Connecting rs-232 devices – Rockwell Automation 2706 DL20 SERIES G USER MANUAL User Manual
Page 116

Chapter 9
Installation and Maintenance
9–5
When connecting RS-232 devices refer to the following diagrams.
Note: The shield is connected to common at one end only. It is
recommended not to use the shield as a conductor; if necessary, use a
separate wire. Some devices may require certain hardware handshaking lines
to be asserted. Refer to appropriate documentation.
Connecting IBM XT or Compatible
Figure 9.2 shows how to connect an IBM XT or compatible computer.
Figure 9.2
Connecting IBM XT (25-Pin) or Compatible
DL20 RS-232 Port
SHIELD (frame ground)
TXD
RXD
SIGNAL GND
1
2
3
7
Computer COM1
(25-Pin) Serial Port
The wire colors refer to the Allen-Bradley 2706-NC1 and -NC2 cables.
RS-232 IN (CLEAR)
RS-232 OUT (RED)
GROUND (BLACK)
7
6
8
Connecting IBM AT or Compatible
Figure 9.3 shows how to connect an IBM AT or compatible computer.
Figure 9.3
Connecting IBM AT (9-Pin) or Compatible
DL20 RS-232 Port
SHIELD (frame ground)
RXD
TXD
SIGNAL GND
RS-232 IN (CLEAR)
RS-232 OUT (RED)
GROUND (BLACK)
1
2
3
5
Computer COM1
(9 Pin) Serial Port
The wire colors refer to the Allen-Bradley 2706-NC1 and -NC2 cables.
7
6
8
Connecting RS-232
Devices