AT Command Set and Register Summary for V.34 and 56K 12-Port Modules

This document describes AT commands and S and :T registers for the following universal access server modules:

• V.34 12-port module

  • V.34 modulation, 28.8 kbps, firmware version 1.x.x

  • V.34 annex 12 modulation, 33.6 kbps, firmware version 2.x.x

• 56K 12-port module

  • K56flex modulation, 56.6 kbps, firmware version 3.x.x

If you have questions or need help, refer to the last section "Cisco Connection Online" for further information.

This document contains the following sections:

• Entering AT Commands, page 2

• Alphabetic Command Set, page 4

• ^ Caret Command Set, page 10

• $ Dollar Command Set, page 11

• % Percent Command Set, page 11

• & Ampersand Command Set, page 22

• ) Parenthesis Command Set, page 25

• * Asterisk Command Set, page 26

• - Hyphen Command Set, page 26

• : Colon Command Set, page 35

• @Character Command Set, page 36

• \ Backslash Command Set, page 37

• # Character Command Set, page 50

• Modem S and

• S Register Descriptions, page 52

• PoS Support, page 71

• Cisco Connection Online, page 73

Entering AT Commands

Keep in mind the following guidelines when you send AT commands to a modem:

• Entering AT command mode involves two main configuration tasks: configuring a manageable modem to permit a direct-connect session and then establishing the session. Table 1 describes all the steps necessary to enter AT command mode on the access server.

• To exit a direct-connect session with a modem, press Ctrl-C.

• All commands except A/ (Repeat Last Command) and +++ (Escape Code) are preceded by the AT prefix and are executed when you press Return or Enter.

• Enter commands as either uppercase or lowercase, not mixed case.

• Commands are limited to 98 characters, not including the AT prefix, Return, and space characters.

• A missing numeric argument is assumed to be zero. For example, the Data Echo command \E is equivalent to \E0.

• The modem operates in one of two modes: idle state (no connection established with another modem) or connect state. Use the following commands to change operating states:

  • To enter command state from connect state without breaking the connection, enter +++ (Escape Code) without pausing and do not press Return.

  • To return to connect mode, enter AT0 and press Return.

Alphabetic Command Set

This section describes modem commands that begin with an alphabetic (A to Z) character.

A (Answer)

Forces the modem off-hook in answer mode, regardless of the value of register S. If result codes are enabled, the workstation displays RING (long form) or 2 (short form) when it receives a call.

A/ (Repeat Last Command)

Reexecutes the last command one time. A/ is not preceded by the AT prefix and is not followed by a Return.

AT (Attention)

Informs the modem that commands are being sent to it. AT must precede all other commands except A/ and +++.

Bn (ITU/Bell Mode)

Selects the ITI-U/Bell connection mode used when connecting at 300 and 1200 bps. Bn is ignored when the modem port is set to other speeds. Table 2 lists command options.

D {dial string} (Dial)

Dials a telephone number to establish a connection. The Dial command must be the last command on the command line. The dial string can contain up to 98 characters; valid characters are the digits 0 to 9, the dial modifiers listed in Table 3, and # and * for tone dialing. The modem ignores invalid characters; dial strings longer than 98 characters return an error. For example, to dial the telephone number 1 617 555 1234, enter the following command:

D 16175551234

To cancel the Dial command, press any key or set Data Terminal Ready (DTR) to off unless &D0 (DTR ignored) is set. After disconnect, there is a five-second delay before the modem is set off-hook in originate mode.

Dial Modifiers

The dial modifiers listed in Table 3 add conditions to the telephone number that you are dialing. You can use several dial modifiers with the same telephone number, and, unless otherwise noted, you can place dial modifiers anywhere in the dial string.

En (Command Echo)

Configures the modem to echo commands to the workstation. Table 4 lists command options.

Default

E1

H (Hang Up)

Disconnects from the remote system and hangs up the telephone line. If the %Dn (Disconnect Buffer Delay) time is nonzero, the hangup can be delayed until the modem has transmitted all data in its transmit buffer.

In (Identification)

Displays modem information and results of checksum tests on firmware. Table 5 lists identification command options.

On (Enter Connect State)

Sets the modem to connect state. Table 6 lists command options.

Qn (Quiet)

Configures the modem to send result and status codes, such as OK, BUSY, and RING, to your workstation. Table 7 lists command options.

Default

Q0

Sn? (Read Configuration Register)

Displays the contents of S register n (where n is a decimal number).

Range

0 to 27

Default

S0

T (Tone Dial)

Sets the current dialing mode to tone. This is the default dialing mode.

Vn (Result Code Form)

Selects the result code format sent to your workstation. The \Vn command (Error Correction Result Code Form) modifies the connect messages to reflect a reliable link connection. Table 8 lists command options.

Default

V1

Wn (Connection Speed Reporting)

Displays the serial port or modem port speed in connect messages. When the X0 command (Extended Result Codes) is set, CONNECT displays for any Wn command option. Table 9 lists command options.

Default

W2

Xn (Extended Result Codes)

Selects the extended result code format sent to the workstation. Table 10 lists command options.

The following commands also affect the result code format:

• The Vn command (Result Code Form) selects short or long form result codes.

• The \Vn command (Result Code Form) or -M1 command (MNP Class Connect Messages) must be set to indicate MNP reliable mode in the result code.

When the modem is set to ignore dial tone, it waits for the register S6 time delay and dials with or without a dial tone.

Default

X4

Yn (Long Space Disconnect)

Configures the modem to send a four-second Break on receipt of an H command (Hang Up). The answering modem disconnects if it receives the Break. This command is used only in normal and direct connections. Table 11 lists command options.

The four-second Break is also sent if Y1 and one of the following &Dn commands (Data Terminal Ready Control) are set:

• &D2 is set and DTR drops.

• &D3 is set and DTR drops. The sending modem disconnects after the Break.

Default

Y0

Z (Reset)

Hangs up the telephone line, clears the modem and the serial port buffers, and restores any settings stored with the &W or *W commands. If no settings are stored, the command restores the factory default (&F) settings.

Caret Command Set

This section describes modem commands that begin with a caret (^) character.

^H (Host Port Upgrade)

Copies new firmware from a computer file to the modem's Flash memory.

^V (Display Bootstrap Revision)

Displays the modem's current Flash memory bootstrap revision.

Dollar Command Set

This section describes modem commands that begin with a dollar ($) character.

$Bn (Serial Port Bps Rate)

Sets the serial port rate to n bps.

Range

300, 600, 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200 bps

Default

$B115200

$D (Power-Up Diagnostics)

Runs power-up diagnostics.

Percent Command Set

This section describes modem commands that begin with a percent (%) character.

%An (Autoreliable Fallback Character)

Specifies the ASCII character recognized as the autoreliable fallback character on the answering modem. In autoreliable mode, when the modem encounters an incoming autoreliable fallback character from the remote system, it automatically switches to normal mode and passes the character to the serial port. Autoreliable fallback character recognition stops if the modem receives a SYN character (decimal 22). The \N3 (Operating Mode) and \C2 (Autoreliable Buffer) commands must also be set.

Caution Do not use the settings n = 63 or n = 126. They interfere with V.42.

Range

0 to 127 (ASCII decimal)

Default

%A0 (autoreliable fallback character is disabled)

%Bn (Modem Port Bps Rate)

Sets the modem port data rate. Downshifting can still occur.

The %Bn command is affected by the following %Gn command (Independent Serial/Modem Port Speed) options:

• If %G0 is sent locally, the modem port speed is matched to the serial port speed, regardless of any previous %Bn setting.

• If %G1 is set, the modem speed changes only when a %Bn command is entered.

