This appendix contains an alphabetic listing of the AT commands
to which the modem will respond. Default settings are bold.
Command
|
Function |
$
|
Display help for the Basic command set. |
+++
|
Escape code. Once your modem is online with another
device, the only command it recognises is an escape code of three
typed plus signs, which forces the modem back to Command mode. Do
the following when issuing the command:
1 Wait 1 second after sending the last item of data.
2 Type +++
3 Wait 1 second before typing any data.
When you type +++, the modem will either hang up or stay on line,
depending on how you set S14. |
>
|
Repeat command. If you include the repeat command in the Dial string,
the modem will dial the number and wait 60 seconds for a carrier.
If the line is busy, the modem will pause for 2 seconds and then
redial. The modem makes a maximum of 10 attempts.
|
A/
|
Reexecute the last-issued command. DO NOT type AT or
press Enter. |
A>
|
Repeat the last-issued command until canceled by pressing
any key. DO NOT type AT or press Enter. |
AT
|
Attention prefix: informs a modem that a command is
coming. AT must precede all commands except A/, A>, and +++. |
A
|
Force a modem to answer when it is not receiving an
incoming call. |
Bn
|
Set handshaking options. |
|
B0
|
ITU-T V.25 answer sequence; required to answer all V.34-type
and overseas calls. |
B1
|
Bell answer tone. This setting selects HST modulation,
but use it only if the modem is not required to answer V.34-type calls. |
Cn
|
Enable or disable the transmitter.
|
|
C0
|
Transmitter disabled; for receiving only. |
C1
|
Transmitter enabled. |
With the exception of the Dial options, ANT commands
issued at modems ignore any commands issued after D in the same
command string.
|
Dn
|
Dial a phone number and issue other optional commands.
The numbers 0-9 are accepted. The maximum number of characters allowed
is 36, including the AT prefix, punctuation, and spaces.
|
Optional parameters: |
|
P
|
Dial using pulses. |
T
|
Dial using tones. |
,
|
(Comma) Pause for 2 seconds (or the time in S-Register
8). |
;
|
(Semicolon) Remain in Command mode after dialing. |
"
|
Dial the letters that follow. Example, Atdt 1.800 dial
USR same as Atdt 18002425877; a second switched out of
quote mode. |
W
|
Wait for a second dial tone before continuing to dial
(with X3 or higher). |
@
|
Wait for an answer (with X3, X4, or X7). |
/
|
Pause for 125 milliseconds. |
R
|
Reverse frequencies. Use this command when calling an
originate-only modem. It forces the modem to dial out at the answer
frequency. |
!
|
Flash the switchhook (off hook 0.5 seconds, on hook
0.5 seconds, then off hook). Use ! when other modems share the line. |
L?
|
Display the last-dialed number. |
L
|
Dial the last-dialed number. |
Sn
|
Dial the number stored in memory at position n, where
n = 0-9. Store the number in memory using the &Z command. |
$
|
Display help for the dial commands. AT D$ |
En
|
Command mode echo. Enables or disables the display of
your typed commands. |
|
E0
|
Command mode echo OFF. Your typing will not appear on
the screen. |
E1
|
Command mode echo ON. Your typing will appear on the
screen. |
If double characters appear on the screen, both
the modem's local echo and your software's local echo are on.
|
Fn
|
Online local echo. If ON, a modem displays
on your screen the data that it is transmitting to another modem. |
|
F0
|
Online echo ON. (Sometimes called half duplex.) |
F1
|
Online echo OFF. (Sometimes called full duplex.) |
Hn
|
Go on or off hook. |
|
H0
|
Go on hook (hang up). |
H1
|
Go off hook (pick up) |
In
|
Query the modem. |
|
I3
|
Displays the banner (product name). |
I4
|
Display current modem settings. |
I5
|
Display settings stored in NVRAM. |
I6
|
Display statistics for the last call. |
I7
|
Display product configuration. |
I8
|
Lists phone numbers with redial restrictions. |
I9
|
Displays modems Plug and Play ID. |
I10
|
Display dial security account status information. |
I11
|
Display connection report (contains symbol rates). |
I15
|
Display caller ID information. |
I16
|
Display connection report. |
I17
|
Display connection report. |
Kn
|
Control the modem clock. ATI6 displays the time. |
|
K0
|
If online, display current call duration. If offline,
display last calls duration. |
K1
|
Display the actual time. Set the clock using ATI3=HH:MM:SS
K1. |
Ln
|
Internal modems only: Controls the speakers volume.
