Chapter 2 - connections – B&B Electronics RS-232 Digital I/O Module 232SDD16 User Manual
Page 5
232SDD16-1005 Manual
5
B&B Electronics -- PO Box 1040 -- Ottawa, IL 61350
PH (815) 433-5100 -- FAX (815) 433-5104
Chapter 2 - Connections
This chapter will cover the connections required for the
232SDD16. There are three sets of connections: digital I/O, serial
port, and power supply. Do not make any connections to the
232SDD16 until you have read this chapter.
Digital I/O Connections
Connections to the I/O lines are made through the DB25S
(female) I/O port connector. Refer to Table 2.1. See Chapter 5 for
I/O interfacing examples.
Digital Inputs
The digital input lines are CMOS/TTL compatible and can handle
voltages from 0Vdc to +5Vdc.
Digital Outputs
The digital output lines have a maximum voltage of +5Vdc and
are CMOS/TTL compatible.
Ground
The pin should be connected to your external digital devices
ground.
6 232SDD16-1005
Manual
B&B Electronics -- PO Box 1040 -- Ottawa, IL 61350
PH (815) 433-5100 -- FAX (815) 433-5104
Serial Port Connections
In order to communicate to the 232SDD16 module it must be
connected to an RS-232 serial port. The unit automatically detects
baud rates from 1200 to 9600. A data format of 8 data bits, 1 stop
bit and no parity is used.
The 232SDD16 is configured as a DCE
device (See Table 2.2). If your communications equipment is
configured as a DTE device, such as a standard IBM PC serial port,
the 232SDD16 should be connected using a “straight through” DB-
25 cable or a standard DB-9 to DB-25 cable adapter as shown in
Table 2.3. If your communications equipment is configured as a
DCE device, such as a modem, the 232SDD16 should be connected
using a “null modem” cable (See Table 2.4).
Table 2.1 - 232SDD16 I/O Port Pinout
DB-25S
Pin #
Function
DB-25S
Pin #
Function
1 No
connection
14 I/O
#15
2 No
connection
15 I/O
#14
3 No
connection
16 I/O
#13
4 No
connection
17 I/O
#12
5 No
connection
18 I/O
#11
6 No
connection
19 I/O
#10
7 Ground
20 No
connection
8
+12Vdc Input
21
I/O #9
9
I/O #0
22
I/O #8
10
I/O #1
23
I/O #7
11
I/O #2
24
I/O #6
12
I/O #3
25
I/O #5
13 I/O
#4