EM83055H
KEYBOARD ENCODER
GENERAL DESCRIPTION
The EM83055H microcontroller is dedicated to a keyboard encoder ,specially designed for IBM PC AT and
all compatible machines. The EM83055H controll all scan codes, three LEDs status, scan timing and communications
between the keyboard and PC. It is easy to implement a high performance, low cost keyboard with the minimal
external components.
FEATURES
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Low cost - eliminate need external components.
Phantom key detects.
RC oscillator ( 1.8432MHz ).
Support scan code set 1 ,2 and 3.
Support PC AT and PS/2 keyboard .
Low power CMOS device technology.
Internal pull-up resistor.
Tri-state outputs for easy board application.
Built-in 4K ROM.
Support WINDOWS
TM
95, 98, 2000, ME keys.
104/107 keys with multi-media or other special application keyboard encoder.
WINDOWS is registered trademarks of Microsoft corperation.
APPLICATION
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IBM PC AT or compatible machine keyboard.
IBM PS/2 model 30,50,60,80 or compatible machine keyboard.
Japanese keyboard.
Korean keyboard.
Brazilian keyboard.
European keyboard.
PIN ASSIGNMENTS
P90
CLK
DATA
OSCO
GND
R_OSCI
VDD
CAPS
39
38
37
5
4
3
2
1
P91
P92
P93
P94
P95
P50
P51
P52
P53
P54
6
7
8
9
10
11
12
13
14
15
EM83055H
36
35
34
33
32
31
30
29
28
27
NUM
SCROLL
P67
P66
P65
P64
P63
P62
P61
P60
* This specification are subject to be changed without notice.
P55
P56
P57
P80
P81
P82
P83
P84
P85
P86
P87
16
17
18
19
20
21
22
23
24
25
26
9.25.2001
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