User guide

SW USB Series • Installation 8
Wiring for RS-232 Communication
RS-232 Port
The 3-pole, 3.5 mm captive screw connector labeled “RS-232” is used for optional RS-232
communication between the SW USB and a computer or control system. The control system
plugged into this port can issue commands to the SW USB, which can pass the commands
through to an Extron AV switcher that is plugged into the RS-232 Pass Thru port.
NOTE: The computer that you use for RS-232 control should not be one of the host
devices connected to any of the input ports.
To connect your computer or control system to the RS-232 connector, use a female 9-pin
D-to-bare-wire RS-232 cable, such as an Extron UC50 Universal Projector Control cable.
1. Wire the unterminated end of the RS-232 cable to one of the provided 3-pole captive
screw plugs.
2. Plug the wired 3-pole connector into the RS-232 receptacle on the SW USB rear panel.
Host PC Pin Switcher Pin
_
5 (Gnd)
2 (Rx) Tx
3 (Tx) Rx
NOTE: Connect a ground wire between
the switcher and the computer or
control system.
RS-232
To Computer or
Control System
RS-232 Port
SW USB Switcher
Rear Ranel
RS-232 Port
Tx Rx
9-pin
Connector
NOTE: If you use cable that has a drain
wire, tie the drain wire to ground
at both ends.
(Rx) Receive Pin to Transmit (Tx) Pin 3
Ground
(Tx) Transmit Pin to Receive (Rx) Pin 2
Figure 5. Wiring the RS-232 Connector