GMS81C5108 Datasheet, PDF (77/102 Pages) Hynix Semiconductor – HYNIX SEMICONDUCTOR INC. 8-BIT SINGLE-CHIP MICROCONTROLLERS

GMS81C5108
19.4 Control Method of LCD Driver
Initial Setting
Flow chart of initial setting is shown in Figure 19-6.
Example: Driving of LCD
Select Frame Frequency
LDM
:
LDM
SETG
Clear
LCD Display
Memory
Turn on LCD
LDX
C_LCD1: LDA
STA
CMPX
BNE
CLRG
:
SET1
:
.
LCR,#12H
RPR,#1
#0
#0
{X}+
#025H
C_LCD1
LCR.5
Setting of LCD drive method
Initialize of display memory
Enable display
Figure 19-6 Initial Setting of LCD Driver
Display Data
Normally, display data are kept permanently in the pro-
gram memory and then stored at the display data area by
the table look-up instruction. This can be explained using
character display with 1/4 duty LCD as an example as well
as any LCD panel. The COM and SEG connections to the
LCD and display data are the same as those shown is Fig-
ure 19-7. Following is showing the Programming example
for displaying character.
;f_F=64Hz, 1/4 duty(f_SUB= 32.768kHz)
;Select LCD Memory(1 page)
;RAM Clear
;(0100H->0124H)
;Enable display
COM0
COM1
SEG0
SEG1
COM2
COM3
Example: display “2”
bit 7 6 5 4
100_{H * * * *}
32 10
00 11
101_{H * * * *} 1 1 1 0
Note: * are don’t care.
Figure 19-7 Example of Connection COM & SEG
Note: When power on RESET, sub oscillation start up time
is required. Enable LCD display after sub oscillation is sta-
bilized, or LCD may occur flicker at power on time shortly.
74
JUNE 2001 Ver 1.0