RA8835A
Version 1.0
Dot Matrix LCD Controller
7-12 Memory to Display Relationship
The RA8835A series supports virtual screens that are larger than the physical size of the LCD panel
address range, C/R. A layer of the RA8835A series can be considered as a window in the larger
virtual screen held in display memory. This window can be divided into two blocks, with each block
able to display a different portion of the virtual screen.
This enables, for example, one block to dynamically scroll through a data area while the other acts as
a status message display area. See Figure 7-20 and 7-21.
AP
C/R
SAD1
W/S=0
W/S=1
Character page1
Character page3
SAD1
SAD3
SAD3
Graphics page 1
Graphics page 3
Layer 1
Display page 1
Graphics page 2
Layer 1
SAD2
SAD4
Graphics page 2
Graphics page 2
Graphics page 4
Display page 2
Layer 2
C/R
Layer 2
CG RAM
SAD1
C/R
Character page1
SAD1
SAD3
Display page1
Display page3
C/R
Graphics page 3
SAD3
Layer 1
C/R
SAD2
SAD2
Display page2
Layer 2
Graphics page 2
C/R
SAD3
Character page3
C/R
SAD3
Graphics page 2
SAD2
SAD2
SAD1
Display page3
Display page2
C/R
Display page1
SAD1
Graphics page 1
Layer 1
Layer 2 Layer 3
Figure 7-20: Display Layers and Memory
RAiO TECHNOLOGY INC.
www.raio.com.tw
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RAIO [ RAIO TECHNOLOGY INC. ]
