Historia del Conjunto de Comandos AT

A comienzos de los 80s, una compañía llamada Hayes dio inicio a la
fabricación de su módem (modulador-demodulador) Hayes Smartmodem 1200.
Este era un módem de 1200 baudios por segundo. Al muy poco tiempo se
comenzó a comercializar una nueva tecnología: la de los módems de 2400
baudios. Estos ofrecían el doble de velocidad, y la demanda por el
último modelo de Hayes se evaporó de la noche a la mañana. No era para
menos: los nuevos aparatos reducían a la mitad el tiempo de conexión
telefónica (y su costo).

Si querían siendo relevantes en la industria, Hayes debia completar de
apuro un nuevo modelo.

Los tiempos productivos requeridos no alcanzaban para proponer un nuevo
producto que superase una tecnología ya dominada por su competencia.
Esto obligó incluso a Hayes a dejar de lado cualquier tipo de
consideración para hacer cambios fundamentales o embellecer al nuevo
diseño. Se decantaron por a un producto igual al que tenían, pero que
fuese capaz de ofrecer el doble de velocidad, y que pudiesen
industrializarlo inmediatamente bajo el nombre de Smartmodem 2400.

De esta forma y sin advertirlo Hayes terminó creando la nueva tendencia
de estandarización en módems, una que - increíblemente - que continúa
hasta el día de hoy.

Podríamos decir que la afirmación de que dichos módems eran
"inteligentes" como afirmaba su marca comercial, es estirar un poco a la
realidad... incluso si los comparamos con los módems de aquel entonces.

Lo usual por entonces era que el usuario cumpliese un papel ineludible
para establecer el enlace de comunicación. Debía usar un aparato
de teléfono conectado a la extensión de línea, discar el número deseado
y oír la portadora de respuesta del módem remoto, para luego presionar
un botón "Comienzar", y luego colgar el tubo. Sólo entonces se podía estableecer la conexión de datos.

Este proceso de discado manual era bastante común en los módems
concebidos para ser utilizados con las líneas telefónicas del sistema
público conmutado (PSTN) de comienzos de la década de 1980. Los módems
con autodiscado eran bastante raros, esta la capacidad discar números
telefónicos solía ofrecerse sólo como una opción a costo extra. Por
ejemplo, el módem Radio Shack DC-1200 de 1200 baudios por segundo (un
módem Ventel de 1983) costaba la friolera de U$S 699 de la época, y su
módulo opcional de autodiscado (que sólo podía efectuar el más antiguo
marcado por pulsos en lugar de los más modernos marcado por tonos)
requería desembolsar unos unos U$S 150 adicionales. Incluso una tarea
común como podía ser colgar la llamada requería que el usuario pasara el
módem en estado de espera ("hold") y colgara la línea, o bien apagara el
módem.

Los Smartmodem 1200 y 2400 - por lo pronto - ya eran capaces de discar
por sí mismos. Estaban provistos de un altavoz interno, ya que se
consideró realmente necesario oir los tonos de discado. Aún así, tanto
el Smartmodem 1200 como el Smartmodem 2400 eran realmente incapaces de
reconocer un tono de línea ocupada o bien detectar la presencia del tono
de discado, ni tampoco contaban con ninguna de las docenas de otras
características consideradas estándares en los módems producidos desde
finales de los 80s.

Estos Smartmodems Hayes incluía varias características especiales
(capacidad nativa de transmitir código morse, trabajar como
radioteletipos, y operar con repetidores de radio amateur). Sin embargo,
estas funcionalidades de nicho no generaron interés para la mayoría de
los usuarios, y terminarían desapareciendo en años posteriores,

Lo que terminó haciendo realmente únicos al Smartmodem Hayes 1200 y al
2400 fue la introducción - por vez primera - de la noción que
un fabricante concibiera producir dos modelos diferentes de módems para
el POTS/PSTN que hicieran uso del mismo conjunto de comandos de
operación.

