8
ESTABLISHING AN RS-232 CONNECTION
Before you start:
Controlling a Smart-AVI device via RS-232 requires an RS-232 card installed on your computer or a USB
to RS-232 adapter. Below are instructions on how to create an RS-232 connection between a PC and the
Smart-AVI device.
Make sure to use communication settings 9600 bps, N, 8, 1, No flow control.
Check the device and your PC to determine if you need a male to male or a male to female cable and how
long it needs to be. The Smart-AVI device requires a straight through cable. You can use a Null Modem
Adapter to convert a crossed cable to a straight through cable. Examples of crossed and straight thorough
cable pin-outs are shown below. The standard maximum length for an RS-232 cable is 50 feet. Call our
Smart-AVI Support Engineer if you require more information.
Figure 8-1
Examples of 9 pin RS-232 Straight Through and Crossed Cables
Establish a connection to the Smart-AVI device:
1. Connect an RS-232 cable to the RS-232 connector on the PC.
2. Connect the other end of the cable to the RS-232 port of the Smart-AVI device.
3. Use Windows Control Panel / Device Manager to identify the Com port number. See instructions and
Figure 8-2 below.
4. Power on the device.
If you are using a USB to COM port adapter on a Win-
dows PC and need to identify the COM port used, do
the following:
1. Click on the start button.
2. Click on Control Panel.
3. Click on Device Manager. In Windows 7 you need
to click on “Hardware and Sound” to get to Device
Manager.
4. Click on the arrow next to Ports (COM & LPT). You
should see the name of your adapter and the
COM port number in use.
Figure 8-2