|
|
L0
|
Quietest |
L1
|
Low |
L2
|
Medium |
L3
|
Loudest |
Mn
|
Control when the speaker sounds |
|
M0
|
The speaker is always off. |
M1
|
The speaker is on until the call is negotiated. |
M2
|
The speaker is always on. |
M3
|
The speaker turns on after the last digit is dialed
and stays on until the call is negotiated.
|
On
|
Return online. Use with the escape code (+++) to toggle
between command and online modes. |
|
O0
|
Return online (normal). |
O1
|
Return online and retrain. Use O1 if there were errors
in a non-ARQ data transfer. |
Qn
|
Enable or disable the display of result codes. |
|
Q0
|
Display result codes. |
Q1
|
Suppress result codes (quiet). |
Q1
|
Suppress result codes when answering. |
S$
|
Display help screens for the S-Registers. |
Sr=n
|
Set S-Register value: r is any S-Register; n must be a decimal number
between 0 and 255. |
Sr.b=n
|
Set a bit-mapped register: r is the S-register, b is
the bit, and n is 0 (off) or 1 (on). |
Sr?
|
Query contents of S-register r. |
Refer to the S-Registers chapter of the Appendixes section for
a listing of all the S-Registers. |
Vn
|
Display result codes in words or numbers. |
|
V0
|
Display result codes in numeric form. |
V1
|
Display result codes in verbal form. |
Xn
|
Control the amount of information displayed in the result codes.
The default is X7 (all codes except 12/VOICE). The modem doesnt
try to detect signals if it isnt set to report them.
For result codes in synchronous operations,
refer to the Dedicated/Lease Line and Synchronous Applications chapter
of the Contents section. For more detailed information, refer to
the Result Code Meanings and Sets chapter of the Appendices
section.
|
|
X3
|
Ignore Dial Tone |
X4
|
Microsoft default |
X7
|
Courier 56K Corporate modem default |
Z
|
Software reset. If DIP Switch 1 is ON (factory setting),
revert to the settings in NVRAM. If DIP switch 1 is OFF, reset to
the &F0 configuration template (no flow control). |
Z!
|
Complete hardware reset |
Command
|
Function
|
&$
|
Display help for the ampersand (&) command
set. |
&An
|
Enable or disable the display of additional result code
subsets. (Also, see the Xn command.) |
|
&A0
|
Do not display ARQ result codes. |
&A1
|
Display ARQ result codes. |
&A2
|
In addition to ARQ result codes, display HST, V.32,
V.FC, V.34, or DIGITAL modulation indicator. |
&A3
|
In addition to ARQ and modulation indicators, display
an error control indicator (LAPM, HST, MNP, SYNC, V.120, or NONE)
and a data compression type (V42 bis or MNP5).
|
&Bn
|
Set the serial port rate to variable or fixed. |
|
&B0
|
Variable: The serial port rate adapts to match the speed
of the connection. |
&B1
|
Fixed: The modem always communicates with your computer
at the rate at which you have set, regardless of the connection rate.
|
&B2
|
When answering calls, use the fixed rate for ARQ calls
and variable rates for non-ARQ calls. |
The serial port rate should be equal to or higher
than the &Nn rate.
|
&Cn
|
Controls how the modem sends a Carrier Detect (CD) signal to your
computer. |
|
&C0
|
CD always ON, even if the modem is not online. |
&C1
|
Normal operations. The modem sends a CD signal when
it connects with another modem and drops the CD when it disconnects. |
&Dn
|
Control how the modem responds to Data Terminal Ready (DTR) signals. |
|
&D0
|
DTR is always ON (ignored). |
&D1
|
If issued before connecting with another device, the Courier 56K Corporate
modem can enter online Command mode during a call by dropping DTR.
&D1 functions similarly to the escape code (+++).
