|
|
January 5, 2000
This document describes AT commands and S and :T registers for the following universal access server modules:
See "V.90 56K AT Command Set Support," for specific information pertaining to the AT command set which supports the K56flex and V.90 speeds. These commands are in support of firmware version 5.x.xx (use the show modem version command).
![]() |
Note Except where noted, this document lists defaults and descriptions for the latest firmware, that is version 3.2.20 (for 56K 12-port modules) and version 2.3.6 (for V.34 12-port modules). For defaults for previous firmware versions, see the universal access server modem firmware release notes, which are available on the World Wide Web at http://www.cisco.com, http://www-china.cisco.com, or http://www-europe.cisco.com. |
![]() |
Note For Point of Sale (PoS) support, make sure that the 12-port board is running firmware version 3.2.10 or later (use the show modem version command). |
![]() |
Note Customers using Cisco IOS Release 12.0(4)XI1 or higher will be prompted to use the Service Processing Element (SPE) command instead of the modem-pool command to download code. The modem-pool command will no longer be available, and the existing modem firmware configurations in the router will be converted to the new spe command format. See the Cisco document, SPE and Firmware Download Enhancements at the following URL for more information about the spe command: http://www.cisco.com/univercd/cc/td/doc/product/software/ios120/120newft/120t/120t7/spe1206t.htm |
If you have questions or need help, refer to the last section "Cisco Connection Online" for further information.
This document contains the following sections:
Keep in mind the following guidelines when you send AT commands to a modem:
| Step | Command | Purpose |
|---|---|---|
| 1 | access server Password: <password> access server | Enter privileged EXEC (enable) mode. Enter the password. You have entered privileged EXEC mode when the access server |
| 2 | access server access server | Enter global configuration mode. You have entered global configuration mode when the |
| 3 | access server(config)# line 1 access server(config-line)# | Enter line configuration mode. In this example, line 1 is specified. You have entered line configuration mode when the |
| 4 | access server(config-line)# modem at-mode-permit | Configure a manageable modem to permit a direct-connect session. |
| 5 | access server access server# %SYS-5-CONFIG_I: Configured from console by console <Return> access server# | Return to privileged EXEC mode.
When this message appears, press Return to get the |
| 6 | | Enter a direct-connect session with a modem. In this example, a direct-connect session is established with the modem in slot 1, port 1. Enter the modem slot number first, followed by the modem port number. Now you are in AT command mode and can enter the AT commands described in this document. |
| 7 | <Ctrl> <c> access server# | When you are finished entering AT commands, press Ctrl-C to exit AT command mode and return to privileged EXEC mode. |
![]() |
Note ATA, ATO, ATD, and all dial modifiers are not valid in direct-connect sessions. |
![]() |
Note The default for the #E command is #E1, which means that the escape code sequence is disabled in answer mode. For more information, refer to the section, "# Character Command Set,". |
This section describes modem commands that begin with an alphabetic (A to Z) character.
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.
Reexecutes the last command one time. A/ is not preceded by the AT prefix and is not followed by a Return.
Informs the modem that commands are being sent to it. AT must precede all other commands except A/ and +++.
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.
| Command | Meaning |
|---|---|
B0 | ITU V.22 standard at 300 and 1200 bps, international default1 |
B1 | Bell 212A standard at 300 and 1200 bps, USA default1 |
| 1Default is determined by country setting. |
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.
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.
| Modifier | Meaning |
|---|---|
^A | Performs link negotiation at 4800 bps for this connection only. This dial modifier is equivalent to the *H2 command (link negotiation at 4800 bps). |
J | Performs link negotiation at 1200 bps for this connection only. This dial modifier is equivalent to the *H1 command (link negotiation at 1200 bps). |
K | Adjusts the power level for a single cellular connection.This option is used for modems attached to cellular interfaces. |
L | Redials the last telephone number. |
Dials in Link Access Procedure for Modem (LAPM) Mode for this connection only. | |
Nn | Dials an alternate stored number. This modifier must follow the last character in a dial string. If the modem fails to make a connection, the Nn modifier dials alternate telephone number n (where n is a number between 1 and 9) stored in the directory by the &Z or \Pn command (Store Telephone Number). If you do not enter a value for n, the modem dials the first stored entry. For example, to dial the third stored telephone number as an alternate telephone number, enter the following command and press Return: ATD 55554321N3 The Nn modifier can also be stored in the directory at the end of a dial string. If you do not specify a value for n and the modem fails to make a connection, it dials the number in the next position, even if it is null. Stored number 1 follows stored number 9. For example, to store a telephone number and an alternate number in directory entry 4, enter the following command and press Return: AT\P4 5551234N3 |
Dials in LAPM mode for this connection only with fallback to normal mode. | |
Dials a number in answer mode when calling an originate-only modem. The modifier must follow the last character in the dial string. For example, to dial the telephone number 5552345 in answer mode, enter the following command and press Return: ATD 5552345R | |
Dials the telephone number stored as entry 1 with the &Z or \P1 command. The telephone number is displayed as it is dialed. The S modifier must immediately follow D in the dial command. You cannot add the S modifier to the phone number stored in the first directory position. For example, to dial the first stored telephone number, enter the following command and press Return: ATDS | |
Tone-dials the number. The last P or T dial modifier used remains in effect until you enter a new P or T modifier or reset the modem. You can combine P and T dial modifiers within a dial string. For example, to pulse-dial a local telephone number and tone-dial an access code and telephone number, enter the following command and press Return: ATD P12345 T335 6789 | |
Dials in direct mode. The U modifier overrides the current operating mode and dials in direct mode for that connection only. For example, enter the following command and press Return: ATD 12345U | |
Dials in LAPM mode with fallback to MNP for this connection only. For example, enter the following command and press Return: ATD 12345V | |
Waits for dial tone before dialing. The W modifier is inserted between digits in a dial string. The modem then waits for the time specified in register S7. If it receives a dial tone before the time delay expires, it continues dialing; otherwise, it returns NO DIALTONE and hangs up. For example, enter the following command and press Return: ATD 12345 W 67890 | |
Dials in autoreliable mode for this connection only. For example, enter the following command and press Return: ATD 12345X | |
Dials in MNP reliable mode for this connection only. For example, enter the following command and press Return: ATD 12345Y | |
Dials in normal mode for this connection only. For example, enter the following command and press Return: ATD 12345Z | |
/n | Dials one of the nine telephone numbers stored in the directory by the &Z or \Pn command (where n is a number between 1 and 9). The telephone number is displayed as it is dialed. |
Pauses during dialing for the time specified in register S8 before dialing the next digit. Use more than one comma for a longer pause. For example, use the comma when you need to dial 9 and then wait for another dial tone before dialing an outside line: ATD 9,,5552345 | |
Waits for quiet answer before dialing. This modifier is inserted between characters in a dial string. The modem waits for the time specified in register S7 for at least one ring, followed by 5 seconds of silence, before acting on the next character in the dial string. If the modem does not detect this sequence, it returns a NO ANSWER result code and hangs up. Use this modifier when the system you are calling does not provide a dial tone. For example: ATD 5551234 @ 43210 | |
Sets the modem on-hook for one-half second and then back off-hook. This is equivalent to depressing the switch-hook button on your telephone. | |
Returns to command state after dialing. Add this modifier to the end of a dial string. The modem remains in command state after it dials the digits preceding the semicolon, so that you can enter dial strings longer than 98 characters. Each dial command except the last one must end with a semicolon. After the final dial command is entered, the modem tries to establish a connection. To abort dialing before attempting to establish a connection, enter the H command (Hang Up). For example: ATD 9,12345; OK ATD 78989 @ 12345 W 344 |
Configures the modem to echo commands to the workstation. Table 4 lists command options.
E1
| Command | Meaning |
|---|---|
E0 | Disables echoing commands to the workstation |
E1 | Enables echoing commands to the workstation |
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.
Displays modem information and results of checksum tests on firmware. Table 5 lists identification command options.
| Command | Meaning |
|---|---|
I0 | Displays the four-digit modem product code |
I1 | Runs a checksum on firmware ROM and displays the three-digit result |
I2 | Runs a checksum on firmware ROM and displays the checksum status |
I3 | Displays the modem name and revision level. |
Sets the modem to connect state. Table 6 lists command options.
| Command | Meaning |
|---|---|
O0 | Enters connect state. |
O1 | Begins an equalizer retrain sequence when operating at 2400 bps or higher and then returns to connect state. Use the O1 command to reduce loss of equalization because of excessive bit error rates. |
Configures the modem to send result and status codes, such as OK, BUSY, and RING, to your workstation. Table 7 lists command options.
Q0
| Command | Meaning |
|---|---|
Q0 | Enables output of result codes. |
Q1 | Disables output of result codes. |
Q2 | Disables only answer mode result codes. Status report messages are not affected. |
Displays the contents of S register n (where n is a decimal number).