Esto significó que cualquier programa de software que entendía cómo
hacer que un Smartmodem 1200 discara un número telefónico, pudiese
funcionar también con el Smartmodem 2400 sin que tuviese que modificarse.

Como se ha mencionado, esto sucedió más por necesidad y accidente que
por intencionalidad de diseño para poder afrontar la velocidad de 2400
baudios por segundo que demandaban los usuarios.

En ese momento, había muy pocos servicios telemáticos en el mundo, y
Compuserve era un exponente mayor, por mucha diferencia. Toda vez que un
fabricante sacaba un nuevo módem al ruedo, sus compradores solían tener
que aguardar hasta varios meses para que los programadores de las
aplicaciones de software pudiesen escribir un controlador específico que
les permitiese compatibilizar cada nuevo modelo de módem con algunas
determinadas marcas o modelos de computadora, y ésta fuese capaz de
conectarse a Compuserve.

Por tal motivo, para el momento en que el Smartmodem 2400 salió al
mercado, ya existía un controlador operativo para el Smartmodem 2400: se
trataba del controlador para el Smartmodem 1200, que ya estaba
disponible - y para muchas plataformas de computadoras - desde hacía
tiempo. Aquel quien compró al nuevo Smartmodem 2400 no se vio en la
necesidad de aguardar la preparación de un nuevo controlador; podía
utilizar aquél que ya estaba hecho para el Smartmodem 1200. El soporte
especial que había que dar al Smartmodem 2400 no iba más allá de agregar
a la documentación una nota que explicara que el Smartmodem 2400
funcionaba también usando el controlador del Smartmodem 1200.

Los demás fabricantes de módems entendieron rápidamente la ventaja de
hacer nuevos modelos de módems que compartieran el mismo conjunto de
comandos similares a modelos ya existentes, algo que pocos vendedores se
habían molestado en hacer. Incluso había diseñadores de módems
individuales que habían tendido a desarrollar rutinariamente conjuntos
de comandos completamente nuevos y diferentes para cada modelo sucesivos
de módems que creaban. El Smartmodem 1200 y 2400 cesaron esta práctica
industrial, y en meros seis meses, ya eran varios los fabricantes que
ofrecían conjuntos de comandos "compatibles con Hayes" como una opción,
o como la única opción de sus respectivos módems.

Hayes disputó en las cortes con estas compañías por usar la marca
"Hayes" en su literatura de producto y empaque, de forma tal que el
resto de los fabricantes se vieron en la necesidad de describir
colectivamente a sus módems como "Compatibles con el Conjunto de
Comandos AT", y continuaron imitando el conjunto de comandos Hayes. Ya
para 1986 prácticamente habñian desaparecido los módems de consumo que
no contaran - al menos - un modo emulado del conjunto de comandos AT.

Años después, la TIA/EIA introdujo un estándar formal títulado "Data
Transmission Systems and Equipment - Serial Asynchronous Automatic
Dialing and Control" (Sistemas y Equipamiento de Transmisión de Datos,
Discado Automático Asíncrono Serial), también conocido como TIA/EIA-602.

El estándar TIA/EIA-602 era casi idéntico a los comandos de datos
específicos que se podían encontrar en los Smartmodems 1200 y 2400
originales. Naturalmente, para el momento en que el estándar
TIA/EIAA-602 comenzó a aplicarse, los fabricantes de la industria ya
comercializaban módems con corrección de errores, compresión y
velocidades mucho mayores. Ninguna de esas nuevas capacidades (o los
comandos que hacían falta para controlarlas) estaban contempladas en el
estándar TIA/IAE-602 (si bien otros estándares o borradores de
estándares ya existían tanto para los comandos específicos requeridos para operaciones de Fax en los módems que los soportaban, así como comandos específicos para operaciones de voz).

Para cumplimentar con estas nuevas características de los módems, muchos
fabricantes eligieron copiar las extensiones del conjunto de comandos
Hayes original ya existentes - las cuales se habñian integrado al modelo
Hayes Ultra de 14.400 baudios. 

