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Creating a command statement: at, Command statement guidelines, Monitor display – Northern UTA220/UTA220k User Manual

Page 66: Dte character echo: e, Command statement buffer

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UTA220/UTA220k

AT Command Operation

CREATING A COMMAND STATEMENT: AT

To create a command statement, use the following steps:

1. Type AT, the attention code telling the unit a command
statement follows.

2. Type the command.

3. Press the return key to “Enter” or send the command
statement to the TA.

An example of a command statement using the dial command
(D) follows.

ATD555-1212

This statement can be read as: Attention: dial 555-1212.

Another example: Enter ATZ. This means “Attention: reset the
TA and reload current configuration with stored values.”

After entering a command line the TA returns a response
message indicating whether the command was accepted, or by
giving the data requested by the command line.

The AT command also sets some of the TA’s DTE data
parameters, such as DTE speed, parity, and bits per character
to match the DTE. This process is repeated each time the AT
prefix is typed.

COMMAND STATEMENT GUIDELINES

When typing command statements, the following rules apply:

• Return must be pressed to execute (Enter) a command.

• The command buffer can hold 128 characters including

spaces.

• Use the backspace or delete key to erase the last character.

MONITOR DISPLAY

As commands are typed they normally appear on the DTE
monitor. This is called local character echo.

DTE CHARACTER ECHO: E

To determine if echo is set properly, type AT. If the terminal
displays AT, echo is set correctly. If it displays AATT, then
echo should be disabled by typing ATE. If the terminal does
not display the AT at all, echo should be enabled by typing
ATE1. The echo option only affects command mode operation.

COMMAND STATEMENT BUFFER

The TA temporarily stores up to 128 characters in a memory
buffer. If more than 128 characters are entered before the end-
of-line characters, the TA ceases to echo and waits for the end
of line character. To correct this condition, retype the com-
mand using 128 characters or less.