4 AT Commands, S-Registers, and Result Codes
37
Command: &T
n
V.54 Test Commands
Values: n = 0, 1, 3 or 6
Default: None
Description: &T0 Abort. Stop any test in progress.
&T1 Local analog loopback test.
&T3 Local digital loopback test.
&T6 Remote digital loopback test.
Note: To stop a test, you must use the escape sequence (+++AT) before typing
AT&T0.
Command: &V Display Current Settings
Values: n/a
Description: Displays the active modem settings, including the callback se-
curity settings if callback security is enabled. If the setup pass-
word has been entered, it also displays the callback security
passwords.
Command: &W
n
Store Current Configuration
Values: n = 0
Default: None
Description: &W0 Stores current modem settings in nonvolatile memory and
causes them to be loaded at power-on or following the ATZ
command instead of the factory defaults. See also the &F com-
mand.
&W1 Clears user default settings from nonvolatile memory and
causes the factory defaults to be loaded at power-on or follow-
ing the ATZ command.
Command: &Y
n
Select Stored Configuration for Hard Reset
Values: n = 0
Default: 0
Description: &Y0 Select stored configuration 0 on power-up. (For backward
compatibility with some software.)
&Y1 Not supported—responds ERROR.
Command: &Zy
=x
Store Dialing Command
Values: y = 0–3 (callback security disabled) or 0–29 (callback security
enabled)
x = Dialing command
Default: None
Description: Stores dialing command x in memory location y. Dial the
stored number using the command ATDS=y. See also the
#CBSn command. For callback security options, see Chapter 6.
Command: &&S Speaker Codec Loopback
Values: n/a
Description: Provides a loopback from the microphone to the speaker. For
testing and debugging only.