0 to 27
S0
Sets the current dialing mode to tone. This is the default dialing mode.
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.
V1
| Command | Meaning |
|---|---|
V0 | Sends short form result codes |
V1 | Sends long form result codes |
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.
W2
| Command | Meaning |
|---|---|
W0 | Displays serial port connect messages |
W1 | Displays serial port connect messages |
W2 | Displays modem port connect messages |
Selects the extended result code format sent to the workstation. Table 10 lists command options.
The following commands also affect the result code format:
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.
X4
![]() |
Note The W dial modifier causes a wait for dial tone regardless of the Xn command setting. |
| Command | Meaning |
|---|---|
X0 | Sends a connect result code when a connection is established. The modem ignores dial tone and busy signals. |
X1 | Sends a connect result code reflecting the bps rate when a connection is established. The modem ignores dial tone and busy signals. |
X2 | Sends a connect result code reflecting the bps rate when a connection is established. The modem sends a NO DIALTONE result code if dial tone is not detected within 5 seconds of a dial attempt. The modem ignores busy signals. |
X3 | Sends a connect result code reflecting the bps rate when a connection is established. The modem sends a BUSY result code if a busy signal is detected. The modem ignores dial tone. |
X4 | Sends a connect result code reflecting the bps rate when a connection is established. The modem sends a NO DIALTONE result code if dial tone is not detected within 5 seconds of a dial attempt. The modem sends a BUSY result code if a busy signal is detected. |
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:
Y0
| Command | Meaning |
|---|---|
Y0 | Disables long space disconnect on receipt of an H command. The normal break signal is sent. |
Y1 | Enables long space disconnect on receipt of an H command. Y1 must be set on both modems for this command to take effect. |
This section describes modem commands that begin with a caret (^) character.
Copies new firmware from a computer file to the modem's Flash memory.
Displays the modem's current Flash memory bootstrap revision.
This section describes modem commands that begin with a dollar ($) character.
Sets the serial port rate to n bps.
300, 600, 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200 bps
$B115200
Runs power-up diagnostics.
This section describes modem commands that begin with a percent (%) character.
![]() |
Note Modifications have been made to certain percent (%) AT commands as a result of enhancements made to the firmware version 5.0.4. Changes affect commands %B, %Gn, %G1, and %M. |
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. |
0 to 127 (ASCII decimal)
%A0 (autoreliable fallback character is disabled)
Sets the modem port data rate. Downshifting can still occur.
![]() |
Note The user must always set %M before setting the %B option. Setting %M results in %B getting set to the maximum baud rate for that modulation. With AT%G0, setting %M will have no effect on %B. With AT%G1, setting %M will cause the %B to be set to the maximum value in that modulation. See %M (Modulation). |
The %Bn command is affected by the following %Gn command (Independent Serial/Modem Port Speed) options:
300, 600, 1200, 2400, 4800, 7200, 9600, 12000, 14400, 16800, 19200, 21600, 24000, 26400, 2800, 28800, 29333, 30666, 31200, 32000, 33333, 34000, 34666, 33600, 36000, 37333, 38000, 38666, 40000, 41333, 42000, 42666, 44000, 45333, 46000, 46666, 48000, 49333, 50000, 50666, 52000, 53333, 54000, 54666, 56000 bps
![]() |
Note Includes V.90 speeds |
%B33600 for V.34 modems
%B56000 for 56 kbps modems
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:
%C3
| Command | Meaning |
|---|---|
%C0 | Disables data compression. |
%C1 | Enables MNP Class 5 data compression only. |
%C2 | Enables V.42 bis compression only. |
%C3 | Enables V.42 bis compression and MNP Class 5 Data Compression. The modem matches the capability of the remote modem. |
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.
0 to 255 seconds
%D0
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.
%E1
| Command | Meaning |
|---|---|
%E0 | Disables the automatic retrain sequence. Use the O1 command (Enter Connect State) to force the retrain sequence when %E0 is set. |
%E1 | Enables the automatic retrain sequence at 2400 bps or higher. |
Configures the modem for V.23 mode. Table 14 lists the V.23 command options.
%F0
| Command | Meaning |
|---|---|
%F0 | Allows multiprotocol answering; disables V.23 mode on the originate modem |
%F1 | 75-bps transmit, 1200-bps receive (split speed) V.23 operation |
%F2 | 1200-bps transmit, 75-bps receive (split speed) V.23 operation |
%F3 | 1200-bps transmit, 1200-bps receive (half duplex) V.23 operation |
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.
%G0
| Command | Meaning |
|---|---|
%G0 | Updates the serial and modem port speeds each time an AT command is entered. The serial port speed determines the modem port speed. |
%G1 | Updates the modem port speed only when a %Bn (Modem Port Bps Rate) command is entered. |
The following tables list command strings for setting modem port speeds:
| Protocol | %G0 | %G1 |
|---|---|---|
V.21 (300 bps) | Using B0 at 300 bps | B0%B300 |
Bell 103 (300 bps) | Using B1 at 300 bps | B1%B300 |
V.22 (600 bps) | At 600 bps | %B600 |
V.22 (1200 bps) | Using B0 at 1200 bps | B0%B1200 |
Bell 212A (1200 bps) | Using B1 at 1200 bps | B1%B1200 |
V.22 bis (2400 bps) | At 2400 bps | %B2400 |
V.32 (4800 bps) | At 4800 bps | %B4800 |
V.32 (9600 bps) | At 9600 bps | %B9600 |
V.32 bis (14400 bps) | At 14400 bps | %B14400 |
V.FC (38800 bps) | At 28800 bps | %B28800 |
| When %M2 or %M3 Is Set: | |
|---|---|
| V.34 Speed | %G1 |
2400 bps | %B24001 |
4800 bps | %B4800 |
7200 bps | %B7200 |
9600 bps | %B9600 |
12000 bps | %B12000 |
14400 bps | %B14400 |
16800 bps | %B16800 |
19200 bps | %B19200 |
21600 bps | %B21600 |
24000 bps | %B24000 |
26400 bps | %B26400 |
28800 bps | %B28800 |
31200 bps | %B31200 |
33600 bps | %B33600 |
| 1In answer mode, this will result in V.22 bis connection. |
| When %M3 Is Set: | ||
|---|---|---|
| 56 kbps Speed | %G1 | |
| 32000 bps | %B32000 |
| 34000 bps | %B34000 |
| 36000 bps | %B36000 |
| 38000 bps | %B38000 |
| 40000 bps | %B40000 |
| 42000 bps | %B42000 |
| 44000 bps | %B44000 |
| 46000 bps | %B46000 |
| 48000 bps | %B48000 |
| 50000 bps | %B50000 |
| 52000 bps | %B52000 |
| 54000 bps | %B54000 |
| 56000 bps | %B56000 |
| When %M4 Is Set: | ||
|---|---|---|
| 56 kbps Speed | %G1 | |
| 28000 bps | %B2800 |
| 29333 bps | %B29333 |
| 30666 bps | %B30666 |
| 32000 bps | %B32000 |
| 33333 bps | %B33333 |
| 34000 bps | %B34000 |
| 34666 bps | %B34666 |
| 36000 bps | %B36000 |
| 37333 bps | %B37333 |
| 38000 bps | %B38000 |
| 38666 bps | %B38666 |
| 40000 bps | %B40000 |
| 41333 bps | %B41333 |
| 42000 bps | %B42000 |
| 42666 bps | %B42666 |
| 44000 bps | %B44000 |
| 56 kbps Speed | %G1 | |
| 45333 bps | %B45333 |
| 46000 bps | %B46000 |
| 46666 bps | %B46666 |
| 48000 bps | %B48000 |
| 49333 bps | %B49333 |
| 50000 bps | %B50000 |
| 50666 bps | %B50666 |
| 52000 bps | %B52000 |
| 53333 bps | %B53333 |
| 54000 bps | %B54000 |
| 54666 bps | %B54666 |
| 56000 bps | %B56000 |
Configures the modem to use speed matching when establishing a connection. Table 18 lists command options.
