GMS81C5108 Datasheet, PDF (76/102 Pages) Hynix Semiconductor – HYNIX SEMICONDUCTOR INC. 8-BIT SINGLE-CHIP MICROCONTROLLERS

19.3 LCD Display Memory
Display data are stored to the display data area (page 1) in
the data memory.
The display data stored to the display data area (address
0100_H-0124_H) are read automatically and sent to the LCD
driver by the hardware. The LCD driver generates the seg-
ment signals and common signals in accordance with the
display data and drive method. Therefore, display patterns
can be changed by only overwriting the contents of the dis-
play data area with a program. The table look up instruc-
tion is mainly used for this overwriting.
Figure 19.3 shows the correspondence between the display
data area and the SEG/COM pins. The LCD lights when
the display data is “1” and turn off when “0”.
LCD display memory in this location that are not used for
LCD display can be allocated for general purpose use.
The SEG data for display is controlled by RPR (RAM Pag-
ing Register).
RPR (RAM Paging Register)
R/W R/W R/W R/W
Bit : 7
6
5
4
3
2
1
0
-
-
-
-
-
-
RPR1 RPR0
ADDRESS : 0F3_H
RESET VALUE : ------00_B
RAM Page Instruction
0 Page CLRG
0 Page SETG
1 Page SETG
RPR1
x
0
0
RPR0
x
0
1
Figure 19-4 Setting of RAM Paging Register
GMS81C5108
Bit 0 1 2 3 4 5 6 7
SEG36
SEG35
SEG34
SEG33
SEG32
SEG31
SEG30
SEG29
SEG28
SEG27
SEG26
SEG25
SEG24
SEG23
SEG22
SEG21
SEG20
SEG19
SEG18
SEG17
SEG16
SEG15
SEG14
SEG13
SEG12
SEG11
SEG10
SEG9
SEG8
SEG7
SEG6
SEG5
SEG4
SEG3
SEG2
SEG1
SEG0
0124_H
0123_H
0122_H
0121_H
0120_H
011F_H
011E_H
011D_H
011C_H
011B_H
011A_H
0119_H
0118_H
0117_H
0116_H
0115_H
0114_H
0113_H
0112_H
0111_H
0110_H
010F_H
010E_H
010D_H
010C_H
010B_H
010A_H
0109_H
0108_H
0107_H
0106_H
0105_H
0104_H
0103_H
0102_H
0101_H
0100_H
Figure 19-5 LCD Display Memory
JUNE 2001 Ver 1.0
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