Estas extensiones eran mayormente una creación de Rockwell, quien por
entonces era la principal proveedora de microchips para Hayes por
entonces. 

Aún así, no todos los fabricantes de chipsets para módems siguieron la
práctica de utilizar los comandos extendidos del Ultra al pie de la
letra. Esto terminó provocando ciertas incompatibilidades que se
mantivieron largos años sin resolver al intentar usar los comandos Hayes
más sofisticados. Estas incompatibilidades suelen salir aún a superficie
cuando el fabricante de chipset no es Rockwell o un licenciatario del
código fuente para módems de Rockwell.

Aún así, varios licenciatarios terminaron alterando el código
distribuído por Rockwell, e incluso en algunos casos Rockwell misma
terminó introduciendo incompatibilidades por sí misma.


	========== Hayes AT Commands ==============




AT or at always precedes a command. The modem needs these two letters to
adjust itself to the settings of the PC’s comport. The modem then
switches automatically to the defined baud rate and parity, until the
next command is issued or the modem is turned off. The modem will not
respond to any commands not preceded by an AT.

The modem recognises following formats :

1 or 0 start bits, 7 or 8 data bits, no, odd or even parity and 1 or 2
stop bits.

The commands can be issued at a rate between 300 and 115,000bps. In V.23
mode, the commands are sent at 1,200bps. The modem’s replies are then
sent at 75bps to the PC.

The command interpreter recognizes AT and at, but not At or aT. Both
characters have to be sent in upper- or lowercase and must be sent
directly after one another.

 
+++ Switch from data mode to command mode without dropping the line. A
second before and after this command, no other character may be sent to
the modem, including a <CR>.

A/ Repeat last command, no <CR>

 

ATA Answer incoming call

 

When you want to answer a call manually, you type this command after a
ring has appeared on the screen of your Terminal emulator.

 

 

 

D Dial a telephone number

 

ATDTn After issuing this command, the modem will attempt to establish a
connection and dial the number n.

 

Options to the command D: W Wait for dialtone. When using a PABX this is
used to wait for the second dialtone. Note: not all PABXs give a second
dialing tone. Consider using "@" instead.

@ Wait for silence for 5 seconds.

, Pause for 2 seconds (S8)

! Flash ( on-hook for value in S29 )

; Return to command mode after dialing.

P Pulse dial

T Tone dial

n The telephone number to be dialed

Sn Dial number stored in directory entry &Zn where n=0..19. The selected
number is shown on the screen for verification.

J Perform MNP10 link negotiation at highest supported speed (for this
call only).

L Redial last number.

^ Disable calling tone, this call only.

The call can be aborted at any stage before the connect message appears,
by entering any character except Linefeed.

 

ATE Command echo to host

 

E0 Commands are not echoed

E1 Commands are echoed

 

With this command you can select if the modem should return all the
commands to the screen or not. This is useful to check if all characters
are received by the modem. If characters appear double on the screen,
disable echoing by the modem or by your terminal. The value of ATE can
be written in the RAM of the modem using AT&W.

 

ATFn Select transmission mode/speed

 

F0 Auto mode

F1 V.21 300bps

F3 V.23 75Tx/1200Rx with AT%F1

V.23 1200Tx/75Rx with AT%F2

F4 V.22 1,200bps

F5 V.22bis 2,400bps

F6 V.32bis 4,800bps

F7 V.32bis 7,200bps

F8 V.32bis 9,600bps

F9 V.32bis 12,000bps

F10 V.32bis 14,400bps

 

These commands are not valid for V.34 modems. The equivalent command for
the V.34 modems is +MS, please refer to this command.

 

 

ATH Go on-hook, hang up.

 

H0 Go on-hook ( Hang up )

H1 Go off-hook

 

ATI Identifiers

 

I0 Product code

I1 Pre-computed Checksum

I2 Returns OK

I3 Returns OK

I4 OEM String

I5 - I11 Returns OK

I12 ROM Checksum

I13 RC Version number

I14 Shows Firmware version

I15 Shows selected country

I17 GSM option

I18 Shows Supported GSM Kit (GSM-ready™ only)

 

ATL Speaker volume settings

 

L0 Lowest speaker volume

L1 Low speaker volume

L2 Medium speaker volume

L3 Highest speaker volume

 

With this command the speaker volume can be set.