%L1
| Command | Meaning |
|---|---|
%L0 | Provides partial speed matching |
%L1 | Enables speed matching |
%L2 | Disables speed matching |
%L3 | Enables V.8 automode with fallback to ITU-T1 automode |
%L4 | Enables V.8 automode only |
| 1International Telecommunications Union Telecommunication Standardization sector. |
The following tables list connections the modem can establish with %L1 or %L3 set.
| Mode Setting on Originating Access Server 56K Modem | Mode Setting on Answering Modem | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Bell 103 | Bell 212A | V.22[b] | V.22[a] | V.22 bis | V.32 | V.32 bis | V.FC | V.34 | K56flex/ V.90 | |
K56flex (32000-56000) | - | V.22[a] | - | - | V.22 bis | V.32 | V.32 bis | V.FC | V.34 | K56flex1 |
V.34 annex 12- (31200-33600) |
| V.22[a] | - | - | V.22 bis | V.32 | V.32 bis | V.FC | V.34 | V.34 |
V.34 (2400-28800) | - | V.22[a] | - | V.22[a] | V.22 bis | V.32 | V.32 bis | V.FC | V.34 | V.34 |
V.FC (14400-28800) | - | V.22[a] | - | V.22[a] | V.22 bis | V.32 | V.32 bis | V.FC | V.FC | V.FC2 |
V.32 bis (4800-14400) | - | V.22[a] | - | V.22[a] | V.22 bis | V.32 | V.32 bis | V.32 bis | V.32 bis | V.32 bis |
V.32 (4800-9600) | - | V.22[a] | - | V.22[a] | V.22 bis | V.32 | V.32 | V.32 | V.32 | V.32 |
V.22 bis (2400) | - | V.22[a] | - | V.22[a] | V.22 bis | V.22 bis | V.22 bis | V.22 bis | V.22 bis | V.22 bis |
V.22[a] (1200) | - | V.22[a] | - | V.22[a] | V.22[a] | V.22[a] | V.22[a] | V.22[a] | V.22[a] | V.22[a] |
V.22[b] (600) | - | - | V.22[b] | - | - | - | - | - | - | - |
V.23[a] (xmt 75) | - | - | - | V.23[b] | V.23[b] | V.23[b] | V.23[b] | V.23[b] | V.23[b] | V.23[b] |
V.23[b] (xmt 1200) | - | - | - | - | - | - | - | - | - | - |
V.21(75-300) | - | V.22[a] | - | V.21 | V.21 | V.21 | V.21 | V.21 | V.21 | V.21 |
Bell 212A (1200) | Bell 212A | Bell 212A | - | V.22[a] | V.22[a] | V.22[a] | V.22[a] | V.22[a] | V.22[a] | V.22[a] |
Bell 103 (300) | Bell 103 | Bell 103 | - | Bell 103 | Bell 103 | Bell 103 | Bell 103 | Bell 103 | Bell 103 | Bell 103 |
| Mode Setting on Originating Modem | Mode Setting on Answering Access Server 56K Modem | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Bell 103 | Bell 212A | V.22[b] | V.22[a] | V.22 bis | V.32 | V.32 bis | V.FC | V.34 | K56flex/ V.90 | |
K56flex (32000-56000) | - | - | - | V.22[a] | V.22 bis | V.32 | V.32 bis | V.FC | V.34 | K56flex |
V.34 annex 12 (31200-33600) | - | - | - | V.22[a] | V.22 bis | V.32 | V.32 bis | V.FC | V.34 | V.34 |
V. 34 (2400-28800) | - | - | - | V.22[a] | V.22 bis | V.32 | V.32 bis | V.FC | V.34 | V.34 |
V.FC (14400-28800) | - | V.22[a] | - | V.22[a] | V.22 bis | V.32 | V.32 bis | V.FC | V.FC | V.FC |
V.32 bis (4800-14400) | - | V.22[a] | - | V.22[a] | V.22 bis | V.32 | V.32 bis | V.32 bis | V.32 bis | V.32 bis |
V.32 (4800-9600) | - | V.22[a] | - | V.22[a] | V.22 bis | V.32 | V.32 | V.32 | V.32 | V.32 |
V.22 bis (2400) | - | V.22[a] | - | V.22[a] | V.22 bis | V.22 bis | V.22 bis | V.22 bis | V.22 bis | V.22 bis |
V.22[a] (1200) | - | V.22[a] | - | V.22[a] | V.22[a] | V.22[a] | V.22[a] | V.22[a] | V.22[a] | V.22[a] |
V.22[b] (600) | - | - | V.22[b] | - | - | - | - | - | - | - |
V.23[a] (xmt 75) | - | - | - | V.23[b] | V.23[b] | V.23[b] | V.23[b] | V.23[b] | V.23[b] | V.23[b] |
V.23[b] (xmt 1200) | - | - | - | - | - | - | - | - | - | - |
V.21(75-300) | - | V.22[a] | - | V.21 | V.21 | V.21 | V.21 | V.21 | V.21 | V.21 |
Bell 212A (1200) | Bell 212A | Bell 212A | - | V.22[a] | V.22[a] | V.22[a] | V.22[a] | V.22[a] | V.22[a] | V.22[a] |
Bell 103 (300) | Bell 103 | Bell 103 | - | Bell 103 | Bell 103 | Bell 103 | Bell 103 | Bell 103 | Bell 103 | Bell 103 |
| Mode Setting on Originating Access Server V.34 Modem | Mode Setting on Answering Modem | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Bell 103 | Bell 212A | V.22[b] | V.22[a] | V.22 bis | V.32 | V.32 bis | V.FC | V.34 | K56flex/ V.90 | |
V.34 annex 12 (31200-33600) |
|
|
|
| V.22 bis | V.32 | V.32 bis | V.FC | V.34 | V.34 |
V. 34 (2400-28800) |
|
|
| V.22[a] | V.22 bis | V.32 | V.32 bis | V.FC | V.34 | V.34 |
V.FC (14400-28800) | - | V.22[a] | - | V.22[a] | V.22 bis | V.32 | V.32 bis | V.FC | V.FC | V.FC1 |
V.32 bis (4800-14400) | - | V.22[a] | - | V.22[a] | V.22 bis | V.32 | V.32 bis | V.32 bis | V.32 bis | V.32 bis |
V.32 (4800-9600) | - | V.22[a] | - | V.22[a] | V.22 bis | V.32 | V.32 | V.32 | V.32 | V.32 |
V.22 bis (2400) | - | V.22[a] | - | V.22[a] | V.22 bis | V.22 bis | V.22 bis | V.22 bis | V.22 bis | V.22 bis |
V.22[a] (1200) | - | V.22[a] | - | V.22[a] | V.22[a] | V.22[a] | V.22[a] | V.22[a] | V.22[a] | V.22[a] |
V.22[b] (600) | - | - | V.22[b] | - | - | - | - | - | - | - |
V.23[a] (xmt 75) | - | - | - | V.23[b] | V.23[b] | V.23[b] | V.23[b] | V.23[b] | V.23[b] | V.23[b] |
V.23[b] (xmt 1200) | - | - | - | - | - | - | - | - | - | - |
V.21(75-300) | - | V.22[a] | - | V.21 | V.21 | V.21 | V.21 | V.21 | V.21 | V.21 |
Bell 212A (1200) | Bell 212A | Bell 212A | - | V.22[a] | V.22[a] | V.22[a] | V.22[a] | V.22[a] | V.22[a] | V.22[a] |
Bell 103 (300) | Bell 103 | Bell 103 | - | Bell 103 | Bell 103 | Bell 103 | Bell 103 | Bell 103 | Bell 103 | Bell 103 |
| 1If V.FC modulation is supported in client modems. If not, expected modulation is V.32 bis. |
| Mode Setting on Originating Modem | Mode Setting on Access Server V.34 Answering Modem | ||||||||
|---|---|---|---|---|---|---|---|---|---|
| Bell 103 | Bell 212A | V.22[b] | V.22[a] | V.22 bis | V.32 | V.32 bis | V.FC | V.34 | |
K56flex (32000-56000) |
|
|
|
| V.22 bis | V.32 | V.32 bis | V.FC | V.34 |
V.34 annex 12 (31200-33600) |
|
|
|
| V.22 bis | V.32 | V.32 bis | V.FC | V.34 |
V. 34 (2400-28800) |
|
|
| V.22[a] | V.22 bis | V.32 | V.32 bis | V.FC | V.34 |
V.FC (14400-28800) | - | V.22[a] | - | V.22[a] | V.22 bis | V.32 | V.32 bis | V.FC | V.FC |
V.32 bis (4800-14400) | - | V.22[a] | - | V.22[a] | V.22 bis | V.32 | V.32 bis | V.32 bis | V.32 bis |
V.32 (4800-9600) | - | V.22[a] | - | V.22[a] | V.22 bis | V.32 | V.32 | V.32 | V.32 |
V.22 bis (2400) | - | V.22[a] | - | V.22[a] | V.22 bis | V.22 bis | V.22 bis | V.22 bis | V.22 bis |
V.22[a] (1200) | - | V.22[a] | - | V.22[a] | V.22[a] | V.22[a] | V.22[a] | V.22[a] | V.22[a] |
V.22[b] (600) | - | - | V.22[b] | - | - | - | - | - | - |
V.23[a] (xmt 75) | - | - | - | V.23[b] | V.23[b] | V.23[b] | V.23[b] | V.23[b] | V.23[b] |
V.23[b] (xmt 1200) | - | - | - | - | - | - | - | - | - |
V.21(75-300) | - | V.22[a] | - | V.21 | V.21 | V.21 | V.21 | V.21 | V.21 |
Bell 212A (1200) | Bell 212A | Bell 212A | - | V.22[a] | V.22[a] | V.22[a] | V.22[a] | V.22[a] | V.22[a] |
Bell 103 (300) | Bell 103 | Bell 103 | - | Bell 103 | Bell 103 | Bell 103 | Bell 103 | Bell 103 | Bell 103 |
Use the %L0 or %L2 command options on both originating and answering modems to restrict the connection speed. Table 23 lists connection speeds using the %L0 partial speed matching option. Table 23 lists connections speeds using the %L2 speed matching disabled option. If %L2 is set, the modem speed matches the closest possible connection speed.