Return online with the On command, or hang up with the Hn command.
|
&D2
|
Normal DTR operations. The modem will not accept commands
unless your computer sends a DTR signal. Dropping DTR ends a call. |
&D3
|
Modem resets with DTR toggle. |
&Fn
|
Load one of the three configuration templates that are stored permanently
in read-only memory. Refer to the Flow Control Template chapter
of the Appendixes section for the settings for each template.
To load a template into current memory, enter AT&Fn. To write
a template to NVRAM, enter AT&Fn&W.
If DIP switch 1 is OFF, &F0 is always loaded into memory at
power-on or reset.
|
|
&F0
|
Load No Flow Control template settings. |
&F1
|
Load Hardware Flow Control template settings. |
&F2
|
Load Software Flow Control template settings. |
&Gn
|
Set guard tones for international calls. |
|
&G0
|
No guard tone. Use this in the United States and Canada. |
&G1
|
This sets a 550 Hz guard tone, and is used in some European
countries. |
&G2
|
This sets an 1800 Hz guard tone, and is used in the
U.K. and some Commonwealth countries. &G2 requires the B0 setting. |
&Hn
|
Transmit data flow control. Prevents the modems
buffer for data transmitted to the modem by its attached computer
from overflowing. |
|
&H0
|
Disable transmit data flow control. |
&H1
|
Use hardware flow control. Requires that your computer
and software support Clear to Send (CTS) at the EIA-232 interface. |
&H2
|
Use software flow control. Requires that your software
support XON/XOFF signaling |
&H3
|
Use both hardware and software flow control. If you
are unsure about what your equipment supports, select this option.
|
&In
|
Received data software flow (XON/OFF) control. |
|
&I0
|
Disables XON/XOFF flow control of received data. |
&I1
|
The modem acts on your typed XON/XOFF commands, Ctrl-S
or Ctrl-Q, and passes them to the remote device. |
&I2
|
The modem acts on your XON/XOFF commands, but removes
them from the data stream instead of passing them to the remote device.
This is the recommended setting for ARQ mode. |
&I3
|
Hewlett Packard-Host mode. Applies only to modems attached
to an HP mainframe that uses the ENQ/ACK protocol. Use in ARQ mode
only. |
&I4
|
Hewlett Packard-Terminal mode. Applies only to modems attached to
terminals in an HP system that uses the ENQ/ACK protocol. Use in ARQ
mode only. |
&I5
|
This setting is designed to enable flow control on the
phone link when the connection is not under error control. For this
to work, the remote device must have &I5 capability. |
&Kn
|
Enable or disable data compression. |
|
&K0
|
Disable data compression. |
&K1
|
Use auto-enable/disable. The modem enables compression
if the serial port rate is fixed (&B1) and disables compression
if the serial port rate follows the connection rate (&B0) because
compression offers no throughput advantage when the serial port and
connection rates are equal; in fact, compression may degrade throughput.
|
&K2
|
Always enable data compression. |
&K3
|
Selective data compression. The modem negotiates only
for V.42 bis compression, and disables MNP Level 5 (MNP5) compression.
Use this setting to transfer compressed files. |
&Ln
|
Line type. |
|
&L0
|
Normal. |
&L1
|
Dedicated or leased line. This refers to a special kind
of phone line (at extra cost); not just a phone used only for a modem.
|
&Mn
|
Enable ARQ (error control) or synchronous protocols.
Both your modem and the remote device must use the same protocol.
|
|
&M0
|
Normal mode, no error control. Due to the nature of
phone line channels, this is never recommended for calls above 2400
bps. |
&M1
|
Use for online synchronous mode without V.25 bis. This
setting is exclusive of the modems' error control. |
&M4
|
Normal/ARQ mode. If an ARQ connection isn't made, the
modem operates in Normal mode as though it were set to &M0. |
&M5
|
ARQ asynchronous mode. The modem hangs up if an ARQ
connection cannot be made. |
&M6
|
V.25 bis synchronous mode using a character-oriented
link protocol similar to BISYNC. |
&M7
|
V.25 bis synchronous mode using the HDLC link protocol.
|
&Nn
|
Sets fixed link speed. |
&Nn&UN
|
Sets highest and lowest link speeds |
|
N=0
|
Variable rate. The modem negotiates with the remote
device for the highest possible connection rate, depending on the
capabilities of the remote device. |
n=1-38
|
Fixed rate. The modem connects only if the remote device is operating
at the same rate. You can use this feature to filter out calls at
other than a specific rate for security or other reasons.