Range

300, 600, 1200, 2400, 4800, 7200, 9600, 12000, 14400, 16800, 19200, 21600, 24000, 26400, 28800, 31200, 32000, 34000, 33600, 36000, 38000, 40000, 42000, 44000, 46000, 48000, 50000, 52000, 54000, 56000 bps

Default

%B33600 for V.34 modems
%B56000  for 56 kbps modems

%Cn (Compression Control)

Sets the modem to use a data compression method in reliable connections. The recommended default command setting of %C3 allows the modem to establish a reliable connection using V.42 bis compression or MNP Class 5 Data Compression, depending on the capability of the remote modem.

If the remote modem does not support data compression or has data compression disabled, the modem can establish a noncompression connection with any %Cn setting.

Throughput is affected by the \Jn command (Bps Rate Adjust) options:

• \J0 (Disable Bps Rate Adjust) is recommended for the highest throughput.

• \J1 (Enable Bps Rate Adjust) causes the serial port to adjust to 9600 bps when a reliable connection is established at a speed from 2400 to 14400 bps. At 16800 bps or higher, the serial port speed adjusts to 19200 bps.

Default

%C3

%Dn (Disconnect Buffer Delay)

Specifies a delay time for the modem to process data in its transmit or receive buffers before disconnecting. When DTR transitions off or an H command (Hang Up) is entered, the modem attempts for n seconds to empty its transmit buffer before disconnecting. When carrier transitions off, the modem attempts for n seconds to empty its receive buffer before disconnecting. If the buffers are empty or if n = 0, the modem disconnects immediately.

If a physical disconnect occurs (for example, the connection is lost), only the receive buffer can be processed. If the delay expires before the modem empties its buffers, or if the modem is in command state at disconnect, data can be lost. The receive buffer may not empty before disconnecting if %E1 (Autoretrain) is set during normal mode connections at 2400 bps or higher.

Range

0 to 255 seconds

Default

%D0

%En (Autoretrain)

Sets the modem to resynchronize (autoretrain) up to three times (for a total of up to 6 seconds) before hanging up. The modem resynchronizes only for connection speeds of 2400 bps or higher. The %En command is ignored in V.32 communication. Table 13 lists command options.

Default

%E1

%Fn (V.23 Mode)

Configures the modem for V.23 mode. Table 14 lists the V.23 command options.

Default

%F0

%Gn (Independent Serial Port and Modem Port Speed)

Sets the modem port speed independent of the serial port speed. The modem port speed is set by the %Bn command (Modem Port Bps Rate). Table 15 lists command options.

Default

%G0

• Table 16 lists commands for modem protocols up to 14400 bps.

• Table 17 lists commands for V.34 modem port speeds up to 33600 bps.

• Table 18 lists commands for 56 kbps modem port speeds up to 56000 bps.

%Ln (Speed Matching)

Configures the modem to use speed matching when establishing a connection. Table 19 lists command options.

Default

%L1

Modem Connection Modes Using Speed Matching

The following tables list connections the modem can establish with %L1 or %L3 set.

• Table 20--lists connections if a 56K modem in the access server originates the call.

• Table 21--lists connections if a 56K modem in the access server answers the call.

• Table 22--lists connections if a V.34 modem in the access server originates the call.

• Table 23--lists connections if a V.34 modem in the access server answers the call.

Restricted Speed Matching

Use the %L0 or %L2 command options on both originating and answering modems to restrict the connection speed. Table 24 lists connection speeds using the %L0 partial speed matching option. Table 25 lists connections speeds using the %L2 speed matching disabled option. If %L2 is set, the modem speed matches the closest possible connection speed.

%Mn (Modulation Selection)

Sets the modem modulation mode. Table 26 lists command options.

Default

%M2 for V.34 modules
%M3 for 56 kbps modules

%Rn (Read All Registers)

Displays the contents of modem S and :T registers as a table of values in decimal and hexadecimal format. Table 27 lists command options.

at%r0
REG  DEC  HEX    REG  DEC  HEX
S00  001  01H    S14  138  8AH
S01  000  00H    S15  000  00H
S02  043  2BH    S16  000  00H
S03  013  0DH    S17  000  00H
S04  010  0AH    S18  000  00H
S05  008  08H    S19  000  00H
S06  002  02H    S20  000  00H
S07  060  3CH    S21  048  30H
S08  002  02H    S22  118  76H
S09  006  06H    S23  030  1EH
S10  060  3CH    S24  000  00H
S11  075  4BH    S25  005  05H
S12  050  32H    S26  001  01H
S13  000  00H    S27  064  40H
S13  000  00H    S27  064  40H
OK

%Un (Clear Serial Port Speed)

Sets the serial port speed. Table 28 lists command options.

Default

%U1

%V (Display Modem Firmware Version)

Displays the modem firmware version and country code. (For country code listings, see Table 40 on page 28.)

Default

%V1

Ampersand Command Set

This section describes modem commands that begin with an ampersand (&) character.

&Cn (Serial Port DCD Control)

Controls the Data Carrier Detect (DCD) signal level. Use this command if your workstation requires DCD to be off at certain times. Table 30 lists command options. See also the \Dn command.

Default

&C1

&Dn (DTR Control)

Specifies the modem action when Data Terminal Ready (DTR) transitions off. The on-to-off transition of DTR must last as long as the value specified in register S25. Positive transitions of DTR (off-to-on) within five seconds after disconnect are ignored. Table 31 lists command options.

Default

&D3

&F (Restore Command Defaults)

Restores the factory default configuration. Stored telephone numbers are not cleared.

&Gn (Guard Tone)

Sets the guard tone frequency on the answering mode. Table 32 lists command options.

Default

&G0

&Pn (Dial Pulse Ratio)

Sets the ratio of off-hook (make) to on-hook (break) time that the modem uses for pulse dialing. Table 33 lists command options.

Default

&P0

&Sn (DSR Options)

Sets the serial port Data Set Ready (DSR) signal. Table 34 lists command options.

Default

&S0

&Tn (Diagnostic Test Mode)

Configures the modem to run a local or remote diagnostic test. Use the &T0 command to stop a running diagnostic test.Table 35 lists command options.

Default

&T5

&W (Store Current Configuration)

Stores the current configuration. The &W command stores the active commands and S registers, except restricted S registers S2 to S12, and the serial port speed and parity and modem port speed in effect when you enter the command. Telephone numbers are stored independently with the \Pn and &Zn commands.

Parenthesis Command Set

This section describes modem commands that begin with a right-parenthesis ()) character.

)Mn (Power Level Adjustment for Cellular Telephone Connections)

Adjusts power levels during link negotiation for reliable connections to accommodate signaling requirements of cellular telephone equipment. Table 36 lists command options.

Default

)M0

Asterisk Command Set

This section describes modem commands that begin with an asterisk (*) character.

*I (Modem Identifier)

When the *I command is entered, the following prompt appears:

ID:

The identifier can consist of up to 25 ASCII characters. It is truncated after the 25th character. The modem identifier is also displayed by the \S command (Read Online Status).

Default

No default identifier.

*W (Store Complete Configuration)

Stores the complete modem configuration. The *W command stores the active commands and S registers, including the current values of restricted S registers S2 to S12 (which are not stored with &W), and the serial port speed and parity and modem port speed in effect when you enter the command. Telephone numbers are stored independently with the \Pn and &Zn commands.

Hyphen Command Set

This section describes modem commands that begin with a hyphen (-) character.

-D{dial string} (Repeat Dial)

Redials a telephone number, up to nine times, until a connection is made. In reliable mode, the modem does not redial the number if the remote modem answers but fails to establish a reliable connection. Table 37 lists command options.

The dial string contains up to 98 characters. Valid dial string characters are 0-9, the dial modifiers listed in Table 3, and the # and * characters for tone dial. The modem ignores invalid characters.

-En (Modem Port Data Length)

Specifies the number of data bits used on the modem port during normal mode connections when the \N0 command (Operating Mode) is set, and the serial port is configured for asynchronous transmission of 11-bit characters. Both modems must be set to the same number of data bits. Table 38 lists command options.

The modems cannot pass data when a \N3 or \N5 reliable connection is set and falls back to a normal connection with 11-bit data characters enabled on both modems.