| Modem Speed | Possible Connection Speed |
|---|---|
300 | 300 |
600 | 600 |
200 | 1200 |
2400 | 1200, 2400 |
4800 | 4800 |
7200 | 4800, 7200 |
9600 | 4800, 7200, 9600 |
12000 | 4800, 7200, 9600, 12000 |
14400 | 4800, 7200, 9600, 12000, 14400 |
16800 | 14400, 16800 |
19200 | 14400, 16800, 19200 |
21600 | 14400, 16800, 19200, 21600 |
24000 | 14400, 16800, 19200, 21600, 24000 |
26400 | 14400, 16800, 19200, 21600, 24000, 26400 |
28800 | 14400, 16800, 19200, 21600, 24000, 26400, 28800 |
31200 | 14400, 16800, 19200, 21600, 24000, 26400, 28800, 31200 |
33600 | 14400, 16800, 19200, 21600, 24000, 26400, 28800, 31200, 33600 |
| Modem Speed | Possible Connection Speed |
|---|---|
300 | 300 |
600 | 600 |
1200 | 1200 |
2400 | 2400 |
4800 | 4800 |
7200 | 7200 |
9600 | 9600 |
12000 | 12000 |
14400 | 14400 |
16800 | 16800 |
19200 | 19200 |
21600 | 21600 |
24000 | 24000 |
26400 | 26400 |
28800 | 28800 |
31200 | 31200 |
33600 | 33600 |
This command is used to set the upper modulation used in connections. Setting %M results in %B getting set to the maximum baud rate for that modulation.
Example: With AT%G0, setting %M will have no effect on %B. With AT%G1, setting %M will cause the %B to be set tot he maximum value in that modulation.
This command is used to set the upper modulation used in connections. Table 25 lists command options.
%M2 for V.34 modules
%M3 for 56 kbps modules (version 3.x.xx)
%M4 for V.90 56 kbps modules (version 5.x.xx)
![]() |
Note For specific AT command information pertaining to the V.90 interaction of %M and %B, see "V.90 56K AT Command Set Support". |
| Command | Meaning |
|---|---|
%M0 | Disables, V.34, and K56flex modulations V.32 bis, 14.4 kbps maximum |
%M11 | Disables V.34 and K56flex modulations V.FC, 28.8 kbps maximum |
%M2 | Disables K56flex modulation V.34, 33.6 kbps maximum |
%M3 | Enables all modulation modes, including K56flex K56flex, 56 kbps maximum |
%M4 | Enables all modulation modes, including V.90 V.90, 56 kbps maximum |
| 1%M1 is not supported for 56K modems. |
Displays the contents of modem S and :T registers as a table of values in decimal and hexadecimal format. Table 26 lists command options.
| Command | Meaning |
|---|---|
%R0 | Displays the contents of all S registers as decimal and hexadecimal integers in tabular format |
%R1 | Displays the contents of all :T registers as decimal and hexadecimal integers in tabular format |
The following display provides an example of the %R command:
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
Sets the serial port speed. Table 27 lists command options.
%U1
| Command | Meaning |
|---|---|
%U0 | Allows the current serial port speed to be changed to any other speed. This option is not required for speeds of 19200 bps and lower. |
%U1 | Always keeps the current serial port speed. You must enter %U1 each time you change the serial port speed. |
%U2 | Allows the current serial port speed to be changed from any speed. |
Displays the modem firmware version and country code. Table 28 lists command options. (For country code listings, see Table 38.)
%V1
| Command | Meaning |
|---|---|
%V1 | Provides detail to the X.X.X level, for example (note country code of 85, which is USA: at%v1 |
%V0 | Provides detail to the X.X level, for example (note country code of 85, which is USA: at%v1 MNP Class 10 K56flex Modem Rev 3.1/85 |
This section describes modem commands that begin with an ampersand (&) character.
Controls the Data Carrier Detect (DCD) signal level. Use this command if your workstation requires DCD to be off at certain times. Table 29 lists command options. See also the \Dn command.
&C1
| Command | Meaning |
|---|---|
&C0 | DCD is always on. |
&C1 | DCD follows the state of carrier from the remote system and turns on after the connect message. |
&C2 | DCD is on except momentarily at disconnect. |
&C31 | DCD goes active at the end of a modem handshake when the modem goes to data mode. |
| 1Implemented on version 3.2.10. &C3 must never be used without \D4 (see "). For more information, see "PoS Support,". |
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 30 lists command options.
&D3
| Command | Meaning |
|---|---|
&D0 | Ignores DTR. DTR is not needed for autoanswer. |
&D1 | Enters command state on detecting on-to-off transition of DTR. DTR is not needed for autoanswer. |
&D2 | Sets the modem on-hook when detecting an on-to-off transition of DTR and prepares the serial port to accept an AT command at any speed. DTR is needed for autoanswer. |
&D3 | Sets the modem on-hook and resets when detecting an on-to-off transition of DTR and prepares the serial port to accept an AT command at any speed. DTR is needed for autoanswer. |
Restores the factory default configuration. Stored telephone numbers are not cleared.
Sets the guard tone frequency on the answering mode. Table 31 lists command options.
&G0
| Command | Meaning |
|---|---|
&G0 | Disables the guard tone |
&G1 | Sets the guard tone on the answering modem to 550 Hz |
&G2 | Sets the guard tone on the answering modem to 1800 Hz |
Sets the ratio of off-hook (make) to on-hook (break) time that the modem uses for pulse dialing. Table 32 lists command options.
&P0
| Command | Meaning |
|---|---|
&P0 | Make 39 percent, break 61 percent |
&P1 | Make 33 percent, break 67 percent |
Sets the serial port Data Set Ready (DSR) signal. Table 33 lists command options.
&S0
| Command | Meaning |
|---|---|
&S0 | DSR is always on. Equivalent to setting the Serial Port DSR/CTS command \D. |
&S1 | DSR is on with answer tone. Equivalent to setting the Serial Port DSR/CTS command \D3. |
Configures the modem to run a local or remote diagnostic test. Use the &T0 command to stop a running diagnostic test.Table 33 lists command options.
&T5
| Command | Meaning |
|---|---|
&T0 | |
&T1 | Runs a local analog loopback test. The modem should display characters on your screen exactly as you enter them. The modem must be in normal or direct mode and set to 1200 bps or higher. |
&T3 | Local digital loopback test. Allows a remote modem that does not support the CCITT V.54 standard to perform a remote digital loopback test with the modem. The modem must be in normal or direct mode and set to 1200 bps or higher. |
&T4 | Allows the modem to respond to a remote caller's request to enter remote digital loopback mode. The modem must be in normal or direct mode and set to 1200 bps or higher. |
&T5 | Prevents the modem from responding to a remote digital loopback request. |
&T6 | Instructs the remote modem to initiate a remote digital loopback test. The modem must be in normal or direct mode and set to 1200 bps or above. |
&T7 | Instructs the remote modem to enter a remote digital loopback with a self-test. After the test is complete, the remote modem reports errors to the local device. The modem must be in normal or direct mode and set to 1200 bps or above. |
&T8 | Runs a local analog loopback with a self-test. The modem sends itself the ITU-T V.54 test pattern, verifies characters to make sure they are received correctly, and reports errors to the local device. The modem must be in normal or direct mode and set to 1200 bps or above. |
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.
![]() |
Note The &W command does not save registers S2 to S12; the AT*W command saves all registers. |
![]() |
Note The &W and *W commands share the same stored configuration area. Either of these commands overrides the other's stored settings. *W also stores settings for restricted S registers S2 to S12. If &W is used after *W, the default settings for the restricted S registers are restored. The stored settings are not saved during power up. |
This section describes modem commands that begin with a right-parenthesis ()) character.
Adjusts power levels during link negotiation for reliable connections to accommodate signaling requirements of cellular telephone equipment. Table 34 lists command options.
)M0
| Command | Meaning |
|---|---|
)M0 | Adjusts the power level for central site modems if the remote modem is set to) M1. Use this option for MNP Class 10 modems that connect to both cellular and noncellular site modems. |
)M1 | Autoadjusts the power level for cellular modems. |
This section describes modem commands that begin with an asterisk (*) character.