The connection rate should be lower than or equal to the serial
port rate.
|
|
n=1
|
300 bps |
n=2
|
1200 bps |
n=3
|
2400 bps |
n=4
|
4800 bps |
n=5
|
7200 bps |
n=6
|
9600 bps |
n=7
|
12000 bps |
n=8
|
14400 bps |
n=9
|
16800 bps |
n=10
|
19200 bps |
n=11
|
21600 bps |
n=12
|
24000 bps |
n=13
|
26400 bps |
n=14
|
28800 bps |
n=15
|
31200 bps |
n=16
|
33600 bps |
n=17
|
28000 bps |
n=18
|
29333 bps |
n=19
|
30666 bps |
n=20
|
32000 bps |
n=21
|
33333 bps |
n=22
|
34666 bps |
n=23
|
36000 bps |
n=24
|
37333 bps |
n=25
|
38666 bps |
n=26
|
40000 bps |
n=27
|
41333 bps |
n=28
|
42666 bps |
n=29
|
44000 bps |
n=30
|
45333 bps |
n=31
|
46666 bps |
n=32
|
48000 bps |
n=33
|
49333 bps |
n=34
|
50666 bps |
n=35
|
52000 bps |
n=36
|
53333 bps |
n=37
|
54666 bps |
n=38
|
56000 bps |
&Rn
|
Received data (RTS) hardware flow control. |
|
&R0
|
Delay Clear to Send (CTS) response after Request to
Send (RTS). |
&R1
|
Ignore RTS. This setting is required if your computer
or terminal or software does not support RTS. |
&R2
|
Enable hardware flow control of received data. The modem
sends data to the computer only upon receipt of the RTS signal. |
&Sn
|
Send the computer a Data Set Ready (DSR) signal via
the EIA-232 interface. |
|
&S0
|
DSR is always ON (override). |
&S1
|
In Originate mode: Send DSR after dialing, on detection
of the remote devices answer tone. In Answer mode: Send DSR
after sending an answer tone. |
&S2
|
When Carrier is lost, send a pulsed DSR signal with
Clear to Send (CTS) following Carrier Detect (CD). This option is
for specialised equipment such as automatic callback units. |
&S3
|
Same as &S2, but without the CTS signal. |
&S4
|
Send the computer DSR at the same time as CD. |
&S5
|
Send DSR normally, and follow CTS with CD. |
&Tn
|
Test the modem. |
|
&T0
|
End testing. |
&T1
|
Local digital loopback |
&T2
|
Local analogue loopback |
&T3
|
Not used (error) |
&T4
|
Grant Remote Digital Loopback request |
&T5
|
Deny Remote Digital Loopback request |
&T6
|
Request Remote Digital Loopback |
&T7
|
Not used (error) |
&T8
|
Local digital loopback with test pattern |
&T9
|
Local analogue loopback with test pattern |
&Wn
|
Write the current settings to NVRAM. |
&Xn
|
External modems only: Designate the source of synchronous
transmit clock timing signals. |
|
&X0
|
The Courier 56K Corporate modem sends transmit clock
timing signals to the DTE over the serial interface. DTE rate follows
the connection rate. |
&X1
|
The DTE sends transmit clock timing signals to the modem
over the serial interface. Typical use: multiplexed leased lines. |
&X2
|
The Courier 56K Corporate modem sends receiver clock
timing signals, which are looped to the transmit clock and sent to
the DTE over the serial interface. Typical Use: Systems that require
synchronisation of data flowing in both directions. |
&Yn
|
Break handling. This command lets you send a break to
stop data transfer without disconnecting. |
|
&Y0
|
Destructive, don't send break. |
&Y1
|
Destructive, expedited. |
&Y2
|
Nondestructive, expedited. |
&Y3
|
Nondestructive, unexpedited; the modem sends a break-in-sequence
with data received from your computer or terminal. |
If the call is under data compression, destructive
breaks cause both modems to reset their data compression tables.
