Cyclades AlterPath ACS, Command Reference Manual

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Troubleshooting
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Port Conversation
This test sends and receives data on the selected port. One way to run this test is to place
a loop-back connector on the port to be tested and begin. Enter the number of the port
and a baud rate (9600 is a typical value). Type some letters, and if the letters appear on
the screen, the port is working. If the letters do not appear on the screen (which also
occurs if the loop-back connector is removed), the port is not functioning correctly.
A second method that can be used to test the port is to connect it to a modem with a
straight cable. Begin the test and type “at”. The modem should respond with “OK”,
which will appear on the screen. Other commands can be sent to the modem or to any
other serial device. Press Ctrl-Q to exit the terminal emulation test.
Test Signals Manually
This test confirms that signals are being sent and received on the selected port. Neither
the loop-back connector nor the cross cable are necessary. Enter the number of the port
to be tested and begin the test.
Figure B.1 - Initial Test
First, type Ctrl-D to see the X in the DTR column move position, then type Ctrl-R to see
the X in the RTS column change position. If each of the Xs moves in response to its
command, the signals are being sent. Another method to test the signals is to use a loop-
back connector. Enter the number of the port with the loopback connector and start the
test. In this case, when Ctrl-D is typed, the Xs in the first three columns will move as
shown below.
Figure B.2 - Second screen, showing changed positions
This is because the test is receiving the DTR signal sent through the DCD and DSR pins.
When Ctrl-R is typed, the Xs in the RTS and CTS columns should move together. If the
Xs change position as described, the signals are being sent and received correctly.