User Manual

1.5.5 Using D/I/O of the 7521(D)
(valid for 7521(D)/7522(D)/7524(D))
7521/2/2A/3/4/7 Series Hardware User’s Manual, Ver. 1.5 Sep/2002, 7Mh-001-15 -----36
Ext. GND
Ex
t.
24
V
10
9
8
7
6
11
5
4
12
1
3
GN
D
+
VS
D2
-
D2
+
DO3
D
O
1
DO2
DI1
/
Ini
t
2
1
D
ata
+
TXD
4
5
6
7
8
3
9
RXD
Data-
RTS
7
5
21
DI3
DI2
CTS
N/C
GND
N/C
X1
X2
X
3
3
2
1
COM1
Dry contact or TTL/CMOS
or (3.5V to 30V D/I)
Inductive load or
Conductive load
Current Limit Resistor
Load current <= 125mA
U?
2003A
1
3 14
2
4
5
6
9
16
15
13
12
11
107
8
B0
B2 C2
B1
B3
B4
B5
COM
C0
C1
C3
C4
C5
C6B6
E
DO1
DO2
DO3
GND
+VS
DIO24
DIO29
DIO30
7521
12
6
5
4
13
+5V
UA
74HCT08
1
2
3
R2
10K
R1
10K
D/I
TO_CPU
7521
D/I Block Diagram
D/O Block Diagram