COMSPHERE 3825Plus Modem
B-2
November 1996
3825-A2-GB30-20
Table B-2
Online Operation
Symptom
Action
Data scrambled or
unreadable
Verify that the character format (data bits, parity, and stop bits) is set to the same value in
both modems.
Missing data during a
transfer
Verify that you are using the same method of flow control for both the modem and the DTE.
transfer
If using XON/XOFF flow control, verify that the modem’s parity matches the DTE’s parity.
Table B-3
Leased-Line Operation
Symptom
Action
Modems do not train-up on
leased lines
Verify that the correct cabling is used for your application. Refer to Chapter 2 for modem
installation instructions.
Verify that one modem is configured for Answer mode and the other is configured for
Originate mode.
Table B-4
(1 of 3)
Modem – VF Connection
Symptom
Action
Modem does not receive a
dial tone
Attach the telephone directly to the wall outlet to verify that a dial tone exists.
Make sure the VF line is connected to the modem’s rear jack labeled LINE.
Modem does not go
off-hook and answer an
incoming call
Verify that the Auto-Answer Ring Count configuration option (S-register 0) is set to a value
other than 0 (disable).
incoming call
Verify that the DTE is providing DTR to the modem.
If the DTE does not provide DTR to the modem, verify that the modem’s &D command
(DTR Action configuration option) is set for Ignore (&D0).
Verify that all cables are attached to the correct connectors on the rear of the modem.
Modem goes off-hook,
answers, but does not
connect
Perform a Local Analog Loopback test and verify that data entered at the DTE is echoed
back to the DTE.
connect
Verify that the originating modem is compatible.
Verify that originating modem recognizes your modem’s answer tone.