Default

-E0

-Hn (Dumb Mode)

Configures the modem to smart mode (recognize commands on the Data Terminal Equipment [DTE] port and send result codes) or dumb mode (ignore commands on the DTE port and do not send result codes). Table 39 lists command options.

Default

-H0

-In (Country Code)

Sets the country code for the modem. The code does not take effect until the modem has been reset by the Z (Reset) command or a power cycle. Table 40 lists country codes.

Country codes that are set manually (that is, not following the procedure described in the next section, will remain in effect until one of the following events occur:

• Another -I command is sent.

• The firmware is reloaded. (Firmware reloads will always reset the country code to USA.)

• The access server is power cycled.

• The access server is reloaded.

Changing Country Codes on Microcom Modems

This section describes how to change the country code on Microcom modems in Cisco universal access servers. The default country code is USA. The USA country code is also used for the following countries: Argentina, Brazil, Canada, Chile, China, Columbia, Hong Kong, India, Indonesia, Korea, Malaysia, Mexico, Peru, Philippines, Singapore, Taiwan, and Thailand. If you are using the modems in a different country, you must change the country code.

Configure

Take these steps:

Step 1 Enter global configuration mode:

Router> enable
Router# config term
Enter configuration commands, one per line. End with CNTL/Z.
Router(config)#

Step 2 Edit the new modemcap and specify the country code (-InZ) in the miscellaneous attributes field. Substitute n with one of the country codes listed in the Country Code column of Table 40. In the following example, the country code is set to "18" for the Czech/Slovak Republic:

Router(config)# modemcap edit micro_czech miscellaneous -I18Z

Step 3 If you are using the country code for Belgium, the Czech/Slovak Republic, France, or Switzerland, additional configuration is required. These country codes are set by default to answer on the second ring (that is, the s-register is set to s0=2). This default setting conflicts with the Cisco IOS software default fast-answer feature, which answers after only one ring.

Verify

Verify the configuration changes using one of the following methods.

The following example shows verification from the router command prompt:

Router# show modemcap mcom_czech
Modemcap values for mcom_czech
Factory Defaults (FD):  [not set]
Autoanswer (AA):  [not set]
Carrier detect (CD):  [not set]
Drop with DTR (DTR):  [not set]
Hardware Flowcontrol (HFL):  [not set]
Lock DTE speed (SPD):  [not set]
DTE locking speed (DTE):  [not set]
Best Error Control (BER):  [not set]
Best Compression (BCP):  [not set]
No Error Control (NER):  [not set]
No Compression (NCP):  [not set]
No Echo (NEC):  [not set]
No Result Codes (NRS):  [not set]
Software Flowcontrol (SFL):  [not set]
Caller ID (CID):  [not set]
On-hook (ONH):  [not set]
Off-hook (OFH):  [not set]
Miscellaneous (MSC):  -i18z		
Template entry (TPL):  [not set]
Router#

The following example shows verification using debug:

Step 1 Enable modem debug:

Router# debug confmodem
Modem Configuration Database debugging is on
Router# debug modem
Modem control/process activation debugging is on
Router#

Step 2 Clear an idle line:

Router# clear line 1
[Confirm]
OK

DTR drops and modem autoconfigure runs when the modem is reset. It may take a minute while the messages display:

Router#
*Mar 3 23:20:26.114: TTY1: Line reset
*Mar 3 23:20:26.118: TTY1: Modem: IDLE->HANGUP
*Mar 3 23:20:26.534: TTY1: dropping DTR, hanging up
*Mar 3 23:20:26.534: tty1: Modem: HANGUP->IDLE
*Mar 3 23:20:31.838: TTY1: restoring DTR
*Mar 3 23:20:32.958: TTY1: Modem command: --AT&F&C1&D2:T26=8-I18Z
\ Q3\N5-K0\J0%C3$B115200S0=2H0--
*Mar 3 23:20:34.234: TTY1: Modem configuration succeeded
*Mar 3 23:20:36.090: TTY1: locking speed (115200) response ---OK---
*Mar 3 23:20:36.090: TTY1: locked DTE speed at 115200
*Mar 3 23:20:36.094: TTY1: Done with modem configuration

Step 3 Verify that the country code has changed:

Router#modem at-mode 0/0
You are now entering AT command mode on modem (slot 0 / port 0).
Please type CTRL-C to exit AT command mode.
at%v1

MNP Class 10 V.34/V.FC Modem Rev 3.1.30/91

OK

The example shows Rev 2.1.9/91. Locate "91" in the "Country Code Displayed in Banner" column of Table 2. Notice that "91" is for the Czech/Slovak Republic.

Step 4 Press Ctrl-C to exit the direct-connect session.

This concludes the procedure for changing the country code.

-Jn (Detect Phase)

Configures the originating modem to send a control sequence to the answering modem to determine the type of error correction enabled, either LAPM, MNP, or none. See the \Nn command (Operating Mode) for information about the types of connections that can be established. Table 41 lists command options.

Default

-J1

-Kn (MNP Extended Services)

Configures the modem to use MNP extended services that are not available when operating in LAPM mode. For example, two modems with MNP extended services enabled negotiate MNP Class 10 with V.42 bis compression instead of LAPM. Table 42 lists command options.

Default

-K1

-Mn (MNP Class Connect Messages)

Determines whether MNP class connect messages are displayed. lists command options.

The -M1 setting overrides the \V command (Error Correction Result Code Form) for long-form connection result codes and the Wn command (Connection Speed Reporting) for serial-port connect messages. The following commands override the -Mn command:

• V0 (short form result codes enabled)

• X0 (extended result codes disabled) displays only CONNECT

Default

-M0

-On (Serial Port Parity)

Changes the serial port parity set by the AT sequence. Use this command when the local device supports XON/XOFF flow control and detects parity to ensure that all modem-generated XON and XOFF characters have the correct parity. Table 44 lists command options.

You can also use the -On command to change the serial port parity while connected to a remote device. Modem port parity cannot be changed after a connection is established. When the parity required for a connection is not the parity set by the sequence, you must set the correct parity when you enter the Dial command, as part of the same command line.

The AT sequence cannot be used to match space parity; no parity is set instead. You must enter -O3 to set space parity.

Default

-O4

-Pn (Check Parity)

Controls parity checking of XON and XOFF characters, the escape code sequence, and HP ACK characters. In command state, all command echoes and command responses from the modem are sent to the workstation with parity that matches the serial port parity. Table 45 lists command options.

Default

-P0

-Qn (Fallback Modulation Speed)

Configures the modem to fall back from a V.32 bis or V.32 MNP reliable connection at 14400, 9600, 7200, or 4800 bps to a V.22 bis MNP reliable connection at 2400 bps or a V.22 MNP reliable connection at 1200 bps. Fallback can occur when poor telephone lines cause excessive MNP retransmissions. Table 46 lists command options.

Fallback from a V.32 bis or V.32 MNP reliable connection to V.32 bis or V.32 at 4800 bps is always enabled for any -Qn command option. The modem always uses the V.22 standard when it falls back from a V.32 MNP reliable connection to a 1200 bps MNP reliable connection for any Bn setting (ITI-U/Bell mode).

Default

-Q2

-V (Split Modem Port Speed with Multiprotocol Autoanswer)

Determines whether the modem port uses split transmit and receive speed operation when using the multiprotocol autoanswer feature. %F0 must also be set. Note that V.23 is the split speed on the modem link (that is, 75/1200 bps).

Default

-V1 for U.S.
-V0 for international

Colon Command Set

This section describes modem commands that begin with a colon (:) character.

:Dn (Manual Dial)

Sets the modem off-hook in originate mode when DTR is raised. Table 48 lists command options.

Default

:D0

:En (Compromise Equalizer)

Configures the modem to use the compromise equalizer when it connects in V.32 mode. Table 49 lists command options.

