EM65570
68COM/ 98SEG 65K Color STN LCD Driver
7.6 Display RAM Access Using the Windows Function
The EM65570 has a window area setting command for accessing a specified display
RAM area. To use the window function, you need to set up the X & Y address
positions. In addition, you also need to enable the auto-increment mode (AXI=”1”,
AYI=”1”). These two positions represent the window start position and window end
position. Set the X address (AX) and Y address (AY) registers to specify the window
start position of X and Y respectively. Set the Window X End address (EX) and
Window Y End address (AY) to specify the window end positions of X and Y
respectively. When accessing the window function, you can set AIM to “1” to modify
write access. You should set the following registers before accessing RAM when you
use the window function.
WIN = “1”, AXI=”1”, AYI=”1”
X Address, Y Address, Window X End Address, Window Y End Address
Moreover, the following address condition must be met:
Window end X address (EX) ≧ Window start X address (AX)
Window end Y address (EY) ≧ Window start Y address (AY)
X Direction
The Window
accessed area
X,Y Start Address
X,Y End Address
The entire RAM
display area
(shaded + Window
accessed areas)
Figure 7-8 Window XY Address Location within RAM Display
7.7 Display RAM Data and LCD
One bit of display RAM data corresponds to one dot of LCD. Normal display and
reverse display by the REV register are set up as follows:
Normal display (REV=0): RAM data = “0,” light OFF
RAM data = “1,” light ON
Reverse display (REV=1): RAM data = “0,” light ON
RAM data = “1” light OFF
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Product Specification (V1.0) 09.05.2005
(This specification is subject to change without further notice)
ELAN [ ELAN MICROELECTRONICS CORP ]
