
1
Features
Pin Compatible with NMOS 8255A
24 Programmable I/O Pins
Fully TTL Compatible
High Speed, No “Wait State” Operation with 5MHz
80C86
and 8MHz 80C88
Direct Bit Set/Reset Capability
Enhanced Control Word Read Capability
L7 Process
2.5mA Drive Capability on All I/O Ports
Low Standby Power (ICCSB) . . . . . . . . . . . . . . . . .10
μ
A
Description
the industry standard 8255A and is manufactured using a
self-aligned silicon gate CMOS process (Scaled SAJI IV). It
is a general purpose programmable I/O device which may be
used with many different microprocessors. There are 24 I/O
pins which may be individually programmed in 2 groups of
12 and used in 3 major modes of operation. The high
performance and industry standard configuration of the
make it compatible with the 80C86, and
other microprocessors.
Static CMOS circuit design insures low operating power. TTL
compatibility over the full military temperature range and bus
hold circuitry eliminate the need for pull-up resistors. The
advanced SAJI process results in performance equal
to or greater than existing functionally equivalent products at
a fraction of the power.
PA3
PA2
PA1
PA0
RD
CS
GND
A1
A0
PC7
PC6
PC5
PC4
PC0
PC1
PC2
PC3
PB0
PB1
PB2
PA4
PA5
PA6
PA7
WR
RESET
D0
D1
D2
D3
D4
D5
D6
D7
V
CC
PB7
PB6
PB5
PB4
PB3
13
14
15
16
17
18
19
20
1
2
3
4
5
6
7
8
9
10
11
12
28
27
26
25
24
23
22
21
40
39
38
37
36
35
34
33
32
31
30
29
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
Wing Shing Computer Components Co., (H.K.)Ltd.
Homepage:
http://www.wingshing.com
Tel:(852)2341 9276 Fax:(852)2797 8153
E-mail: wsccltd@hkstar.com
33
32
31
30
29
28
27
26
25
24
23
RESET
D
0
D
1
D
2.
D
3
D
4
D
5
D
6
D
7
V
CC
PB
7
CS
GND
A
1
A
0
PC
7
PC
6
PC
5
PC
4
PC
0
PC
1
PC
2
1
1
1
1
1
1
1
N
P
3
P
0
P
1
P
2
V
C
P
3
4
4
4
4
4
3
3
R
P
0
P
1
P
2
P
3
V
C
P
4
1
2
3
4
5
6
7
8
9
10
11
1
2
2
2
P
4
P
5
P
6
N
3
3
3
3
P
5
P
6
P
7
W
CS
GND
A1
A0
PC7
NC
PC6
PC5
PC4
PC0
PC1
P
P
P
P
P
P
P
P
P
N
NC
D4
D5
D6
D7
V
CC
RESET
D0
D1
D2
D3
R
P
P
P
P
P
P
P
P
W
N
P
44 43 42 41 40
39
38
37
36
35
34
33
32
31
30
29
28
27
1
2
3
4
5
6
26
25
24
23
22
21
20
19
18
7
8
9
10
11
12
13
14
15
16
17
CMOS Programmable peripheral
Interface
DIP-40
Pinouts
SPEED
QFP-44
44 QFP
44 PLCC
0 C to 70 C
0 C to 70 C
PLCC-44
WS82C55A-5P
WS82C55A-5C
WS82C55A-5Q
WS82C55A-5P
WS82C55AP
WS82C55A-5Q
WS82C55AQ
WS82C55A-5C
WS82C55AC
0 C to 70 C
PKG.
TEMPERATURE
RANGE
SPEED
8MHz
8MHz
8MHz
5MHz
5MHz
5MHz
PART NUMBERS
PART NUMBERS
40DIP
Ordering Information
The WS82C55A is a high performance CMOS version of
WS82C55A
WS82C55A
WS82C55AP
WS82C55AC
WS82C55AQ