Default

:E1

:Tn? (Read Configuration Register)

Displays the contents of :T register n (where n is a decimal number).

@Character Command Set

This section describes modem commands that begin with an at (@) character.

@Cn (CTR, DSR, and DCD Connect Message Control)

Sets DSR, Clear To Send (CTS), and DCD on before or after a connect message. Used with the :T14 (Connect Message Delay Timer) register. Table 50 lists command options.

Default

@C0

@E (Detailed Modem Call Status)

This is an unofficially supported modem status and debugging command that can be used by an experienced user to verify the detailed status of the modem during or after a call. The content of this command may change as required to assist in problem resolution. Therefore, the command may produce results that differ from the description in this document. For more information, see the section "Debugging," on page 65.

@Mn (Select Transmit Level for Cellular Connections)

Selects the initial transmit level for the connection. You can set levels from -10 to -35 decibels referred to 1 milliwatt (dBm). From @M10 to @M35, the level is the as -n dBm. Table 51 lists selected transmit level command options.

Default

@M0

@Un (Minimum Connection Speed)

Selects the minimum speed for the connection. You can set the speed n for 300, 600, 1200, 2400, 4800, 7200, 9600, 12000, 14400, 16800, 19200, 21600, 24000, 26400, or 28800 bps.

Backslash Command Set

This section describes modem commands that begin with a backslash (\) character.

\An (Maximum MNP Block Size)

Sets the maximum block size for MNP stream link connections. Table 52 lists command options.

Default

\A3

\Bn (Transmit Break)

Sends Break to the remote system for 100n milliseconds. In a reliable link, Break is always sent for 300 milliseconds. Use the O command (Enter Connect State) to return to connect state. See also the \K command (Break Control).

Range

1 to 9 (100-millisecond increments)

Default

\B3 (300 milliseconds)

\Cn (Autoreliable Buffer)

Configures the modem to buffer data in autoreliable, autoanswer mode. The answering modem's data buffer can be used to store data during the 3-second link negotiation for a reliable connection. Table 53 lists command options.

For example, you can use %A to set the autoreliable fallback character to ASCII 13 (carriage return). Then set \C2 and \N3 (autoreliable mode). Non-MNP callers who connect and press Return to log on do not need to wait for the 3-second autoreliable window to expire before data can pass. See the \Nn command (Operating Mode) for more information about autoreliable and normal modes.

The \Jn command (Bps Rate Adjust) affects the type of connection established. Reliable and direct connections can result when bps rate adjust is enabled (\J1). Reliable and normal connections may result when bps rate adjust is disabled (\J0).

Default

\C0

\Dn (Serial Port DSR/CTS Control)

Controls the DSR and CTS signals on the serial port. Use this command when the central site computer requires DSR and CTS to be off at certain times. Table 54 lists command options.

Selecting hardware flow control for the serial port overrides the \Dn command. When hardware flow control is selected, the CTS line indicates the ability of the modem to receive data from your workstation, and the DSR action does not change.

Default

\D0

Serial Port Signal Options

Use the &Cn and \Dn commands to control the serial port DCD, DSR, and CTS signal levels when your workstation requires DCD, DSR, and CTS to be off at certain times. Table 55 lists command options and signal level results.

\En (Data Echo)

Configures the modem to echo characters sent from the local workstation in connect state. Table 56 lists command options.

Default

\E0

\F (Display Stored Phone Numbers)

Displays the telephone numbers currently stored in the telephone directory.

\Gn (Modem Port Flow Control)

Sets the flow control method used to pace data between modems during a normal mode connection. Table 57 lists command options.

A reliable link has its own method of flow control and ignores the \Gn setting. The \ Qn command (Serial Port Flow Control) settings determine DTE port flow control during a reliable link.

Default

\G0

\Jn (Bps Rate Adjust)

Automatically adjusts the speed of the serial port to match the speed of the connection. Table 58 lists command options.

When a reliable connection is established at a speed between 4800 and 14400 bps and the bps rate adjust option is enabled, the serial port speed always adjusts to 9600 bps. If the connection is established at 14400 bps or higher, the serial port speed is adjusted to 19200 bps. If you set the serial port to the modem's highest rate of 115200 bps, turn off bps rate adjust so the serial port stays at 115200 bps.

Default

\J0

\Kn (Break Control)

Determines the type of Break the modem transmits when it receives a Break. Table 59 describes the effect of n. The modem can buffer up to four Breaks on both the modem port and the serial port.

Default

\K5

\Nn (Operating Mode)

Selects the modem operating mode. Table 60 lists command options.

Default

\N3

Table 61 lists connections that can be established, depending on the operating mode enabled on each modem. When more than one operating mode is listed within a column, the first mode is for the originating modem and the second is for the answering modem. NC indicates no connection.

\Pn{dial string} (Store a Telephone Number)

Stores entry n in the modem's telephone directory, where n is an integer (1 to 9) and dial string is a string of up to 98 characters. Valid dial string characters are 0 to 9, dial modifiers, and # and * for tone dialing. The modem ignores invalid characters. Dial strings longer than 98 characters return error messages. Phone numbers are not saved during a power reset.

\ Qn (Serial Port Flow Control)

Selects the flow control method used in the serial port. In direct mode connections, the modem ignores the \ Qn command. Table 62 lists command options.

Default

\ Q3

\Rn (Serial Port Ring Indicator)

Controls the Ring Indicator (RI) signal. RI follows the incoming ring signal on the telephone line. Table 63 lists command options.

Default

\R1

\Sn (Read Online Status)

Displays a list of modem commands and their current settings, the active connection type, the elapsed connect time, and the telephone number most recently dialed. The \S0 command outputs a single-screen display ( press any key for the next screen). The \S1 command outputs a continuous screen display. Press Ctrl-X or Break to cancel the display.

The following display is an example of \S1 command output with factory default settings for a V.34 modem:

at\s1
IDLE           000:02:01
LAST DIAL      t1714756,0947
NET ADDR:      FFFFFFFFFFFF
MODEM HW: OEM 2W United States
4 RTS 5 CTS 6 DSR - CD 20 DTR - RI 
MODULATION     IDLE
MODEM BPS      33600  AT%G0   
MODEM FLOW     OFF    AT\G0
MODEM MODE     AUT    AT\N3
V.23 OPR.      OFF    AT%F0
AUTO ANS.      ON     ATS0=1
SERIAL BPS     115200 AT%U1   
BPS ADJUST     OFF    AT\J0
SPT BPS ADJ.   0      AT\W0
ANSWER MESSGS  OFF    ATQ2   
SERIAL FLOW    BHW    AT\Q3
PASS XON/XOFF  OFF    AT\X0
PARITY         8N     AT
BREAK          5      AT\K5
EXIT CHAR      043    ATS2=43
ANS DUMB MODE  ON     AT#E1
CMD ECHO       ON     ATE1
RESULTS        OFF    ATQ2
RESULT TYPE    MNPX   ATV1\V2
CONNECT MSG    MDM    ATW2
CONN MNP-      0      AT-M0
SPEED MATCH    1      AT%L1
EQUALIZER      1      AT:E1
FALLBACK       2      AT-Q2
DATA ECHO      OFF    AT\E0
INACT TIMER    00     AT\T0
AUTO RETRAIN   ON     AT%E1
COMPRESSION    ALL    AT%C3
MAX BLK SIZE   256    AT\A3
AUTO BUFF      0      AT\C0
AUTO CHAR      000    AT%A0
EMULATING HP   OFF    AT\H0
PAUSE TIME     002    ATS8=2
DTR            3      AT&D3
MABP ADDRESS   001    AT^P1
CARR DET       1      AT&C1
DSR            0      AT\D0
RING IND       1      AT\R1
SPKR CTRL      1      ATM1
SPKR VOL       2      ATL2
LNG SPC DISC   OFF    ATY0
DISC DELAY     000    AT%D0
RDLB ENABLE    OFF    AT&T5
DIAL MODE      4      ATX4   
PULSE DIAL     60%    AT&P0
PULSE MODE     N      AT%W0
V23 HD EQU     ON     AT%O1
GUARD TONE     0      AT&G0
DATA CALL TONE OFF    AT-C0
2ND FC         OFF    AT-F0
NM BIT VALUE   0      AT-E0
PAR CHK        0      AT-P0
MANUAL DIAL    0      AT:D0
UPSHIFT BPS    OFF    AT*H0
CELLULAR       OFF    AT)M0
LINETYPE       000    AT@M0
DETECT PHASE   ON     AT-J1
MNP EXT SVC    1      AT-K1
UNIV V.23      1      AT-V1
CONNECT MSG    1ST    AT@C0
DUMB MODE      OFF    AT-H0
BELL           ON     ATB1
CALL ABT DISAB OFF    AT-Y0
REVERSE ANS    OFF    AT-W0
MIN CONN SPD   300    AT@U
OK

