ICP DAS USA I-7521 User Manual page 12

Pin assignment of 13-pin screw terminal block(I-7521/I-7521D):
Pin Name Description
1 X3
2 X2
3 X1
4 DO3
5 DO2
6 DO1
7 DI3
8 DI2
9 INIT*
10 D2+
11 D2-
12 +VS
13 GND
Pin assignment of COM1 connector (DB-9 Male):
Pin Name Description
1 Data+ DATA+ of RS-485 port
2 TXD
3 RXD
4 N/C
5 GND
6 N/C
7 CTS
8 RTS
9 Data- DATA- of RS-485 port
Note: The COM1 can be used as s RS-232 port or s RS-485 port. It
is not recommended to use both RS-232 & RS-485 at the same
time.
I-7521/I-7522/I-7522A/I-7523/I-7524/I-7527 User's Manual,Ver2.5 Aug.2015
Connects to I/O expansion board
Connects to I/O expansion board
Connects to I/O expansion board
Digital output, 150mA, 30V
Digital output, 150mA, 30V
Digital output, 150mA, 30V
Digital input, 3.5V ~ 30V
Digital input, 3.5V ~ 30V
Initial pin, 3.5V ~ 30V
DATA+ pin of COM2 (RS-485)
DATA- pin of COM2 (RS-485)
V+ of power supply (+10 to +30VDC
unregulated)
GND of power supply
Transmits Data (RS-232)
Receives Data (RS-232)
No Connection
Signal ground of RS-232
No Connection
Clear To Send (RS-232)
Request To Send (RS-232)
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