 

ATM Speaker control

 

M0 Speaker always off

M1 Speaker on until carrier detected

M2 Speaker always on

M3 Speaker on only while answering

 

ATNn Select Auto mode

 

N0 Auto mode disabled

N1 Auto mode enabled

 

This command is not longer valid for the V.34 modems.

 

ATOn Return to data mode

 

O0 Return to data mode from command mode, only if on-line.

O1 Return on-line and initiate retrain (2400bps or higher)

 

ATQn Result codes

 

Q0 Modem returns result codes

Q1 Quiet mode enabled. Modem gives no result codes.

 

If the quiet mode is enabled, the responses from the modem are not sent
to the PC.

 

 

 

ATSn Sets and reads the selected register

 

Sn=x Sets register n to the value x

Sn? Reads the value of register n

 

n is a numeric value, varying between 0 and 255 (depending on the
register).

 

ATVn Result codes in numerical or verbose form

 

V0 Returns the code in numerical form

V1 Full-word result codes

 

ATWn Connect messages formatting

 

W0 DTE rate ( connect rate )

W1 Hayes 4 line format : Carrier, Protocol, Compression, DTE rate

W2 Result code is DCE rate ( carrier rate )

 

ATXn Extended Result codes

 

X1 Ignore dialtone and busy tone

X2 Ignore busy tone

X3 Inner dialtone

X4 Modem recognises dialtone and busy tone

 

X3 and X1 set the modem for Blind Dialing. This option is country
specific, because some countries do not allow blind dialing.

 

ATYn Long Space disconnect

 

Y0 Disable long space disconnect

Y1 Enable long space disconnect

 

If the modems receives after activating this function, a BREAK-signal of
at least 1.6 seconds coming from the remote PC, it will send a
BREAK-signal of 4 seconds back to the remote PC before hanging up the
telephone line.

 

ATZn Resetting the modem

 

Z0 Restore stored profile 0

Z1 Restore stored profile 1

 

If this command is issued to the modem during a connection, the modem
will drop the line. According to the parameter n, the modem will restore
the values stored in the non-volatile RAM (See also &W ).

 

AT&Cn Carrier-detect

 

&C0 DCD is always active

&C1 DCD is active if modem is on-line

 

Data Carrier Detect (DCD) is a hardware signal that notifies the
software that the modem is in communication with another modem. Most
software’s will not start-up properly if the DCD is active. Default is
&C1.

 

 

AT&Dn Data Terminal Ready settings

 

&D0 Modem ignores DTR

&D1 Go to command mode on ON-to-OFF DTR transition.

&D2 Hang up on DTR-drop and go to command mode

&D3 Reset (ATZ) on DTR-drop. Modem hangs up.

AT&F Restore Factory Settings

 

&F0 Use profile 0

&F1 Use profile 1

 

The modem is reset to the default firmware settings. If the modem is
on-line, the command will not be executed.

 

AT&Gn Select guard tone

 

&G0 Disables guard tone

&G1 Disables guard tone

&G2 Selects 1800Hz guard tone

 

This command may not be permitted in some countries.

 

AT&Kn Flow Control

 

&K0 Flow control disabled

&K3 RTS/CTS flow control (Hardware)

&K4 XON/XOFF flow control (Software)

&K5 Transparent XON/XOFF flow control

&K6 RTS/CTS and XON/XOFF flow control

 

Flow control is the use of characters or RS232 signals to start and stop
the flow of data to avoid data loss during buffering. This is extremely
important when the DTE/DCE rate is different from the line speed, e.g.
when data compression is used. The DTE/DCE rate must be higher then the
line speed.