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).
No default identifier.
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.
![]() |
Note The AT*W command saves all registers; the &W command does not save registers S2 to S12. |
![]() |
Note The &W and *W commands share the same stored configuration area. Use one of the commands to override the other stored settings. The &W command stores the default settings for the restricted S registers S2 to S12. If &W is used after a *W command, the default settings for the restricted S registers are stored. The stored settings are not saved during power up. |
This section describes modem commands that begin with a hyphen (-) character.
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 36 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.
| Command | Meaning |
|---|---|
-D/n | n is an integer between 1 and 9 that specifies a telephone number stored with the \P command. |
-DL | Redials the last number dialed. |
-DS | Dials the first entry stored in the directory. |
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 37 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.
-E0
| Command | Meaning |
|---|---|
-E0 | Enables 10-bit data during normal mode connections |
-E1 | Enables 11-bit data during normal mode connections |
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 38 lists command options.
-H0
| Command | Meaning |
|---|---|
-H0 | Smart mode |
-H1 | Dumb mode |
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 38 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:
![]() |
Note You can also set country codes using Cisco IOS commands for Releases 11.2(10)P and later as well as 11.3(2)T and later. For more information, see the description of the modem country command in New and Changed Cisco IOS Commands for the Cisco AS5300, which is available at www.cisco.com. |
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.
Follow these steps:
Router>enableRouter#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 38. In the following example, the country code is set to "18" for the Czech/Slovak Republic:
Router(config)#modemcap edit micro_czech miscellaneous-I18Z
| Country | Country Code | Country Code Displayed in Banner |
|---|---|---|
Australia | 20 | 49 |
Austria | 22 | 92 |
Belgium1 | 23 | 67 |
Czech/Slovak Republic1 | 18 | 91 |
Denmark | 10 | 63 |
Finland | 9 | 71 |
France1 | 25 | 32 |
Germany | 17 | 68 |
Israel | 15 | 16 |
Italy | 3 | 21 |
Ireland | 24 | 97 |
Japan | 13 | 14 |
Netherlands | 5 | 04 |
New Zealand | 11 | 55 |
Norway | 8 | 72 |
Poland | 19 | 93 |
Portugal | 27 | 94 |
Spain | 6 | 76 |
South Africa | 16 | 69 |
Sweden | 7 | 09 |
Switzerland1 | 14 | 66 |
UK2 | 2 | 12 |
USA3 | 1 | 85 |
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.
Router(config)#no modem fast-answerRouter(config)#modemcap edit micro_czech autoanswer s0=2
Router(config)#modemcap edit micro_czech miscellaneous :T26=8-I18ZRouter(config)#exit Router#
![]() |
Note Modem firmware Release 1.0.23 does not require the :T26=8 setting because it does not support digital fast-connect. |
Step 4 Enter global configuration mode and specify the lines on which to apply the new modemcap. Lines 1 through 48 are specified in the following example:
Router#config termRouter(config)#line 1 48Router(config-line)#modem autoconfigure typemicro_czech
Some messages display while the modems are reconfigured using the new modemcap. When the last message appears, press Return:
. . . 3w5d: TTY48: Done with modem configuration
Step 5 Save the configuration changes to NVRAM:
Router(config-line)# Ctrl-Z
Router# copy running-config startup-config
[OK]
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#
![]() |
Note The Miscellaneous (MSC) field is the only nondefault field set in the modemcap. |
The following example shows verification using 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.
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 40 lists command options.
-J1
| Command | Meaning |
|---|---|
-J0 | Disables detect phase |
-J1 | Enables detect phase |
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 41 lists command options.
-K1
| Command | Meaning |
|---|---|
-K0 | Disables MNP extended services |
-K1 | Enables MNP extended services |
-K2 | Enables MNP extended services without MNP indication during the answer detect phase |
Determines whether MNP class connect messages are displayed. Table 42 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:
CONNECT
-M0
| Command | Meaning |
|---|---|
-M0 | Disables MNP class connect messages |
-M1 | Enables the following formats for MNP class connect messages, where n equals MNP class (from 1 to 10), and x means the type of data compression (V.42 bis or MNP Class 5):
|
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 43 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.
-O4
| Command | Meaning |
|---|---|
-O0 | 7 data bits, odd parity |
-O1 | 7 data bits, even parity |
-O2 | 7 data bits, mark parity |
-O3 | 7 data bits, space parity |
-O4 | 8 data bits, no parity |
-O5 | 8 data bits, odd parity |
-O6 | 8 data bits, even parity |
-O7 | 8 data bits, mark 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 44 lists command options.
-P0
| Command | Meaning |
|---|---|
-P0 | Ignores parity for special characters. All received data is passed to the workstation with parity corrected to match the serial port parity. |
-P1 | Processes special characters received from the workstation only if their parity matches the serial port parity. All received data is passed to the workstation at 8 data bits with no parity. |
-P2 | Processes special characters only if their parity matches the serial port parity. Modem port flow control characters are recognized, regardless of whether their parity matches the serial port parity. All received data is passed to the workstation with parity corrected to match the serial port parity. |
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 45 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).
-Q2
| Command | Meaning |
|---|---|
-Q0 | Disables fallback from a V.32 bis or V.32 MNP reliable connection to an MNP reliable 2400 or 1200 bps connection |
-Q1 | Enables fallback from a V.32 bis or V.32 MNP reliable connection to an MNP reliable 2400 bps connection |
-Q2 | Enables fallback from a V.32 bis or V.32 MNP reliable connection to an MNP reliable 2400 or 1200 bps connection |
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). Table 46 lists split serial port speed command options.
-V1 for U.S.
-V0 for international
| Command | Meaning |
|---|---|
-V0 | Enables V.23 split modem port speed connections within the multiprotocol autoanswer feature |
-V1 | Disables V.23 split modem port speed connections within the multiprotocol autoanswer feature |
This section describes modem commands that begin with a colon (:) character.
Sets the modem off-hook in originate mode when DTR is raised. Table 47 lists command options.
:D0
| Command | Meaning |
|---|---|
:D0 | The modem is not set off-hook when DTR is raised. |
:D1 | The modem is set off-hook in originate mode when DTR is raised. &Dn (DTR Control) also must be set. For example, if &D2 is set, the modem is set off-hook 5 seconds after recognizing the positive transition of DTR. |
:D2 | The modem is set off-hook in originate mode and dials the first stored telephone number when DTR is raised. &Dn must also be set. |
Configures the modem to use the compromise equalizer when it connects in V.32 mode. Table 48 lists command options.
:E1
| Command | Meaning |
|---|---|
:E0 | Disables the compromise equalizer only when the modem is in V.32 mode. Use :E0 only when you are performing back-to-back or PBX-to-PBX V.32 mode connections. |
:E1 | Enables the compromise equalizer. Use :E1 for outside line-to-outside line or PBX-to-outside line connections. |
Displays the contents of :T register n (where n is a decimal number).
This section describes modem commands that begin with an at (@) character.
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 49 lists command options.
@C0
| Command | Meaning |
|---|---|
@C0 | Sets CTS, DSR, and DCD on before the connect message is sent |
@C1 | Sets CTS, DSR, and DCD on after the connect message is sent |
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,".
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 50 lists selected transmit level command options.
@M0
| Command | Meaning |
|---|---|
@M0 | -26 dBm |
@M1 | -30 dBm |
@M2 | -10 dBm |
@M10 | -10 dBm |
@M35 | -35 dBm |
The AT@U command sets the minimum connection speed for both Rx and Tx speeds. Use the AT@U command to execute the following connections:
This section describes modem commands that begin with a backslash (\) character.
Sets the maximum block size for MNP stream link connections. Table 51 lists command options.
\A3
| Command | Meaning |
|---|---|
\A0 | 64 characters |
\A1 | 128 characters |
\A2 | 192 characters |
\A3 | 256 characters |
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).
1 to 9 (100-millisecond increments)
\B3 (300 milliseconds)
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 52 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).
\C0
![]() |
Note When either \C1 or \C2 is set, reliable and normal connections can result regardless of bps rate adjustments. |
| Command | Meaning |
|---|---|
\C0 | Data is not buffered during link negotiation. The modem changes to normal or direct mode if a SYN character is not detected within 3 seconds. |
\C1 | Buffers all data on the answering modem until 200 non-SYN characters are received or a SYN character is detected within 3 seconds. If 200 non-SYN characters are received, the modem changes to normal mode and passes the data to the serial port. If the modem detects a SYN character within 3 seconds, it attempts to establish a reliable connection. Otherwise, the modem changes to normal mode. |
\C2 | Data is not buffered on the answering modem. The modem changes to normal mode when it receives an autoreliable fallback character defined by the %A command and passes that character to the serial port. Use the%C2 command when the modem receives calls from both modems that support MNP and modems that do not support MNP, so that the modem can change to normal mode as soon as it detects a logon character (defined by %A) from a non-MNP caller, eliminating the 3-second wait. |
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 53 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.