The following display is an example of \S1 command output with factory default settings for a 56K modem:

at\s1
IDLE           000:00:00
LAST DIAL
NET ADDR:      FFFFFFFFFFFF
MODEM HW: OEM 2W United States
4 RTS 5 CTS 6 DSR - CD 20 DTR - RI
MODULATION     IDLE
MODEM T/R BPS  *****  *****
MODEM BPS      56000  AT%G0
MODEM FLOW     OFF    AT\G0
MODEM MODE     AUT    AT\N3
BASE MODE      K56    AT%M3
V.23 OPR.      OFF    AT%F0
AUTO ANS.      ON     ATS0=1
SERIAL BPS     115200 AT%U1
BPS ADJUST     OFF    AT\J0
SPT BPS ADJ.   0      AT\W0
ANSWER MESSGS  ON     ATQ0
SERIAL FLOW    BHW    AT\Q3
PASS XON/XOFF  OFF    AT\X0
PARITY         8N     AT
BREAK          5      AT\K5
EXIT CHAR      043    ATS2=43
ANS DUMB MODE  ON     AT#E1
CMD ECHO       ON     ATE1
RESULTS        ON     ATQ0
RESULT TYPE    MNPX   ATV1\V2
CONNECT MSG    MDM    ATW2
CONN MNP-      0      AT-M0
SPEED MATCH    1      AT%L1
EQUALIZER      1      AT:E1
FALLBACK       2      AT-Q2
DATA ECHO      OFF    AT\E0
INACT TIMER    00     AT\T0
AUTO RETRAIN   ON     AT%E1
COMPRESSION    ALL    AT%C3
MAX BLK SIZE   256    AT\A3
AUTO BUFF      0      AT\C0
AUTO CHAR      000    AT%A0
EMULATING HP   OFF    AT\H0
PAUSE TIME     002    ATS8=2
DTR            2      AT&D2
MABP ADDRESS   003    AT^P3
CARR DET       1      AT&C1
DSR            0      AT\D0
RING IND       1      AT\R1
SPKR CTRL      1      ATM1
SPKR VOL       2      ATL2
LNG SPC DISC   OFF    ATY0
DISC DELAY     000    AT%D0
RDLB ENABLE    OFF    AT&T5
DIAL MODE      4      ATX4
PULSE DIAL     60%    AT&P0
PULSE MODE     N      AT%W0
V23 HD EQU     ON     AT%O1
GUARD TONE     0      AT&G0
DATA CALL TONE OFF    AT-C0
2ND FC         OFF    AT-F0
NM BIT VALUE   0      AT-E0
PAR CHK        0      AT-P0
MANUAL DIAL    0      AT:D0
UPSHIFT BPS    OFF    AT*H0
CELLULAR       OFF    AT)M0
LINETYPE       000    AT@M0
DETECT PHASE   ON     AT-J1
MNP EXT SVC    1      AT-K1
UNIV V.23      1      AT-V1
CONNECT MSG    1ST    AT@C0
DUMB MODE      OFF    AT-H0
BELL           ON     ATB1
CALL ABT DISAB OFF    AT-Y0
REVERSE ANS    OFF    AT-W0
MIN CONN SPD   300    AT@U
OK

\Tn (Inactivity Timer)

Specifies the time, in minutes, that the modem waits before hanging up when data is not sent or received. The inactivity timer is available only during normal and reliable link connections. \T0 disables the timer.

Range

0 to 90 minutes

Default

\T0 (disabled)

\Vn (Error Correction Result Code Form)

Sets the result code format to display a reliable link connection. The speed field content is determined by the Wn command (Connection Speed Reporting) setting. Setting -M1 (MNP Class Connect Messages) changes the format of the long form connection result codes. Table 64 lists command options.

Set V0\V3 if your software requires Hayes-compatible connection result codes. When V1 is set to select long form result codes, \V3 is equivalent to \V2.

Default

\V2

\Wn (Split Serial Port Speed)

Determines whether the serial port uses split transmit and receive speed operation when %F1 or %F2 is set to select V.23 mode. Table 65 lists command options.

Default

\W0

\Xn (XON/XOFF Passthrough)

Determines whether XON/XOFF flow control characters are sent to the remote or local modem. When XON/XOFF flow control is enabled on the serial port (\ Q1) and XON/XOFF passthrough is enabled (\X1), the modem transmits any XON and XOFF characters sent to the serial port from the local device to the remote device. Table 66 lists command options.

Default

\X0

Caution With \X0 (XON/XOFF passthrough) set and XON/XOFF flow control enabled, local devices such as printers can send XON and XOFF characters to the modem serial port. If the modem is controlling the flow of data to the remote system, these local flow control characters will not interfere with the connection. However, if \X1 is set, the local flow control characters also pass through to the remote system. These characters can turn on the flow of data from the remote system before the modem is ready to receive it, resulting in loss of data.

# Character Command Set

This section describes modem command that begins with a # character.

#En (Answer Mode Escape Sequence)

Determines detection of the escape sequence (+++) when the modem is in answer mode.

Default

#E1

Modem S and :T Register Summary

The modem saves configuration settings in S and :T registers similar to Hayes Smartmodem 2400 registers. Each register controls a single modem function or is bit-mapped to control several functions. This section describes commands to display and change register values. We recommend that, wherever possible, you use the following commands only to display register contents and use the AT command set to change register values.

Read All Registers

The %Rn command displays the contents of an entire register set. The register set contents are displayed as a table in decimal and hexadecimal format.

%R0 displays the contents of all S registers.

%R1 displays the contents of all :T registers.

Point to a New Reference Register

The Sn and :Tn commands set the modem register pointer to register n. Register n then becomes the reference register for following register commands.

ATSn sets the modem register pointer to S register n.

AT:Tn sets the modem register pointer to :T register n.

Read a Configuration Register

The Sn? and :Tn? commands display the contents of register n, in decimal format only. Register n becomes the reference register.

ATSn? displays the contents of S register n.

AT:Tn? displays the contents of :T register n.

Change the Value of a Register

The Sn=x and :Tn=x commands change the value of register n to x. Register n becomes the reference register.

ATSn=x changes the value of S register n to x.

AT:Tn=x changes the value of :T register n to x.

Display the Value of the Reference Register

The AT? command displays the value of the last S register referenced in a read, write, or pointer command.

Change the Value of the Reference Register

The AT=x command changes the value of the last S register referenced to x.

S Register Descriptions

This section describes the purpose and format of each S register.

S0 (Ring to autoanswer On)

Register S0 specifies the number of rings before the modem answers. Set register S0 to zero to disable autoanswer. Ring signals are ignored for 5 seconds after disconnect.

Range

0 to 255 rings

Default

1 ring

S1 (Ring Counter)

Counts the rings before the modem answers a call. If there is no ring within eight seconds of the last ring, S1 is reset to zero. Ring signals are ignored for five seconds after disconnect.

S2 (Escape Code Character)

Specifies the character used for the three-character escape code sequence. When the modem is in connect state and receives the escape code sequence, it enters command state. Setting register S2 to zero disables the escape code character. Register S12 sets the guard time that must be present before and after the escape code character.