 

RTS/CTS flow control (Hardware flow control)

 

The PC will send data to the modem. The modem will store this data in a
buffer. When this buffer is full, the modem will drop the CTS-line,
telling the PC that it has to stop transmitting data until the signal
raises again. If the RTS-signal is OFF, transmitting data to the PC is
stopped until the signal switches to ON.

 

XON/XOFF flow control (Software flow control)

 

If the modem receives a XON-character (S32) from the PC, it stops
transmitting data to the PC until it receives a XOFF-character (S33).
The process is similar if the PC is sending data to the modem.

 

NOTE : The preferable setting is RTS/CTS flow control

 

AT&Pn Pulse dial make-break

 

&P0 : 61/39 ratio at 10pps

&P1 : 67/33 ratio at 10pps

&P2 : 39/61 ratio at 20pps

&P3 : 33/67 ratio at 20pps

 

Settings may be locked depending on country selection. Default is also
country dependent.

AT&Qn Sync/Async Mode

 

&Q0 : Selects direct async operation.

&Q1 : Selects synchronous connect mode with async off-line command mode.

&Q2 : Selects synchronous connect mode with async off-line command mode and enables DTR dialing.

&Q4 : Selects Autosync™ mode

&Q5 : The modem will try to negotiate an error corrected link.

&Q6 : Selects async operation in normal mode.

 

This command is used to control the connection modes permitted.

 

AT&Rn CTS/RTS option

&R0 : In sync mode, CTS tracks the state of RTS. In async mode, CTS acts according V.25bis handshake.

&R1 : In sync mode CTS is always on. In async mode, CTS will drop only if required by flow control.

 

This selects how the modem controls CTS. CTS operation is modified if
hardware FC is selected ( AT&Kn ).

 

AT&Sn DSR Override

 

&S0 : DSR will remain on at all times.

&S1 : DSR will become active after answer tone has been detected and inactive after the carrier has been lost.

 

This command selects how the modem will control DSR.

 

AT&Tn Test and diagnostics

 

&T0 : Terminates test

&T1 : Initiates local analogue loop back

&T2 : Returns ERROR

&T3 : Initiates local digital loop back

&T4 : Enables digital loop back acknowledgment for remote request.

&T5 : Disables digital loop back acknowledgment for remote request.

&T6 : Requests a remote digital loop back without self test.

&T7 : Requests a remote digital loop back with self test

&T8 : Initiates local analogue loop back with self test.

 

The modem will perform selected test and diagnostic functions according
to the parameter supplied. A test can be run only when in an
asynchronous operation in non-error-correction mode. To terminate a test
in progress, the escape sequence must be entered first, except for
parameters 7 and 8.

 

AT&Vn Display current configuration and stored profiles

 

Reports the current (active) configuration, the stored (user) profiles,
and the first four stored telephone numbers.

 

AT&Wn Store current configuration

 

&W0 : Store current configuration in profile 0

&W1 : Store current configuration in profile 1

 

AT&Xn Select Synchronous Clock Source

 

&X0 : Selects internal timing

&X1 : Selects external timing

&X2 : Selects slave receive timing

 

Selects the source of the transmit clock for the synchronous mode of
operation.

 

AT&Yn Designate a default reset profile

 

&Y0 : The modem will use profile 0

&Y1 : The modem will use profile 1

 

Selects which user profile will be used after a hard reset.

 

AT&Zn Store telephone number

 

&Zn=x n=0 to 3 and x=dial string

 

AT%En LQM and Auto-retrain or FB/FF

 

%E0 : Disable Line Quality Monitor and auto-retrain

%E1 : Enable Line Quality Monitor and auto-retrain

%E2 : Enable Line Quality Monitor and fall back/fall forward. (V.34 only)

 

Controls whether or not the modem will automatically monitor the line
quality and request a retrain or fall back / fall forward depending on
the line quality.

 

AT%Cn Enable/Disable data compression

 

%C0 : Disables data compression

%C1 : Enables MNP5

%C2 : Enables V.42bis

%C3 : Enables both V.42bis and MNP5 data compression.

