ra8835a RAIO Technology Inc., ra8835a Datasheet - Page 42

• Manufacturer Part Number: ra8835a
• Description: Dot Matrix Lcd Controller
• Manufacturer: RAIO Technology Inc.

RAiO TECHNOLOGY INC.
Version 1.0
7-10-2 Display Address Scanning
Note: One byte of display memory corresponds to one character.
Note: One bit of display memory corresponds to one pixel.
The basic screen configuration of the RA8835A series is as a single text screen or as overlapping
text and graphics screens. The graphics screen uses eight times as much display memory as the
text screen. Figure 7-11 shows the relationship between the virtual screens and the physical
screen.
The RA8835A series scans the display memory in the same way as a raster scan CRT screen.
Each row is scanned from left to right until the address range equals C/R. Rows are scanned
from top to bottom.
In graphics mode, at the start of each line, the address counter is set to the address at the start of
the previous line plus the address pitch, AP.
‧
‧
‧
‧
‧
‧
2
3
1
SAD+2AP
SAD+AP
SAD
SAD+AP
SAD+1
WS=0,FX=8
16
17
‧
‧
‧
‧
‧
‧
‧
24
+1
‧
‧
8
9
1
Figure 7-13: Character Parameters vs. Memory
SAD+2AP
Figure 7-12: Character Position Parameters
SAD+AP
SAD
SAD+AP
SAD+2
+2
C/R
SAD+AP
WS=0,FX=8,FY=8
SAD+1
+1
SAD+AP
SAD+2
+2
42/88
C/R
SAD+C/R
SAD+AP
+C/R
Line 2
Line 3
Line 1
SAD
SAD+1
SAD+2
SAD+C/R
SAD+AP
SAD+AP+1
SAD+AP+C/R
SAD+2AP
SAD+C/R
SAD+AP
+C/R
Dot Matrix LCD Controller
RA8835A
www.raio.com.tw
AP
AP