Paradyne COMSPHERE 3830 Documentation Update

Update to COMSPHERE 3800 Series Modems
Model 3830 User's Guide (3830-A2-GB91-00)
Document No. 3830-A2-GB41-00
July 1994
The COMSPHERE 3800 Series Modems,
Model 3830, User's Guide (3830-A2-GB91-00)
inaccurately describes the AT command recovery
process. The corrected information in this update sheet
will be incorporated into future releases of the User's
Guide. In the meantime, keep this document with your
User's Guide.

Recovering AT Commands

AT commands are issued from asynchronous
terminals and personal computers. Certain dialing
methods, such as V.25 bis 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:
The DTE Dialer Type configuration option (&M
and &Q) is set to AT
The Async/Sync Mode configuration option (&M
and &Q) is set to Async
The DSR Control configuration option (&S) is set
to Forced On
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:
1. Turn the modem Off and then ON. The modem
performs a power-up self-test in which all
TM
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.
Keep in mind that the &C command is changed
to Forced On (&C0), the &M and &Q
commands are changed to Async mode with AT
commands enabled (&M0 and &Q0), and the
&S command is changed to Forced On (&S0). If
these settings are not appropriate, then reset
them to a desired choice before exiting AT
Recovery mode.
3. To save changes, use the &W command:
TYPE: AT&Wn
Where: n is one of the following storage areas:
0 for Active (Saved)
1 for Customer 1
2 for Customer 2
PRESS: Enter
The modem exits AT Recovery mode and
returns to its previous application environment.