 

Enables or disables data compression negotiation. The modem can only
perform data compression on an error corrected link.

 

AT\Gn Modem to modem flow control

 

\G0 : Disables modem-to-modem flow control

\G1 : Enables modem-to-modem flow control

 

In non-error correction mode, the modem enables or disables the
generation or recognition of modem to modem XON/XOFF flow control
according to the parameter supplied. In error correction mode, the
setting of \G is ignored.

 

AT\Nn Operating mode

 

\N0 : Normal speed buffered mode. (&Q6)

\N1 : Serial interface selected. (&Q0)

\N2 : Reliable connection ( First V.42 the MNP4). Failure to make a reliable connection results in modem hanging up.

\N3 : Auto reliable mode ( First V.42, then MNP4 then speed buffered )

\N4 : V.42 (LAPM) . If connection fails, modem hangs up.

\N5 : MNP4 EC mode. Failure results in hanging up.

 

This command controls the preferred error correcting mode to be
negotiated in a subsequent data connection.

 

\An Select maximum MNP block size

 

\A0 64 characters

\A1 128 characters

\A2 192 characters

\A3 256 characters

 

)Mn Enable cellular power level adjustment

 

)M0 : Disables transmit power level adjustment during MNP10 link negotiation.

)M1 : Enables transmit power level adjustment during MNP10 link
negotiation.

V.34 : Uses the @Mn value to establish initial cellular connection.
After connection power level is determined by modem.

)M2 : Enables transmit power level adjustment during MNP10 link
negotiation. Uses the @Mn value to establish initial cellular
connection. After connection power level is fixed. (V.34 only)

 

Enables or disables automatic adjustment of the transmit power level to
accommodate the signaling requirements of cellular telephone equipment.

 

-Kn MNP Extended Services

 

-K0 Disables V.42 LAPM to MNP10 conversion

-K1 Enables V.42 LAPM to MNP10 conversion

-K2 Enables V.42 LAPM to MNP10 conversion, inhibits MNP ES initiation
during V.42 LAPM answering mode detection Phase (V.34 only)

 

Enables or disables conversion of a V.42 connection to a MNP10
connection.

 

V.34 Commands

Following commands are valid only for the V.34 modems.

 

@Mn Initial Cellular Power Level setting

 

@M0 -26dBm (Default)

@M1 -30dBm

@M2 -10dBm

@M3-@M10 -10dBm

@M11 -11dBm

...

@M31 -31dBm

 

Sets the initial power level for up shift at connect until line
conditions can be determined.

 

:En Compromise Equalizer Enable command

 

:E0 Disables the equalizer

:E1 Enables the equalizer

 

Enables or disables the V.32 compromise equalizer. This command can be
used when the modem is attached to either a flat line or a cellular
connection.

 

+MS Select Modulation

 

Note : The use of the Nn command is not recommended for speeds higher
than 14.400.

Syntax:

 

+MS=<mod>[,[<auto mode>][,[<min-rate>][,[max_rate>]]]]

 

+MS? Reports selected options

 

response : +MS:11,1,300,33600 (example)

 

+MS=? Reports supported options

response : +MS:(0,1,2,3,8,9,10,13,64,69,74),(0,1),(300-33600),(300-33600)

Sub parameter definitions:

1. Mod

 

<mod>
	

Modulation
	

Bps

0
	V.21 	300

1
	V.22 	1200

2
	V.22bis 	2400 or 1200

3
	V.23 	1200/75

9
	V.32 	9600,4800

10
	V.32bis 	14400,9600,7200, 4800,1200

11
	V.34 	33600,32100,28800, 26400,24000, 21600, 19200, 16800, 14400,9600,7200, 4800, 2400

64
	Bell 103 	300

69
	Bell 212 	1200

74
	V.FC 	28800,26400,24000,21600, 19200, 16800, 14400,9600,7200,4800,2400

 

2. <Auto mode> is an optional numeric value which enables or disables
automatic modulation negotiation using V.8 or V.32bis Annex A. The
options are :

 

0 Auto mode disabled

1 Auto mode enabled using V.8 or V.32bis Annex A

 

The default value is 1, which enables auto mode. Note, however, there
are modulations for which there is no automatic negotiation, e.g., Bell
212.