\D0
| Command | Meaning |
|---|---|
\D0 | DSR and CTS are always on. |
\D1 | DSR and CTS follow DCD. If the &C1 command (Serial Port DCD Control) is also set, DSR follows off-hook. |
\D2 | DSR and CTS both follow DCD. |
\D3 | DSR follows the answer tone, CTS is always on. |
\D41 | CTS is help low during modem training after DCD is asserted. |
| 1Version 3.2.10 supports PoS functionality. &C3 will never be used without \D4 (see "). For more information, see "PoS Support,". |
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 54 lists command options and signal level results.
| &Cn Option | \Dn Option | Result |
|---|---|---|
0 | 0 | DCD on, DSR on, CTS on |
0 | 1 | DCD on, DSR on, CTS on |
0 | 2 | DCD on, DSR on, CTS on |
0 | 3 | DCD on, DSR with answer tone, CTS on |
0 | 4 | DCD on, CTS and DTR comply with ITU-T recommendations |
1 | 0 | DCD follows modem carrier, DSR on, CTS on |
1 | 1 | DCD follows modem carrier, DSR follows off-hook, CTS follows CD |
1 | 2 | DCD follows modem carrier, DSR and CTS both follow CD setting |
1 | 3 | DCD follows modem carrier, DSR with the answer tone, CTS on |
1 | 4 | DCD follows modem carrier, CTS and DTR comply with ITU-T recommendations |
2 | 0 | DCD on (off for a few seconds at disconnect only), DSR on, CTS on |
2 | 1 | DCD, DSR, and CTS on (off for a few seconds at disconnect) |
2 | 2 | DCD, DSR, and CTS on (off for a few seconds at disconnect) |
2 | 3 | DCD off at disconnect then on, DSR with the answer tone, CTS on |
2 | 4 | DCD on (off for a few seconds at disconnect only), CTS and DTR comply with ITU-T recommendations |
Configures the modem to echo characters sent from the local workstation in connect state. Table 55 lists command options.
\E0
| Command | Meaning |
|---|---|
\E0 | Does not echo data sent by the local workstation. |
\E1 | Echoes data sent by the local workstation. \E1 functions only with normal mode connections. |
Displays the telephone numbers currently stored in the telephone directory.
Sets the flow control method used to pace data between modems during a normal mode connection. Table 56 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.
\G0
| Command | Meaning |
|---|---|
\G0 | Disables modem port flow control. |
\G1 | Sets modem port flow control to XON/XOFF. The modem sends an XOFF character to stop received data and sends an XON character to resume reception of data. |
\G2 | Sets modem port flow control to unidirectional XON/XOFF. The modem sends XON and XOFF characters to the remote device but ignores XON and XOFF received from the remote device. |
Automatically adjusts the speed of the serial port to match the speed of the connection. Table 57 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.
\J0
![]() |
Note When \J1, \C0 (the autoreliable buffer), and \N3 (the autoreliable mode) are set, the modem uses direct mode instead of normal mode if a reliable connection is not established. |
| Command | Meaning |
|---|---|
\J0 | Disables bps rate adjust. The serial port rate is independent of the rate of the connection. This option is recommended for the highest throughput when data compression is used. |
\J1 | Enables bps rate adjust. The modem automatically adjusts the speed of the serial port to match the speed of the connection until the connection terminates. If your workstation does not automatically change to the adjusted bps rate, you must manually change the bps rate to the new setting. See the %U command (Clear Serial Port Speed) for information about resetting the serial port bps rate. |
Determines the type of Break the modem transmits when it receives a Break. Table 58 describes the effect of n. The modem can buffer up to four Breaks on both the modem port and the serial port.
\K5
![]() |
Note In reliable link connect state, the sender's Break control setting determines how the receiver handles the Break. |
| Command | Local DTE Sends Break During Reliable or Normal Connection | Local DTE Sends \Bn, Local Modem in Command Mode, During Reliable or Normal Connection | Local Modem Sends Break During Direct Connection | Remote Modem Sends Break During Normal Connection |
|---|---|---|---|---|
\K0 | Enter command state; no Break to the remote system1 | Empty data buffers; send a Break to the remote system | Send a Break to the remote system; set the modem to command state | Empty data buffers; send a Break to the serial port |
\K1 | Empty data buffers; send a Break to the remote system | Same as \K0 | Send a Break to the remote system | Same as \K0 |
\K2 | Same as \K0 | Immediately send a Break to the remote system | Same as \K0 | Immediately send a Break to the serial port |
\K3 | Immediately send a Break to the remote system | Same as \K2 | Same as \K1 | Same as \K2 |
\K4 | Same as \K0 | Send a Break to the remote system in sequence with any transmit data being buffered | Same as \K0 | Send a Break to the serial port in sequence with the receive data being buffered |
\K5 | Send a Break to the remote system in sequence with transmit data | Same as \K4 | Same as \K1 | Same as \K4 |
| 1Forces the modem to command state. To transmit a Break and enter connect state, enter the \B0 command. See the \B command description for details.) |
Selects the modem operating mode. Table 59 lists command options.
\N3
![]() |
Note You can set the operating mode for a single call using dial modifiers. See Table 3 for details. |
| Command | Meaning |
|---|---|
\N0 | Sets normal mode. \N0 can be used to communicate with most modems. No error correction is performed in normal mode. |
\N1 | Sets direct mode. \N1 ignores flow control and does not buffer data. In connect state, the serial port always adjusts to the speed of the connection for any \Jn setting. No error correction is performed in direct mode. The escape code sequence is disabled in direct mode if \J0 is set. |
\N2 | Sets MNP reliable mode to provide error detection and automatic data retransmission between systems that support the MNP reliable link. The modem disconnects if it fails to establish an MNP reliable link immediately after making a connection. Some protocols are not timed to work with MNP and can interfere with its effectiveness. Both modems should use flow control on the serial port in an MNP reliable link. When a transmission error is detected, data is buffered during the retransmission. |
\N3 | Sets autoreliable mode. The answering modem looks for incoming MNP or LAPM protocol characters from the remote modem. If it detects the characters within approximately 3 seconds, it tries to establish a reliable link connection. If both modems are set to autoreliable mode, a normal connection or no connection can result because of noise on the telephone line. When the modem is set to autoanswer in autoreliable mode, you can shorten the 3-second period by using the %A command with the \C2 command. \N3 lets the modem communicate with remote modems that may not support the MNP or LAPM reliable link. |
\N4 | Sets LAPM reliable mode to provide error detection and automatic data retransmission between systems that support the LAPM reliable link. The modem disconnects if it fails to establish a LAPM reliable link immediately after making a connection. |
\N5 | |
\N6 |
Table 60 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.
![]() |
Note For LAPM connections listed in Table 59, if the originate and answer modems have -K1 (MNP Extended Services) set for V.42 connections, the extended features of MNP are applied during the connection. |
| Answering Modem | Originating Modem | ||||||
|---|---|---|---|---|---|---|---|
\N0 | \N1 | \N2 | \N3 | \N4 | \N5 | \N6 | |
\N0 | Normal | Direct/normal | NC | Normal | NC | Normal | NC |
\N1 | Normal/direct | Direct | NC | Normal/direct | NC | Normal/direct | NC |
\N2 | NC | NC | MNP | MNP | NC | NC | MNP |
\N3 | Normal | Direct/normal | MNP | MNP | LAPM | LAPM | LAPM |
\N4 | NC | NC | NC | LAPM | LAPM | LAPM | LAPM |
\N5 | Normal | Direct/normal | NC | LAPM1 | LAPM | LAPM | LAPM |
\N6 | NC | NC | MNP | MNP | LAPM | LAPM | LAPM |
| 1For the modem to establish a LAPM connection, -K0 must be set. |
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.
Selects the flow control method used in the serial port. In direct mode connections, the modem ignores the \ Qn command. Table 61 lists command options.
\ Q3
| Command | Meaning |
|---|---|
\ Q0 | Disables flow control. |
Enables bidirectional XON/XOFF flow control. Data transmission is stopped by an XOFF character and restarted by an XON character. The modem generates XON and XOFF characters at the same parity used on the serial port. The serial port responds to XON and XOFF characters sent by the local workstation in the same way. | |
Enables unidirectional CTS/RTS hardware flow control. The modem turns CTS off to signal the local workstation to stop transmitting data and turns CTS on to signal the local workstation to resume transmitting data. | |
Enables bidirectional CTS/RTS hardware flow control. The modem uses CTS to start and stop transmission from the local workstation. When RTS is off, the modem stops transmitting. When RTS is on the modem resumes transmission. | |
Enables unidirectional XON/XOFF flow control. The modem serial port generates, but does not respond to, XON/XOFF flow control characters. This setting allows for computers to transmit data that contains XON and XOFF data characters. The computer can still be set to respond to XON/XOFF flow control characters sent to it from the modem during serial port flow control. | |
\ Q5 | Enables unidirectional hardware flow control and keeps CTS off until the connection is established. |
\ Q6 | Enables bidirectional hardware flow control and keeps CTS off until a connection is established. RTS is ignored when it is not connected. |
Controls the Ring Indicator (RI) signal. RI follows the incoming ring signal on the telephone line. Table 62 lists command options.