Range

0 to 255 (ASCII decimal)

Default

43 (+)

S3 (Carriage Return Character)

Specifies the carriage return (CR) character. The carriage return terminates command lines and result codes.

Range

0 to 127 (ASCII decimal)

Default

13 (Carriage Return)

S4 (Line Feed Character)

Specifies the linefeed (LF) character. The linefeed character follows a carriage return at the end of command lines and result codes.

Range

0 to 127 (ASCII decimal)

Default

10 (Linefeed)

S5 (Backspace Character)

Specifies the backspace (BS) character.

Range

0 to 32 (ASCII decimal)

Default

8 (Backspace)

S6 (Wait Before Dialing)

Specifies the time the modem waits after transitioning off-hook before dialing. This is a minimum of two seconds, even if register S6 is set to a value less than 2. Register S6 is used only when the X0, X1, or X3 command (Extended Result Code) is set.

Range

2 to 255 seconds

Default

2 seconds

S7 (Wait for Carrier After Dial)

Specifies the time that the modem waits for one of the following:

• Carrier from the remote modem before hanging up in originate or answer mode

• Ringback, only in originate mode, and only if X3 or X4 (Extended Result Codes) is set

• Dial tone when the Wait for Dial Tone (W) dial modifier is encountered in a dial string

• Quiet answer when the Wait for Quiet Answer (@) dial modifier is included in a dial string

Range

0 to 255 seconds

Default

60 seconds

S8 (Pause Time for Dial Delay)

Specifies the time the modem waits when the pause dial modifier (,) is used in a dial string.

Range

0 to 255 seconds

Default

0

S9 (Carrier Detect Response Time)

Specifies the time that a signal must be present before the modem recognizes it as carrier. Register S9 is only used in normal and direct modes.

Range

0 to 255 (0.1-second increments)

Default

6 (0.6 seconds)

S10 (Delay for Hangup After Carrier Loss)

Specifies the time the modem waits before hanging up after loss of carrier, allowing for a temporary loss. Both modems should have equal values set. If the S10 values of the two modems are unequal, disconnection occurs when the lower value is reached. When register S10 is set to 255, the modem functions as if carrier is always present. After disconnecting, the modem waits a minimum of five seconds before going off-hook in originate mode.

Range

0 to 255 (0.1-second increments)

Default

60 (6 seconds)

S11 (DTMF Tone-Dialing Speed)

Specifies the time interval in milliseconds between tones when the modem is dialing over a tone line.

Range

50 to 100 milliseconds

Default

50 milliseconds

S12 (Escape Code Guard Time and Remote Access Attention Sequence Guard Time)

Sets the minimum quiet time before and after the three-character escape code. The interval between characters in the escape code or remote access attention sequence must be less than this guard time. If S12 is zero, the time to enter the escape code or attention sequence does not affect recognition.

In normal mode, register S12 sets the guard time that precedes and follows the attention character sequence. It should be set to the same value on both the originating and answering modems. Reliable mode uses its own timing and ignores register S12.

Range

0 to 255 (0.02-second increments)

Default

50 (1 second)

S14 (Bit-Mapped Register)

Register S14 is bit-mapped for the functions listed in Table 68.

S16 (Bit-Mapped Register for Test Options)

Register S16 is a read-only register that displays loopback test option status and is available only when the modem is in normal or direct mode. The modem does not support diagnostic tests in Bell 103, V.13, V.21, or V.23 modes. The register is bit-mapped for the functions listed in Table 69.

S18 (Test Timer)

Specifies the maximum elapsed time for a modem loopback diagnostic test. Register S18 is available only when the modem is in normal or direct mode. If the register is set to zero, enter the &T0 command (End Test in Progress) to end a test. Register S18 is not supported for V.54 loopback tests by switch or circuit.

Range

0 to 255 seconds

Default

0 (disables the timer)

S21 (Bit-Mapped Register)

Register S21 is bit-mapped for the functions listed in Table 69.

S22 (Bit-Mapped Register)

Register S22 is bit-mapped for the functions listed in Table 71.

S23 (Bit-Mapped Register)

Register S23 is bit-mapped for the functions listed in Table 72.

S25 (Delay to DTR and Asynchronous/Synchronous Time Delay)

The modem ignores an on-to-off transition of DTR that is less than the register S25 time delay.

Range

0 to 255 (0.01-second increments for Delay to DTR, 1 second for asynchronous mode)

Default

5 (0.05 seconds for Delay to DTR, 5 seconds for asynchronous mode)

S27 (Bit-Mapped Register)

Register S27 is bit-mapped for the functions listed in Table 72.

:T Register Descriptions

This section describes the purpose and format of each supported :T register.

:T0 (Timer for V.22 bis, V.22, and V.32 Modes During Multi-Protocol Answer)

Register :T0 sets the time limit for the modem to establish a V.32, V.22 bis, or V.22 connection before switching to establish a V.23 split speed or V.21 connection. In this time period, the modem sends V.22 bis or V.22 carrier. This register setting requires 1200-bps or higher operation with %F0%L1.

Range

0 to 255 (0.1-second increments)

Default

40 (4 seconds)

:T3 (Timer for V.21 and V.23 Answer Tone Duration)

Register :T3 is used in V.21 mode (%F0 is set and the modem speed is 300 bps) or V.23 mode (%F1, %F2, or %F3).

In answer mode, register :T3 sets the time limit for the V.25 answer tone sent by the answering modem to the originating modem. When :T3 is zero, no answer tone is sent. All V.21 and V.23 answers begin with two seconds of silence before sending an answer tone, unless :T3 is zero.

In originate mode, register :T3 sets the time the originating modem waits after detecting an answer tone before proceeding with the connection. When :T3 is zero, the originating modem does not wait for an answer tone.

Range

0 to 33 (0.1-second increments)

Default

33 (3.3 seconds)

:T4 (Timer for Line Turnaround Delay and Carrier On)

Register :T4 specifies the minimum time that the modem waits for the remote modem to respond after turning carrier off before turning carrier back on again to resume sending data. Register :T4 is used only in normal mode V.23 half-duplex connections.

Range

0 to 255 (12.5-millisecond increments)

Default

20 (250 milliseconds)

:T6 (Timer for DCD Turn On Delay)

Register :T6 specifies the time that the modem waits after it raises carrier before it starts looking for data. This register can be set to ignore noise that occurs when DCD is raised in V.23 half-duplex connections. If :T6 is set to zero, the modem waits 256 milliseconds before looking for data. Register :T6 is used only in normal mode V.23 half-duplex connections.

Range

0 to 255 milliseconds

Default

200 milliseconds

:T9 (Primary XON Flow Control Character)

Register :T9 specifies the character used for primary XON flow control on the modem and serial ports. Both modems must use the same primary flow control characters during normal connections. Use the \ Q1 or \ Q4 command (Serial Port Flow Control), and \G1 or \G2 command (Modem Port Flow Control) to specify primary flow control.

Range

0 to 255 (decimal value of an 8-bit ASCII character)

Default

17 (DC1 or 11 hexadecimal)

:T10 (Primary XOFF Flow Control Character)

Register :T10 specifies the character used for primary XOFF flow control on the modem and serial ports. Both modems must use the same primary flow control characters during normal connections. Use the \ Q1 or \ Q4 command (Serial Port Flow Control) options, and \G1 or \G2 command (Modem Port Flow Control) options to specify primary flow control.

Range

0 to 255 (decimal value of an 8-bit ASCII character)

Default

19 (DC3 or 13 hexadecimal)

:T11 (Secondary XON Flow Control Character)

Register :T11 specifies the character used for secondary XON flow control on the modem's serial port. Use the -F1\ Q1 or -F1\ Q4 commands to specify secondary flow control.

