HT82K28A_02 Datasheet, PDF (1/16 Pages) Holtek Semiconductor Inc – Win98 Keyboard Encoder

HT82K28A
Win98 Keyboard Encoder
Features
· Designed for Windows 95/98/NT
· Supports 3 Windows 95 Keys
· Supports Power, Sleep and Wake-up Windows 98
ACPI functions
· Supports Japanese, Korean and Portuguese
· Supports Japanese DOS/V 106-key keyboard
· Supports code set 1, for PS/2 model 30 keyboard
· Supports code set 2, for PC/AT, PS/2 model 50,60
keyboards
· Supports code set 3, for PS/2 model 80 keyboard
· RC oscillator
· Phantom key detection
· Minimal external components
· 40-pin DIP package
General Description
The HT82K28A is a keyboard encoder especially de-
signed for IBM PC/AT, IBM PS/2 and all compatible ma-
chines.
The HT82K28A accepts keyboard inputs and contains a
16-character first-in-first-out buffer in which data is
stored. An inexpensive RC oscillator can be used for the
system clock. The device offers the advantage of simple
implementation in high performance and low cost key-
board applications.
Pin Assignment
O SC1
VSS
VDD
VSS
IO 0
IO 1
C2
C3
C4
C5
C6
C7
R 10
R 11
R 12
R0
R1
R2
R3
R4
1
40
2
39
3
38
4
37
5
36
6
35
7
34
8
33
9
32
10
31
11
30
12
29
13
28
14
27
15
26
16
25
17
24
18
23
19
22
20
21
H T82K 28A
4 0 D IP -A
C1
C0
D ATA
C LO C K
R 18
R 17
NC
R 16
CAP
NUM
SCRL
R9
R8
R 15
R 14
NC
R 13
R7
R6
R5
Rev. 1.30
1
June 27, 2002