When transmission resumes, the modems build new tables, and the
result is temporary lower-than- normal throughput.
|
&Zn=s
|
Store up to 10 numbers in NVRAM, where n is the position 0-9 in
NVRAM, and s is the phone number string. The number string may be
up to 36 characters long, including any Dial command options.
Example: AT&Z2=555-6789
In the following example, &M0 (no error control) is inserted
before the Dial command: AT&M0 DS2
|
This command functions differently when Dial
Security is enabled.
Also, do not include modem settings in the &Zn string. If the
call requires a special setting, insert it in the command string
before the DSn command.
|
&Zn=L
|
Stores the last-dialed number in position n. |
&Zn?
|
Display the phone number stored in NVRAM at position
n (where n = 0-9). |
&ZC=s
|
Store command string s in NVRAM. The command string
can be up to 30 characters long; spaced do not count. This command
is used so you can call another modem without loading your communications
software. |
&ZC?
|
Display the stored command string. |
Command
|
Function |
%$
|
Display the help panels for the percent (%) command
set. |
%An
|
Create and configure security accounts. |
%Bn
|
Remotely configure a modem's serial port rate. |
|
%B0
|
110 bps |
|
%B1
|
300 bps |
|
%B2
|
600 bps |
|
%B3
|
1200 bps |
|
%B4
|
2400 bps |
|
%B5
|
4800 bps |
|
%B6
|
9600 bps |
|
%B7
|
19200 bps |
|
%B8
|
38400 bps |
|
%B9
|
57600 bps |
|
%B10
|
115200 bps |
%Cn
|
Remote configuration control. |
|
%C0
|
Defer configuration changes until the call is ended.
Changes take effect for ensuing connections. |
|
%C1
|
Cancel configuration changes and restore the original
configuration.
|
Using%C1 will not reverse any changes that you
wrote to NVRAM (with &W) or forced (with%C2).
|
|
%C2
|
Force configuration changes to take effect immediately.
|
We recommend against forcing configuration changes
unless it is absolutely necessary. An unreliable connection, or
loss of connection, may result.
|
%D=
|
Set a DTMF password. |
%E=n
|
Erase security settings. |
|
%E=1
|
Erase local-access password. |
|
%E=2
|
Erase Autopass password. |
|
%E=3
|
Erase passwords in accounts 0-9. |
|
%E=4
|
Erase phone numbers in accounts 0-9. |
|
%E=5
|
Disable Account, Dialback, and New Number fields in
accounts 0-9. |
%Fn
|
Remotely configure another devices data format.
|
|
%F0
|
No parity, 8 data bits. |
|
%F1
|
Mark parity, 7 data bits. |
|
%F2
|
Odd parity, 7 data bits. |
|
%F3
|
Even parity, 7 data bits. |
%L=
|
Set a local-access password. |
%Nn
|
Set the offline clock speed for synchronous mode. |
|
%N0
|
Reserved |
|
%N1
|
Reserved |
|
%N2
|
1200 bps |
|
%N3
|
2400 bps |
|
%N4
|
4800 bps |
|
%N5
|
7200 bps |
|
%N6
|
9600 bps |
|
%N7
|
12000 bps |
|
%N8
|
14400 bps |
|
%N9
|
16800 bps |
|
%N10
|
19200 bps |
%Pn=
|
Disable password security (n=0 or n=1) when no character
follows the equal sign. |
%Pn=s
|
Set the following password (s) for viewing privileges
only (n = 0), or view and configuration privileges (n= 1). |
%Pn?
|
Display password n. |
%S=n
|
Access the security accounts. Does not disable
security. |
%T
|
Enable the recognition of tone frequencies of analogue dialing
devices.%T is meant primarily for use with network applications,
but may also be integrated into certain software programs. For example,
%T could be used in a security program to identify incoming tone
security codes.
To return the modem to Command mode, press any key or drop the
computer's or terminal's DTR signal. The modem responds OK.
|
%V=PWn
|
Assign the password in account n in your modems
security account as your Autopass password |