Appendix a: at command set – Windows Marketplace V.90 User Manual

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Appendix A: AT Command Set

AT Commands

AT commands are issued to the modem to control the modem’s operation and

software configuration. AT commands can only be entered while the modem is in

command mode. The format for entering AT commands is:

TYPE:

ATXn

where X is the AT command, and n is the specific value for that command.

PRESS:

Enter

Any command issued is acknowledged with a response in text format known as

result codes. For multiple AT commands in the same command line, the com-

mands are executed in the order received from the DTE. Should execution of a

command result in an error, or a character not be recognized as a valid command,

execution is terminated, the remainder of the command line is ignored, and the

ERROR result code is issued. Otherwise, if all commands execute correctly, only

the result code associated with the last command shall be issued; result codes for

preceding commands are suppressed.

In the following listing, all commands and command values accepted by the mo-

dem are shown; any entries other than those shown cause the ERROR result code.

+++

Escape sequence

The escape sequence allows the modem to exit data mode and enter on-line com-

mand mode. While in on-line command mode, you may communicate directly to

your modem using AT commands. Once you are finished, you may return to data

mode using the ATO command. A pause, the length of which is set by the Escape

Guard Time (S12), must be used after an escape sequence is issued. This pause

prevents the modem from interpreting the escape sequence as data. The value of

the escape sequence character may be changed using Register S2.

A/

Repeat Last Command

This command repeats the last command string entered. Do not precede this com-

mand with an AT prefix or conclude it by pressing Enter.

A

Answer Command

This command instructs the modem to go off-hook and answer an incoming call.

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