 

<Auto mode>=1

 

The modem connects at the highest possible rate in accordance with V.8
or V.32bis Annex A if V.8 is not supported by the remote modem.

 

A. If <max_rate> is greater than the highest speed supported by then
modulation specified by <mod>, the modem auto modes down from the
highest rate to the selected modulation. For example :
+MS=10,1,1200,24000 selects auto moding down from V.32bis 14400bps.

 

B. To emulate issuance of the N1 command, specify the modulation and the
rate to start auto moding down from using <mod> and <max_rate>,
respectively. Examples :

 

+MS=11,1,300,16800 auto mode at V.34 16800bps

+MS=9,1,300,12000 auto mode at V.32bis 12000bps

3. <Min_rate> is an optional number which specifies the lowest rate at
which the modem may establish a connection. The value is decimal coded,
in units of BPS, e.g. 2400 specifies the lowest rate to be 2400. The
default is 300 for 300bps.

 

3. <Max_rate> is an optional number which specifies the highest rate at
which the modem may establish a connection. The value is decimal coded,
in units of BPS, e.g. 14400 specifies the lowest rate to be 14400. The
default is 33,600 for 33,600bps.

 

 

AT Command Result Codes

The modem responds to commands from the DTE ( PC ) and to activity on
the line by signaling to the DTE in the form of result codes. The result
codes that the modem can send are described below.

Value Verbose

 

0 OK

1 RING

3 NO CARRIER

4 ERROR

5 CONNECT 1200

6 NO DIALTONE

7 BUSY

8 NO ANSWER

9 CONNECT 0600

10 CONNECT 2400

11 CONNECT 4800

12 CONNECT 9600

13 CONNECT 7200

14 CONNECT 12000

15 CONNECT 14400

16 CONNECT 19200

17 CONNECT 38400

18 CONNECT 57600

19 CONNECT 115200

22 CONNECT 75TX/1200RX

23 CONNECT 1200TX/75RX

24 DELAYED

32 BLACKLISTED

33 FAX

35 DATA

40 CARRIER 300

44 CARRIER 1200/75

45 CARRIER 75/1200

46 CARRIER 1200

47 CARRIER 2400

48 CARRIER 4800

49 CARRIER 7200

50 CARRIER 9600

51 CARRIER 12000

52 CARRIER 14400

53 CARRIER 16800

54 CARRIER 19200

55 CARRIER 21600

56 CARRIER 24000

57 CARRIER 26400

58 CARRIER 28800

59 CARRIER 31200

60 CARRIER 33600

61 CONNECT 16800

62 CONNECT 21600

63 CONNECT 24000

64 CONNECT 26400

65 CONNECT 28800

66 CONNECT 33600

67 COMPRESSION: CLASS 5

68 COMPRESSION: V.42 bis

69 COMPRESSION: NONE

70 PROTOCOL: NONE

77 PROTOCOL: LAPM

80 PROTOCOL: ALT

81 PROTOCOL: ALT-CELLULAR

+F4 +FCERROR

 

 

Supported countries

 

To change the country settings, use followingfollow next procedure :

 

AT*NCnn

Modem responds with OK

ATZ

Modem responds with OK

 

Note : Some counties do not allow their country settings to be altered.

 

*NCnn Country select

 

40 Australia

1 Austria

2 Belgium

3 Denmark

4 Finland

5 France

6 Germany

17 Greece

10 Netherlands

7 Ireland

8 Italy

43 Japan

26 Namibia

11 Norway

12 Portugal

27 South Africa

13 Spain

14 Sweden

15 Switzerland

16 UK

19 Czech Republic

24 Poland

25 Russia

22 United States

 

Note : Use the Interactive Manual™ to setup the country.

