Nortel Networks CTA 500dm - Manual (Page 73)

Troubleshooting 73
P0873832 Issue 05 CTA 500 dm On Line Guide
AT commands do not appear.
¥
To see the commands that you type in a HyperTerminal window,
you must Disconnect, then Connect again.
Using HyperTerminal, the message “Unable to open COMx
port” appears.
¥
The CTA 500dm may be in use by another application (for
instance, Dial-Up Networking).
Data call problem?
Data calls are not answered automatically.
¥
Make sure that rings until answer S0 is not set to 0. See ÒS-
registersÓ on page 41 for more information.
¥ If the rings until answer value is too high, the calling device may
time out.
Data calls are answered but are terminated too soon.
¥
Make sure that you are calling the correct device.
¥ Make sure that the remote device is set to the same rate
adaptation protocol as the CTA 500dm. See
ÒRate adaptation
protocol speciÞcationsÓ on page 80 for more information.
¥ Make sure that the proper authentication protocols are used at
both ends and that your ID and password are correct.
¥ If the data rate is set to 64 kbit/s, the network may not be able to
support 64 kbit/s. Try connecting at 56 kbit/s. See
ÒOutgoing
Call Control commands summaryÓ on page 47 to change your
data rate.
The CTA 500 dm rejects calls.
¥ Make sure the CTA 500dm is conÞgured to accept calls and that
the call type (bearer capability) and call rate are set correctly. See
ÒIncoming Call Control commands summaryÓ on page 49 for
more information.
¥ ÒAllow caller accessÓ may not be enabled in Installing Dial-Up
Server conÞguration.
The CTA 500 dm aborts calls when dialing.
¥ This may be the any key abort feature of the dial command. See
ÒDial CommandÓ on page 44 for more information.
¥ The CTA 500dm may not be seizing a line. Check that the
correct line pool code or external dial digit is used in Dialing