Range

0 to 255 (decimal value of an 8-bit ASCII character)

Default

249 (F9 hexadecimal)

:T12 (Secondary XOFF Flow Control Character)

Register :T12 specifies the character used for secondary XOFF flow control on the modem serial port. Use the -F1\ Q1 or -F1\ Q4 commands to specify secondary flow control.

Range

0 to 255 (decimal value of an 8-bit ASCII character)

Default

251 (FB hexadecimal)

:T14 (Connect Message Delay Timer)

Register :T14 specifies the time that the modem waits before or after a connect message before CTS, DSR, or DCD is raised. Use this register setting with the @C0 or @C1 command (CTS, DSR, and DCD Message Control options).

Range

0 to 255 (100-millisecond increments)

Default

0

:T16 (CTS Turn On Delay Timer)

Register :T16 specifies the time that the modem waits before raising CTS after DCD or DSR has been raised in connect mode.

Range

0 to 255 (12.5-millisecond increments)

Default

0

:T17 (V.32/V.32 bis Connection Training Timer)

Register :T17 specifies the time limit for exchanging training sequences when establishing V.32 and V.32 bis connections.

To reduce the time required to establish a connection (but increase the modem's sensitivity to noise on the line), set :T17 to a value less than 28.

To reduce the modem's sensitivity to noise (but lengthen the time required to make a connection), set :T17 to a value greater than 28.

Range

0, 1, or 5 to 32 seconds

Default

0 (use dynamic training sequences, equivalent to a setting of 28)

:T19 (Bit-Mapped Register)

Register :T19 specifies the MNP link control. The register is bit-mapped for the functions listed in Table 74.

:T22 (DSR Timer)

Register :T22 specifies the time that the modem waits before DSR transitions off after DCD or CTS transitions off in disconnect mode. For example, if \D2 (Serial Port DSR/CTS Control) and &C1 (Serial Port DCD Control) are set when DCD and CTS transition off, the modem waits for the time specified by register :T22 before setting DSR off.

Range

0 to 255 (12.5-millisecond increments)

Default

34 (425 milliseconds)

:T23 (Bit-Mapped Register)

Register :T23 is bit-mapped for the functions listed in Table 75.

:T26 (Bit-Mapped Register)

Register :T26 is bit-mapped for the functions listed in Table 76.

Default

0
Note that the default should not be changed except when configuring country codes in modem firmware version 2.2.8 or earlier. (See Step 3 on page 29).

:T89 (PoS Configuration)

Register :T89 is implemented with version 3.2.10. For more information, see "PoS Support," page 71.

Default

0010 (0x2)

Notes:

• Use ITU V.21/V.22.

• Forced Normal Mode at 300/1200.

• Use S9 Register Delay before recognizing Carrier.

• Use 2100 Hz Answerback Tones.

• Bit 1 of :T89 is now defaulted to a 1 (:T89=2). This forces a Normal Mode connection at 300 baud. By turning off this bit, MNP connections will be attempted.

• If the bit is on (answer modem), and the originate modem is set to \N2, no connection will result.

• To support Bell 103 PoS terminals, set :T89 to 7.

• To support V.21 PoS terminals, set :T89 to 6.

• If V.23 is supported and PoS/QUICK 300 is not, NORMAL mode will be forced in the case of a V.23 connection (:T89 has no effect in this case).

:T110 (Select V.8 or V.8 bis Modem Exchange Register)

Default

:t110 = 4 <- V.8bis enable, K56Flex (version 3.2.10 and beyond)

:t110 = 6 <- V.8 enable, K56Flex (version 3.1.30)

:T114 (CT1/PRI Configuration)

Register :T114 is used by 56-kbps modems to configure the modem for CT1 or PRI operation as follows:

• For CT1 operation, set bit 2

• For PRI operation, clear bit 2

:T120 (Answerback Tone Duration)

Register :T120 is implemented with version 3.2.10. For more information, see "PoS Support," page 71.

Default

11001 (0x19, 25 decimal) for 2500 milliseconds of 1650 Hz tone

:T121 (Answerback Tone Configuration for PoS)

Register :T121 is implemented with version 3.2.10. For more information, see "PoS Support," page 71.

Default

11011 (0x1B, 27 decimal) 2700 milliseconds answerback tones

Debugging

The @E command (detailed modem call status) is an unofficially supported modem status and debugging command that can be used by an experienced user to verify the detailed status of the modem during or after a call. The content of this command might change as required to assist in problem resolution. Therefore, the command might produce results that differ from the description in this section.

The @E0 command results in a single-screen display (press any key for the next screen). The @E1 command results in continuous screen display. Press Ctrl-X or Break to cancel the display.

This section provides two sample reports generated by V.34 and 56K modems. For an explanation of the report, see Table 78. Note that some empirical quality data is provided to assist in the interpretation of this measured data, and the fields change with new firmware releases.

A sample of the @E report generated by a V.34 modem (version 2.2.8 firmware) follows:

at@e1
MNP Class 10 V.34/V.FC Modem 
MODEM HW: OEM 2W United States
Firmware Rev 2.2.8/85
Bootstrap Rev 1.0.5
DSP C36 Part/Rev              3035 4241
DSP C58 Part/Rev              3035 2041
NET ADDR:      FFFFFFFFFFFF
Connect Time HH:MM:SS         000:02:01
4 RTS 5 CTS 6 DSR - CD 20 DTR - RI 
Disconnect  Remote -   Local - 14,10,9
CONNECTION STATUS             
Mod Type                      IDLE
TX/RX Spd                     600 600 BPS
TX/RX Spd Mask                   NA  0000 Hex
TX/RX Symbol Rate              2400  2400 Hz
TX/RX Carrier Frequency        1800  1800 Hz
TX/RX Trellis Code States        16    16
TX/RX Nonlinear Encoding        OFF   OFF
TX/RX Precoding                 OFF   OFF
TX/RX Shaping                   OFF   OFF
TX Preemphasis Index              0
TX Lvl Reduction                  0 dB
Secondary Channel               OFF
LINE IMPAIRMENTS              
TX Lvl REG                     - 10 dBm
TX Lvl RAM                     -  0 dB
TX Lvl Reduction                  0 dB
TX Lvl                         - 10 dBm
RX Lvl                         - 16 dBm
Signal/Noise Ratio                0
Signal/Distortion Ratio           0
Eye Quality                    0000 Hex
Lower Band Edge                   0 Hz
Upper Band Edge                   0 Hz
Phase Jitter Freq                 0 Hz
Phase Jitter Amp                0.0 deg
Far Echo Offset (Phase Roll)    0.0 Hz
Far Echo Lvl = 20log(N)-81        0 N
Round Trip Delay                  0 msec
Dropouts > 5dB                    0
RTRNs Initiated                   0
RTRNs Accepted                    0
Rate Changes Initiated            0
Rate Changes Accepted             0
FF Trip/Block Error Rate       0000 Hex
                              
EQM FUNCTION STATUS           
AVG EQM Filter Pole            8A25 Hex
EQM Gain                       8A4E Hex
EQM Offset                     8A77 Hex
AVG EQM Filter Pole            8AA0 Hex
AVG EQM Baud Interval          8AC9 Hex
AVG EQM Sample Size            8AF2 Hex
AVG EQM                        8B1B Hex
EQM Threshold Lvl              8B44 Hex
OK

