EM73P982 Datasheet, PDF (21/41 Pages) ELAN Microelectronics Corp – 4-BIT MICROCONTROLLER

EM73P982
4-BIT MICROCONTROLLER
There is only one kind of sleep/hold release mode.
1. Edge release mode:
Release sleep/hold condition by the falling edge of any one of P0(0..3)/WAKEUP0..3 or P8(0..3)/
WAKEUPA..D.
Note : There are 8 independent mask options for wakeup function in EM73P982. So, the wakeup function
of P0(0..3)/WAKEUP0..3 and P8(0..3)/WAKEUPA..D are enabled or disabled independently.
LCD DRIVER
It can directly drive the liquid crystal display ( LCD ) and has 40 segments, 8 commons output pins.
There are total 40x8 dots can be display. The VRLC pin is the LCD driver power input, there is the voltage
of ( Vcc - VRLC ) to LCD.
(1) LCD driver control command register:
Port27 3 2 1 0 Initial value: 0h
LDC * *
LCD DISPLAY CONTROL
LDC
Function description
00
LCD display disable
01
Blanking, change COMMON pin output
10
Reserved
11
LCD display enable
* : Don't care.
P27 is the LDC driver control command register. The initial value is 0000.
When LDC ( bit2 and bit3 of P27 ) is set to "0000", the LCD display is disabled.
When LDC is set to "0010", the LCD is blanking, the COM pins are inactive and the SEG pins continuously
output the display data.
The power switch of LCD driver is turned off when the CPU is reseted.
When LDC is set to "0110", the LCD display is enabled, the power switch is turned on and it can not be turned
off forever except the CPU is reseted again.
The power switch is also turned off during the sleep operation. Users must enable the LCD display again
by self when the CPU is waked up.
(2) LCD display data area:
The LCD display data is stored in the display data area of the data memory (RAM).
The display data area begins with address 20H during reset. The LCD display data area is as below:
RAM _{0 1 2 3 4 5 6 7 8 9 A B C D E F}
20H
C OM0
30H
C OM1
40H
C OM2
50H
C OM3
60H
C OM4
70H
C OM5
80H
C OM6
90H
C OM7
SSSS SSSS SS SS SSSS SSSS SSS S SSSS SSSS SSSS SSSS
EEEE EEEE EE EE EEEE EEEE EEE E EEEE EEEE EEEE EEEE
GGGG GGGG GG GG GGGG GGGG GGG G GGGG GGGG GGGG GGGG
0123 4567 89 11 1111 1111 222 2 2222 2233 3333 3333
01 2345 6789 012 3 4567 8901 2345 6789
* This specification are subject to be changed without notice.
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12.25.2001 21