Select the com port you want to test, Testing a comtrol device – Comtrol Multiport Modems Windows NT User Manual
Page 35

Comtrol Tools
35
Testing a Comtrol Device
4.
Select the COM port you want to test.
If the COM port does not exist or if it is currently being used by another
program, a Create File Error message appears.
If the COM port is available, a terminal window appears:
Note: Notice the <loop> button in the terminal window. If this option is
activated, it is green and uppercase (
), the COM port internal
loopback feature is activated, and the data is returned by the COM port
hardware. If this option is deactivated, it is gray and lowercase (
),
the internal loopback is deactivated, and the data is sent out of the COM
port.
Testing a Comtrol
Device
Use the following procedure to test the Comtrol device.
1.
Place a loopback plug on the COM port that you are testing. Make sure all
connectors are seated firmly and that the loop button is off.
Note: Test terminal works for RS-232 and RS-422 mode.
To build loopback plugs, see the hardware installation document for the
Comtrol device.
2.
From the Port menu, select Send Test Data. The program sends out a repeating
data stream.
Note: To stop the data stream, select the Send Test Data option again.
•
If the loopback plug is in place and the port is working correctly, the test
data should be echoed back to the screen.
•
If the loopback plug is not in place or the port is not working correctly, no
data or garbled data is echoed back to the screen.
Note: If no characters appear, try putting the loopback plug on an adjacent
port. It may be that you have the ports mixed up.