A sample of the @E report generated by a 56K modem (version 3.1.30 firmware) follows:

at@e1
MNP Class 10 K56flex Modem
MODEM HW: OEM 2W United States
Firmware Rev 3.1.30/85
Bootstrap Rev 3.0.4
DSP C36 Part/Rev              3635 4241
DSP C58 Part/Rev              3635 2041
DSP Controller Rev            0101
DSP Data Pump Rev             0101
NET ADDR:      FFFFFFFFFFFF
Connect Time                  000:00:06
4 RTS 5 CTS 6 DSR 8 CD 20 DTR - RI
 Disconnect  Remote -   Local -
Mod Type                      K56
TX/RX Spd                     56000  31200 BPS
TX/RX Spd Mask                   NA  BFFF Hex
Symbol Rate                    3200 Hz
TX/RX Carrier Freq             1829  1829 Hz
TX/RX States                     16    16
TX/RX NLE                       OFF    ON
TX/RX Precoding                 OFF    ON
TX/RX Shaping                   OFF    ON
TX Preemphasis Index              0
TX Lvl REG                     - 13 dBm
TX Lvl RAM                     -  0 dB
TX Lvl Reduct                     0 dB
TX Lvl                         - 13 dBm
RX Lvl                         - 14 dBm
S/NR                             47
S/DR                              0
 EQM                            1E00 Hex
AVG EQM                        1E0D Hex
Lower/Upper Edge                150  3825 Hz
Phase Jitter Freq               127 Hz
Phase Jitter Amp                0.0 deg
Far Echo Lvl                  24592 N
Round Trip Delay                  0 msec
Dropouts > 5dB                    0
RTRNs Init/Accept                 0     0
RRENs Init/Accept                 0     0
BLER                           0000 Hex
RBS Counter                    000E Hex
Digital Pad Detected           0000
OK

Table 78 provides a description of components of the report. Note that the table does not include self-explanatory fields.

PoS Support

Firmware Version 3.2.10 for K56 digital modems on the Cisco AS5200 and AS5300 platforms incorporates a series of adaptations for PoS quick connects in Europe that are defined best under two sets of modifications. The objective is to enable an immediate V.21 without answer tone for 300 bps PoS and then train up to V.22 with answer tone for 1200 bps PoS. By default, the configuration is locked to 8 bit data, no parity, 1 start, 1 stop bit, and normal mode connections.

Registers :t89, :t120, and :t121 have been allocated to enable 300/1200 quick connections, error correction, pause for DCD to be true, and tone duration timers.

An incoming call will be answered and the answer modem sends out 1650 Hz immediately. The PoS device can send back 980 Hz if configured to do so. Note Bit 3 of :t89 in the section ".

The answer modem detects the data carrier--in this case within 5 milliseconds--at which time the PoS device initiates the transaction request. If the device calling is not a quick connect V.21 device then the 1650 Hz timer will expire (duration of 1650 Hz declared in :t120) and the answer modem will then train up for 1200 bps and send out 2100 Hz answerback tones (duration of answerback tones declared in :t121). The standard answerback period of 3 seconds (+/- 20%) is modifiable by :t121.

Two new AT commands for the command parser enable spawning early SVC circuit building while the modems are engaged in the modulation handshake. This assures that there will be no latency for SVC set up and network overhead. These new commands, &C3 and \D4, have been utilized to lower CTS and raise DCD upon incoming call detection and going off-hook.

:&C3\D4 Definition

The &C3 and \D4 AT commands are incorporated to permit aggressive SVC circuit building while the modems handshake. The X.25 SVC circuit is spawned upon recognition of DCD active at the end of a modem handshake when the modem goes to data mode.

\D4 permits ITU signal control for DSR/CTS. This is used with the command &C3 to enable the following sequence:

Step 1 Incoming Call Detection is set to Modem Off-Hook.

Step 2 CTS is lowered to the host interface in order to disable the host transmit, assuring that no data will be sent to the modems during training, and that any data sent from the network host before modem training is complete will be held in the tx queue and forwarded when CTS is presented active again.

Step 3 Raise DCD to spawn the PoS SVC circuit building to the remote authorization host.

Step 4 Send back the 1650 Hz and/or 2100 Hz train up answer sequence and establish carrier and data mode with the external dialing device.

Step 5 CTS is presented as active to enable the host transmit and forwards the host transaction responses.

The early circuit build or SVC spawning will work well with or without 1200/2400 fast-transaction support. The training up from 300 to 1200 feature is absolutely essential for Europe, as the 300 bps PoS devices do not handle the 2100 Hz answerback tones, and they will fail and disconnect if a traditional handshake and downspeed shift is attempted.

For help with questions or problems, contact Cisco Systems as described in the section "Cisco Connection Online" at the end of this document.

PoS Field Applications

The PoS feature is deployed with two main types of PoS devices. One device is a low-speed, instant connect V.21 terminal, which dictates that the modems train up, not down as would typically be the case with Central Site Modems.

The actual initialization string for a European client could be exactly as described in the following example. Note that the string includes the country code specific profile.

Caution You cannot apply a country code -IxZ command in the PoS modemcap -- the PoS features will either be ignored or removed with the associated country reset. The specialized PoS train up and quick-connect features are ITU (V.21/V.22) specific. This dictates that you will remove any country code modemcap and apply any country specific requirements as part of your PoS modemcap.

The early circuit spawning feature available with \D4&C3 is completely independent of any ITU or Bell mode and can be used to accelerate PoS transaction times to pre-build sessions as the modems complete handshake sequences.

The &C3 command will never be used without the \D4 command. The two commands are interlocked for the PoS feature. For more information, see "\Dn (Serial Port DSR/CTS Control)," page 38 and "&Cn (Serial Port DCD Control)," page 22.

Example of Modemcap Creation, Assignment, Audit

Enter the router configuration mode and create a global modemcap as follows:

access server #conf t
Enter configuration commands, one per line.  End with CNTL/Z.
access server (config)#modemcap edit your_config factory &f&d0%d2@c0b0%m0\n0 
access server (config)#modemcap edit your_config misc
%u0%g1%b1200%u1:t89=14:t121=015:t51=14\d4&c3
access server (config)#li 11
access server (config-line)#mod auto type your_config
access server (config-line)#exi
access server (config)#exi

With the debug command debug confmodem, audit the resultant profile as follows:

access server #deb confmodem
Modem Configuration Database debugging is on
access server #cle li 11
[confirm]
[OK]
access server #
Dec 11 15:58:20 PST: TTY11: Line reset by "Exec"
Dec 11 15:58:20 PST: TTY11: Modem: IDLE->HANGUP
Dec 11 15:58:20 PST: TTY11: dropping DTR, hanging up
Dec 11 15:58:20 PST: tty11: Modem: HANGUP->IDLE
Dec 11 15:58:25 PST: TTY11: restoring DTR
Dec 11 15:58:26 PST: TTY11: autoconfigure probe started
Dec 11 15:58:26 PST: TTY11: Modem command:
--AT&f&d0%d2@c0b0%m0\n0%u0%g1%b1200%u1:t89=14:t121=015:t51=14\d4&c3--

Cisco Connection Online

Cisco Connection Online (CCO) is Cisco Systems' primary, real-time support channel. Maintenance customers and partners can self-register on CCO to obtain additional information and services.

Available 24 hours a day, 7 days a week, CCO provides a wealth of standard and value-added services to Cisco's customers and business partners. CCO services include product information, product documentation, software updates, release notes, technical tips, the Bug Navigator, configuration notes, brochures, descriptions of service offerings, and download access to public and authorized files.

CCO serves a wide variety of users through two interfaces that are updated and enhanced simultaneously: a character-based version and a multimedia version that resides on the World Wide Web (WWW). The character-based CCO supports Zmodem, Kermit, Xmodem, FTP, and Internet e-mail, and it is excellent for quick access to information over lower bandwidths. The WWW version of CCO provides richly formatted documents with photographs, figures, graphics, and video, as well as hyperlinks to related information.

You can access CCO in the following ways:

• WWW:  http://www.cisco.com

• WWW:  http://www-europe.cisco.com

• WWW:  http://www-china.cisco.com

• Telnet:  cco.cisco.com

• Modem:  From North America, 408 526-8070; from Europe, 33 1 64 46 40 82. Use the following terminal settings: VT100 emulation; databits: 8; parity: none; stop bits: 1; and connection rates up to 28.8 kbps.

For a copy of CCO's Frequently Asked Questions (FAQ), contact cco-help@cisco.com. For additional information, contact cco-team@cisco.com.

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