\R1
| Command | Meaning |
|---|---|
\R0 | Turns on the ring indicator signal after the ring and keeps it on for the duration of the telephone call. |
\R1 | Turns off the ring indicator signal after the telephone call is answered. |
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.
![]() |
Note Some commands listed in the output do not apply to your modems, for example SPKR CTRL and SPKR VOL are not supported in any universal access server 12-port modem module. |
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
![]() |
Note On V.34 or 56K modems, the 00B MABP port address is a variable from 1-24. |
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.
0 to 90 minutes
\T0 (disabled)
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 63 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.
\V2
| Command | Meaning |
|---|---|
\V0 | Displays standard long form result codes, CONNECT speed. Use \V0 when your communications software does not expect a reliable link result code, even if a reliable connection is established. |
\V1 | Adds /REL to long form error correction result codes, CONNECT speed /REL. 9600/REL also indicates 4800-, 7200-, and 12000-bps reliable connections. |
\V2 | Displays long form error correction protocol result codes:
9600/REL also indicates 4800-, 7200-, and 12000-bps reliable connections. |
\V3 | Adds /REL to long form error correction result codes, CONNECT speed /REL Displays Hayes-compatible short form result codes. The result code displays the actual modem bps rate. |
\V4 | Enables long form error correction result codes:
The result code displays the actual modem bps rate. |
\V5 | Enables reporting of the modulation type:
|
The Cisco AS5300 access server module can also display these result codes when it attempts to establish connection. The tables use the abbreviations: rel (reliable) and non-rel (non reliable).
The following tables (Table 64 through Table 67) show the short and long form result codes, excluding connection result codes whose form depends on the \V, W, and -M commands.
| Short Form | Long Form |
|---|---|
0 | OK |
1 | CONNECT |
2 | RING |
3 | NO CARRIER |
4 | ERROR |
6 1 | NO DIALTONE |
| 1display of these call progress monitoring result codes depends on the setting of the X command. |
| ATV1 - M0W0 or ATV1 M0W1 Report DTE speed | ||
|---|---|---|
| DTE Speed | non-rel \V rel | \V1 rel, \V rel1 \V3 rel, \V4 rel1, \V5 rel2 |
75 | 75 | 75 /REL |
300 | 300 | 300 /REL |
600 | 600 | 300 /REL |
1200 | 1200 | 1200 /REL |
2400 | 2400 | 2400 /REL |
4800 | 4800 | 4800 /REL |
9600 | 9600 | 9600 /REL |
19,200 | 19200 | 19200 /REL |
38,400 | 38400 | 38400 /REL |
57,600 | 57600 | 57600 /REL |
115,200 | 115200 | 115200 /REL |
230,400 | 230400 | 230400 /REL |
| 1If \V2 or \V4 are set and a reliable link is established, the message displays as one of the following formats: CONNECT <speed>/REL - MNP or CONNECT <speed>/REL - LAPM or CONNECT <speed>/REL - CELLULAR or CONNECT <speed>/REL- CELLULAR EC or CONNECT <speed> /LAPM - CELLULAR EC 2In non-reliable V.21 or Bell 103 connections, the message displays as CONNECT. |
| ATV1-M0W2 Report modulation speed |
| |||
Modulation | Speed | non-rel \V0 rel | \V1 rel \V2 rel1 | \V3 rel \V4 rel1 \V5 rel2 |
V.21 | 300 | V.21/REL | V.21/REL | |
Bell 103 | 300 | --- 3 | 103/REL | 103/REL |
V.23 half-duplex | 1200 | V.23 HDX4 | --- | --- |
V.23 split speed | 75/1200 | V.234 | --- | --- |
V.22 | 6004 | 600 | 600/REL | 600/REL |
V.22 \Bell 212A | 1200 | 1200 | 1200/REL | 1200/REL |
V.34/V.22bis | 2400 | 2400 | 2400/REL | 2400/REL |
V.34/V.32 | 4800 | 4800 | 9600/REL | 4800/REL |
V.34/V.32bis | 7200 | 7200 | 9600/REL | 7200/REL |
V.34/V.32 | 9600 | 9600 | 9600/REL | 9600/REL |
V.34/V.32bis | 12000 | 12000 | 9600/REL | 12000/REL |
V.34/V.FC/V.32bis | 14400 | 14400 | 14400/REL | 14400/REL |
V.34/V.FC | 16800 | 16800 | 16800/REL | 16800/REL |
V.34/V.FC | 19200 | 19200 | 19200/REL | 19200/REL |
V.34/V.FC | 21600 | 21600 | 21600/REL | 21600/REL |
V.34/V.FC | 24000 | 24000 | 24000/REL | 24000/REL |
V.34/V.FC | 26400 | 26400 | 26400/REL | 26400/REL |
V.34/V.FC | 28800 | 28800 | 28800/REL | 28800/REL |
V.34 | 31200 | 31200 | 31200/REL | 31200/REL |
V.34 | 33600 | 33600 | 33600/REL | 33600/REL |
K56flex | 32000 | 32000 | 32000/REL | 32000/REL |
K56flex | 34000 | 34000 | 34000/REL | 34000/REL |
K56flex | 36000 | 36000 | 36000/REL | 36000/REL |
K56flex | 38000 | 38000 | 38000/REL | 38000/REL |
K56flex | 40000 | 40000 | 40000/REL | 40000/REL |
K56flex | 42000 | 42000 | 42000/REL | 42000/REL |
K56flex | 44000 | 44000 | 44000/REL | 44000/REL |
K56flex | 46000 | 46000 | 46000/REL | 46000/REL |
K56flex | 48000 | 48000 | 48000/REL | 48000/REL |
K56flex | 50000 | 50000 | 50000/REL | 50000/REL |
K56flex | 52000 | 52000 | 52000/REL | 52000/REL |
K56flex | 54000 | 54000 | 54000/REL | 54000/REL |
K56flex | 56000 | 56000 | 56000/REL | 56000/REL |
| 1If \V2 or \V4 are set and a reliable link is established, the message displays as one of the following formats: CONNECT <speed>/REL - MNP or CONNECT <speed>/REL - LAPM or CONNECT <speed>/REL - CELLULAR or CONNECT <speed>/REL- CELLULAR EC or CONNECT <speed> /LAPM - CELLULAR EC 2If \V5 is set, the message displays in one of the following formats: CONNECT <DCE speed>/<modulation>/REL-CELLULAR CONNECT <DCE speed>/<modulation>/REL-LAPM CONNECT <DCE speed>/<modulation>/REL-MNP CONNECT <DCE speed>/<modulation>/REL-CELLULAR EC CONNECT <DCE speed>/<modulation>/REL-LAPM - CELULAR EC with the modulation /V.FC, /K56, /V.34, /V.32, /V.22, or /FSK 3In a non-reliable V.21 or Bell 103 connections, the message displays as CONNECT. 4Not supported in synchronous mode. |
| ATV0W0 or ATV0W1 Report DTE speed | |||
DTE Speed | \V0 \V1 non-rel \V2 non-rel \V4 non-rel \V5 non-rel | \V1 rel \V2 rel \V4 rel \V5 rel | \V3 |
75 | 1 | 20 | 1 |
300 | 1 | 20 | 1 |
600 | 9 | 21 | 5 |
1200 | 5 | 22 | 5 |
2400 | 10 | 23 | 10 |
4800 | 30 | 31 | 11 |
9600 | 32 | 33 | 12 |
19200 | 36 | 37 | 14 |
38400 | 38 | 39 | 28 |
57600 | 42 | 43 | 29 |
115200 | 46 | 47 | 30 |
230400 | 48 | 49 | 51 |
| ATV0W2 Report Modulation Speed | ||||||
Modulation | Speed | \V0 \V1 non-rel \V2 non-rel \V4 non-rel \V5 non-rel | \V1 rel \V2 rel | \V3 | \V4 rel \V5 rel | Non-compression |
V.21 or Bell 103 | 300 | 1 | 20 | 1 | 20 | 79 |
V.23 half-duplex | 1200 | 5 |
| 5 |
| 24 |
V.23 split speed | 75/1200 | 11 |
| 23 |
| 24 |
V.22 | 600 | 9 | 21 | 5 | 21 | 21 |
V.22 or Bell 212A | 1200 | 5 | 22 | 5 | 22 | 80 |
V.34/V.22bis | 2400 | 10 | 23 | 10 | 23 | 81 |
V.34/V.32 | 4800 | 30 | 31 | 11 | 31 | 82 |
V.34/V.32bis | 7200 | 401 | 33 | 24 | 41 | 83 |
V.34/V.32 | 9600 | 32 | 33 | 12 | 33 | 84 |
V.34/V.32bis | 12000 | 441 | 33 | 25 | 45 | 85 |
V.34/V.FC/V.32bis | 14400 | 341 | 35 | 13 | 35 | 87 |
V.34/V.FC | 16800 | 60 | 61 | 13 | 61 | 88 |
V.34/V.FC | 19200 | 36 | 37 | 14 | 37 | 89 |
V.34/V.FC | 21600 | 62 | 63 | 13 | 63 | 90 |
V.34/V.FC | 24000 | 64 | 65 | 13 | 65 | 91 |
V.34/V.FC | 26400 | 66 | 67 | 13 | 67 | 92 |
V.34/V.FC | 28800 | 68 | 69 | 13 | 69 | 93 |
V.34 | 31200 | 70 | 71 | 13 | 94 | 94 |
V.34 | 33600 | 72 | 73 | 13 | 95 | 95 |
K56flex | 32000 | 130 | 131 | 15 | 131 | 160 |
K56flex | 34000 | 132 | 133 | 15 | 133 | 161 |
K56flex | 36000 | 134 | 135 | 15 | 135 | 162 |
K56flex | 38000 | 136 | 137 | 15 | 137 | 163 |
K56flex | 40000 | 138 | 139 | 15 | 139 | 164 |
K56flex | 42000 | 140 | 141 | 15 | 141 | 165 |
K56flex | 44000 | 142 | 143 | 15 | 143 | 166 |
K56flex | 46000 | 144 | 145 | 15 | 145 | 167 |
K56flex | 48000 | 146 | 147 | 15 | 147 | 168 |
K56flex | 50000 | 148 | 149 | 15 | 149 | 169 |
K56flex | 52000 | 150 | 151 | 15 | 151 | 170 |
K56flex | 54000 | 152 | 153 | 15 | 153 | 171 |
K56flex | 56000 | 154 | 155 | 15 | 155 | 172 |
| 1When \V0 is set, the following numeric codes display: 14400 bps=34; 12000 bps=44; 7200 bps=40. |
Determines whether the serial port uses split transmit and receive speed operation when %F1 or %F2 is set to select V.23 mode. Table 69 lists command options.
