Recovering At Commands - Paradyne COMSPHERE 3830 Quick Reference

Recovering AT Commands

AT commands are issued from asynchronous terminals and personal computers.
Certain dialing methods, such as V.25bis and synchronous operation, disable the use
of AT commands and place the modem into a state known as Dumb mode. The
Model 3830 is capable of normal operation when in Dumb mode. However, if the setting
of a configuration option must be changed, it can only be accomplished using an AT
command.
The AT Recovery command (AT***) places the modem into a temporary state that
restores AT commands. When in this state, the modem's previous settings are retained
except for the following configuration options:
H
The DTE Dialer Type configuration option (&M and &Q) is set to AT
H
The Async/Sync Mode configuration option (&M and &Q) is set to Async
H
The DSR Control configuration option (&S) is set to Forced On
H
The LSD Control configuration option (&C) is set to Forced On
If these settings are not appropriate, then change them to a setting compatible with
your current application.
The procedures for an AT recovery using an asynchronous terminal or personal
computer are listed in the following section. Read through these procedures before
performing a recovery:
"
Procedure
1. Turn the modem Off and then ON. The modem performs a power-up self-test in
which all LEDs light. While this is running, repeatedly press the A key of your
DTE's keyboard (or keep the key depressed if your keyboard automatically repeats
characters that way). Keep doing this until A's (or a's) appear on your DTE screen.
(You may use all uppercase or all lowercase characters.)
At least three consecutive A's must be entered within a 2-second time interval.
If these characters are not echoed back to the DTE screen after the power-up
self-test is complete, then the modem is still in Dumb mode and maintains its
current configuration. Turn the modem Off and then ON again, and repeat Step 1.
2. Once the characters are echoed back to the DTE,
Type: T***
(The case of this character must be consistent with the case used in Step 1. Mixed
case prefixes such as aT or At are not recognized.)
This must be entered within 10 seconds after receiving the echoed characters.
Press: Enter
The screen displays OK.
The modem is now in AT Recovery mode, and remains in this state until a Save or
power reset occurs. While in this mode, you can use AT commands to make any
necessary changes to configuration options.
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