 

S-Registers

S0 Auto-answer

Sets the number of the rings required before the modem automatically
answers a call. Setting this register to zero disables auto-answer mode

Range : 0 to 255

S1 Ring counter

S1 is incremented each time the modem detects a ring signal on the
telephone line.

Range : 0 to 255

S2 Escape character

S2 holds the decimal value of the ASCII character used as the escape
sequence. A value over 127 disables the escape process.

Range : 0 to 127 (Default = 43)

S3 Carriage Return Character

Sets the command line and result code terminator character. Pertains to
asynchronous operation only.

Range : 0 to 127 ASCII decimal (Default=13)

S4 Line feed Character

Sets the character recognised as a line feed. Pertains to asynchronous
operation only.

Range : 0 to 127 ASCII decimal (Default=10)

S5 Backspace Character

Sets the character recognised as a backspace.

Range : 0 to 32 ASCII decimal (Default=8)

S6 Wait for dialtone

Sets the time in seconds that the modem will try to detect a dialtone
(if set) and wait before starting to dial.

Range : 2 to 255 seconds

S7 Wait for Carrier after dial

Sets the time in seconds that the modem will wait for a carrier before
hanging up.

Range : 1 to 255 seconds

S8 Pause time for delay

Sets the time the modem must pause when the ‘,’ dial modifier is used.

Range : 0 to 255 seconds

S9 Carrier detect response time

Sets the time in 10th of a second, that the carrier must be present
before the modem considers it valid and turns on RLSD.

Range : 1 to 255 tenths of a second.

S10 Lost carrier to Hang-up delay

Sets the time in 10th of a second, that the modem waits before hanging
up after a loss of carrier.

Range : 1 to 255

S11 DTMF Tone duration

Range : 50 to 255 milliseconds (Default=95)

S12 Escape Prompt Delay

Defines the maximum period, in fifties of a second, allowed between
receipt of the last character of the three escape character sequence and
the sending of the OK message.

Range : 0 to 255 1/50 of a second

S18 Test timer

Sets the length in seconds that the modem conducts a test.

Range : 0 to 255 seconds

S25 Delay to DTR

Sets the time that the modem will ignore DTR before taking action
specified by &Dn.

Range : 0 to 255 seconds

S26 RTS to CTS delay

Sets the time delay, before the modem turns on CTS after detecting an
OFF-ON transition on RTS when &R0 is commanded.

Range : 0 to 255 hundredths of a second

S32 XON Character

Range : 0 to 255 ASCII decimal (Default=17)

S33 XOFF Character

Range : 0 to 255 ASCII decimal (Default=19)

S38 Delay Before Forced Hang-up

This register sets the delay between the modem’s receipt of the H
command to disconnect and the disconnect operation.

Range : 0 to 255 seconds

S86 Call Failure Reason Code

When the modem issues a NO CARRIER result code, a value is written to
this S-register.

Range : 0,4,5,9,12,13 or 14

0 Normal disconnect, no error occurred

4 Loss of carrier

5 V.42 negotiation failed

9 The modems could not find a common protocol

12 Normal disconnect initiated by the remote modem

13 Remote modem does not respond after 10 re-transmissions of the same
message.

14 Protocol violation

S91 PSTN Transmit level Attenuation

Sets the transmit level attenuation level from 0 to 15dBm for the PSTN
mode. Some countries may not permit changing the transmit level.

Range : 0 to 15dBm (Corresponding to 0 to -15dBm transmit level)

Default : 10dBm

S95 Extended Result Codes The bits in this register can be set to
override some of the Wn command options. A bit set to a 1 in this
register will enable the corresponding result code regardless of the Wn
setting.

Bit 0 Connect message indicates DCE speed

Bit 1 Append /ARQ to CONNECT XXXX

Bit 2 Enable CARRIER XXXX message

Bit 3 Enable PROTOCOL message

Bit 4 Reserved

Bit 5 Enable COMPRESSION XXXX

Bit 6 Reserved

Bit 7 Reserved