Online Operation; Misc Operation - Paradyne COMSPHERE 3920Plus Technical Reference Manual

Symptom
Intermittent disconnects, high error
rates, or excessive retransmissions
occur.
The modem establishes and then
disconnects the call.
High error rates occur when running
a local loopback or self-test.
Symptom
The data is scrambled.
Data is missing during a transfer.
Symptom
Problems in collecting Health and
Status information from tributary
modems.
3920-A2-GH30-40
Table B-5
(2 of 2)
Modem — VF Connection
Perform an End-to-End test. Refer to
You may have a poor VF connection. Try dialing again.
The remote modem may have encountered an error control (EC) disconnect. If
the modems cannot negotiate EC, then a disconnect occurs.
The remote modem may be in a forced Error Control mode (disconnect if there
is no error control). Reconfigure your modem to V.42/MNP or Buffer and try
again.
Check the LCD to determine the reason for the disconnect.
Perform a Local Analog Loopback test.
Incoming rings can cause data errors during a loopback test. Abort the test,
disconnect the modular VF cord, and restart the test.
Table B-6

Online Operation

Verify that the character format (data bits, parity, and stop bits) is set to the
same value in both modems.
Verify that you are using the same method of flow control for both the modem
and the DTE.
If using XON/XOFF flow control, verify that the modem's parity matches the
DTE's parity.
Table B-7

Misc Operation

When a multipoint network contains tributary modems using different firmware
releases, you could encounter problems in the collection of Health and Status
information. If the above situation applies to your network, set the Mixed Trib
F/W configuration option to Yes.
October 1998
Action
Pattern located in Chapter 8, Test Branch.
Action
Action
Troubleshooting
B-5