. When B/C=1, a C-pattern wavefrom is generated and alternates (n-raster-row reversed AC
drive) in each raster-row specified by bits EOR and NW4-NW0 in the LCD-driving-waveform control
register. For details, see the n-raster-row Reversed AC Drive section.
DCC: When SW=1 and DCC=0, a booster operates with the 64-divided clock of the operating frequency.
When DCC=1, the booster operates with the 32-divided clock. When the booster operates with the
64-divided clock, current consumptionin the booster is low, but boosting ability is weak.
R/W RS DB7 DB6 DB5 DB4 DB3 DB2 DB1 DB0
0 0 0 1 1 1 0 0 DCC B/C (SW = 1)
Figure 10a LCD-Driving-Waveform Control Instruction
LCD-Driving-Waveform Control
EOR: When the C-pattern waveform is set (B/C = 1) and SW = 1 and EOR = 1, the odd/even frame-select
signals and the n-raster-row reversed signals are EORed for alternating drive. EOR is used when the
LCD is not alternated by combining the set values of the LCD drive duty ratio and n raster-row. For
details, see the n-raster-row Reversed AC Drive section.
NW4–0: Specify the number of raster-rows n that will alternate at the C-pattern waveform setting (B/C =
1). NW4–NW0 alternate in every set value + 1 raster-row, and the first to the 32nd raster-rows can be
selected. When SW = 0, bits NW2, NW1, and NW0 can be set. When SW = 1, bits NW4 and NW3
can be set.
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