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Troubleshooting
CTA 500
dm On Line Guide
P0873832 Issue 05
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If the cable is faulty or the ICS is down, the attached phone will
also not work.
AT command problem?
The CTA 500
dm does not respond to AT commands sent from
your PC.
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Make sure that your PC, terminal or other DTE is conÞgured
correctly.
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Check the DTE connection. If the DTE is conÞgured as a DCE
you may need a null modem cable.
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Check that your PC or DTE is conÞgured to expect CD and CTS
signals. See
ÒSerial Interface Control LinesÓ on page 56
for
more information.
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Check that the CTA 500
dm
is in the command mode.
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Check that your PC or DTE is conÞgured to provide a DTR
signal. See
ÒSerial Interface Control LinesÓ on page 56
for more
information.
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If the LED is ßashing quickly, refer to the
ConÞguration
section
of this document.
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Check that the CTA 500
dm
serial port is set to the correct baud
rate (115200 is required for all cases except during a software
upgrade) using
ÒSerial Interface RateÓ on page 54
.
Echoed AT commands from the CTA 500
dm do not appear
correctly on your PC, but the response messages appear
correctly.
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Check the echo option on your PC.
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Disable echo if your PC displays duplicate characters. Enable
echo if your PC does not display any characters.
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See
ÒSet Local EchoÓ on page 38
for more information.
AT response messages do not appear correctly on your PC but
AT commands appear correctly.
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If numbers are being returned to the PC instead of messages,
change the message code setting on the CTA 500
dm
. See
ÒVerbose ControlÓ on page 40
for more information. The
numeric responses and indications are shown in
ÒNumeric
CTA 500dm responsesÓ on page 83
.
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Make sure that your terminal is operating in full duplex mode
rather than half duplex mode.