User`s manual

5.2.3 Address decode & D/O CKT
VCC
CLKOUTA ARDY
INT0 INT1
VCC RESET
RESET\
TO_0 TO_1
TI_0 TI_1
SCLK DIO9
DIO4 DIO14 DO8
VCC DO9
DO10
DO11
DO12
DO13
DO14
DO15
A0 D0 DO0
A1 D1 DO1
A2 D2 DO2
A3 D3 DO3
A4 D4 DO4
A5 D5 DO5
A6 D6 DO6
D7 DO7
WR\
CS\ RD\
VCC
C3
10u
C1210
C1
.1u
C0805
J1
CON20A
JDIP20P
1
3
5
7
9
11
13
15
17
19
2
4
6
8
10
12
14
16
18
20
J2
CON20A
JDIP20P
1
3
5
7
9
11
13
15
17
19
2
4
6
8
10
12
14
16
18
20
U2
74LS273
SOL20
3 2
4 5
7 6
8 9
13 12
14 15
17 16
18 19
11
1
D1 Q1
D2 Q2
D3 Q3
D4 Q4
D5 Q5
D6 Q6
D7 Q7
D8 Q8
CLK
CLR
U1
74HCT138
SOIC16
1
2
3
6
4
5
15
14
13
12
11
10
9
7
A
B
C
G1
G2A
G2B
Y0
Y1
Y2
Y3
Y4
Y5
Y6
Y7
C2
.1u
C0805
U3
74LS273
SOL20
3 2
4 5
7 6
8 9
13 12
14 15
17 16
18 19
11
1
D1 Q1
D2 Q2
D3 Q3
D4 Q4
D5 Q5
D6 Q6
D7 Q7
D8 Q8
CLK
CLR
GND
GNDGND
VCC=20
GND=10
VCC=16
GND=8
outportb(0)
outportb(1)
The CS\ will be active if program input/output from I/O address BASE+0 to
BASE+0xff.
Write value_1 to DO 0 to 7  outportb (BASE+0, value_1);
Write value_2 to DO 8 to 15  outportb (BASE+1, value_2);
The power-up default value of BASE is 0.
It is not recommended to change the value of BASE from 0 to another value.
I/O Expansion Bus for 7188X/7188E User’s Manual, Jun/2004 v1.4, 7PH-000-14---27