HD66789 Datasheet, PDF (137/156 Pages) Renesas Technology Corp – 528-channel, One-chip Driver for Amorphous TFT Panels with 262,144-color display RAM, Power Supply Circuit, and Gate Circuit

HD66789
Preliminary
Screen -split Drive Function
The HD66789 allows selectively driving two screens at arbitrary positions with the screen-drive position
registers (R42 and R43). Only the raster-rows required to display two screens at arbitrary positions are
selectively driven to reduce power consumption.
The first screen drive position register (R42) specifies the start line (SS17-10) and the end line (SE17-10)
for displaying the first screen. The second screen drive position register (R43) specifies the start line
(SS27-20) and the end line (SE27-20) for displaying the second screen. The second screen control is
effective when the SPT bit is set to 1. The total number of raster-rows driven for displaying the first and
second screens must be less than the number of liquid crystal drive raster-rows.
G1
1st Screen:
7 raster-row
G7
driving
Non-d i spl ay
ar ea
G26
2nd Screen:
17 raster-row
driving
G42
Non-d i spl ay
ar ea
The number of driven raster-rows : NL4-0 = “11110” (240 raster-rows)
1^st screen setting : SS17-10 = “00”H, SS17-10 = “06”H
2^nd screen setting : SS27-20 = “19”H, SS27-20 = “29”H, SPT = “1”
Screen-split Drive
Rev.0.12, May 09 2003, page 137 of 156