\W0
| Command | Meaning |
|---|---|
\W0 | Disables split serial port speed |
\W1 | Enables split serial port speed |
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 70 lists command options.
\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. |
| Command | Meaning |
|---|---|
\X0 | Processes XON/XOFF flow control characters |
\X1 | Processes XON/XOFF flow control characters and passes them to the local or remote system |
This section describes modem command that begins with a # character. Table 71 lists # command options.
#E1
| Command | Meaning |
|---|---|
#E0 | Enables the escape code sequence in answer mode. |
#E1 | Disables the escape code sequence in answer mode. |
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.
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.
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.
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.
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.
The AT? command displays the value of the last S register referenced in a read, write, or pointer command.
The AT=x command changes the value of the last S register referenced to x.
This section describes the purpose and format of each S register.
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.
0 to 255 rings
1 ring
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.
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.
0 to 255 (ASCII decimal)
43 (+)
Specifies the carriage return (CR) character. The carriage return terminates command lines and result codes.
0 to 127 (ASCII decimal)
13 (Carriage Return)
Specifies the linefeed (LF) character. The linefeed character follows a carriage return at the end of command lines and result codes.
0 to 127 (ASCII decimal)
10 (Linefeed)
Specifies the backspace (BS) character.
0 to 32 (ASCII decimal)
8 (Backspace)
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.
2 to 255 seconds
2 seconds
Specifies the time that the modem waits for one of the following:
0 to 255 seconds
60 seconds
Specifies the time the modem waits when the pause dial modifier (,) is used in a dial string.
0 to 255 seconds
0
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.
0 to 255 (0.1-second increments)
6 (0.6 seconds)
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.
![]() |
Note Register S10 is ignored in 56 kbps, V.34, V.32, V.32 bis, V.22, and V.22 bis reliable connections. |
0 to 255 (0.1-second increments)
60 (6 seconds)
Specifies the time interval in milliseconds between tones when the modem is dialing over a tone line.
50 to 100 milliseconds
50 milliseconds
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.
0 to 255 (0.02-second increments)
50 (1 second)
Register S14 is bit-mapped for the functions listed in Table 72.
| Bit | Meaning | Value |
|---|---|---|
0 | Not used | - |
1 | Command echo | 0 No echo |
2 | Result codes | 0 Result codes |
3 | Result type | 0 Short form |
4 | Dumb mode | 0 Smart mode |
5 | Dial method | 0 Tone dial |
6 | Not used | - |
7 | Originate/answer | 0 Answer mode |
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 73.
| Bit | Meaning | Value |
|---|---|---|
0 | Local analog loopback | 0 Disabled |
1 | Not used | - |
2 | Local digital loopback | 0 Disabled |
3 | Remote digital loopback status | 0 Loopback off |
4 | Initiate remote digital loopback | 0 Disabled |
5 | Initiate remote digital loopback with self-test | 0 Disabled |
6 | Initiate local analog loopback with self-test | 0 Disabled |
7 | Not used | - |
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.
0 to 255 seconds
0 (disables the timer)
Register S21 is bit-mapped for the functions listed in Table 74.
| Bit | Meaning | Decimal Value |
|---|---|---|
0 | Telco jack | 0 Default. 1 Not supported. |
1 | Not used | - |
2 | Clear To Send/ | 0 On-hook: CTS on. Off-hook: V.22 and V.22 bis CTS off until connecting. After connecting: CTS is off in response to an on-to-off RTS transition; CTS is on in response to an off-to-on RTS transition after the delay time set in register S26. 1 On-hook: CTS on. Off-hook: CTS off until connecting. After connecting: CTS on for duration of carrier signal. |
3, 4 | Data Terminal Ready | 0 Ignores DTR. 1 On-to-off DTR transition: modem enters command state. 2 On-to-off DTR transition: modem is set on-hook. 3 On-to-off DTR transition: modem reset. |
5 | Data Carrier Detect | 0 DCD always on. 1 DCD on indicates data carrier is present except momentarily at disconnect. |
6 | Not used | - |
7 | Long space disconnect | 0 Disabled. 1 Enabled. |
Register S22 is bit-mapped for the functions listed in Table 75.
| Bit | Meaning | Decimal Value |
|---|---|---|
0-3 | Not used | - |
4, 5, 6 | Result code options | 0 Same as X0 4 Same as X1 5 Same as X2 6 Same as X3 7 Same as X4 |
7 | Make/break ratio | 0 Make 39 percent, break 61 percent 1 Make 33 percent, break 67 percent |
Register S23 is bit-mapped for the functions listed in Table 76.
| Bit | Meaning | Decimal Value |
|---|---|---|
0 | Respond to remote digital loopback (ignored in reliable connections) | 0 Disabled 1 Enabled |
1, 2, 3 | Serial port bps rate | 0 0 to 300 bps 1 600 bps 2 1200 bps 3 2400 bps 4 4800 bps 5 9600 bps 6 19200 bps 7 38400, 57600, or 115200 bps |
4, 5 | Parity | 0 Even 1 Space/none 2 Odd 3 Mark |
6, 7 | Guard tone | 0 Disabled 1 550 Hz 2 1800 Hz 3 Not used |
The modem ignores an on-to-off transition of DTR that is less than the register S25 time delay.
0 to 255 (0.01-second increments for Delay to DTR, 1 second for asynchronous mode)
5 (0.05 seconds for Delay to DTR, 5 seconds for asynchronous mode)
Register S27 is bit-mapped for the functions listed in Table 77.
| Bit | Meaning | Decimal Value |
|---|---|---|
0, 1 | Not supported | - |
2, 3, 4, 5 | Not used | - |
6 | Answer tone at 1200 bps | 0 CCITT V.22 bis/V.22 1 Bell 212A |
7 | Not used | - |
This section describes the purpose and format of each supported :T register.
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.
0 to 255 (0.1-second increments)
40 (4 seconds)
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.
0 to 33 (0.1-second increments)
33 (3.3 seconds)
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.
0 to 255 (12.5-millisecond increments)
20 (250 milliseconds)
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.
0 to 255 milliseconds
200 milliseconds
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.
0 to 255 (decimal value of an 8-bit ASCII character)
17 (DC1 or 11 hexadecimal)
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.
0 to 255 (decimal value of an 8-bit ASCII character)
19 (DC3 or 13 hexadecimal)
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.
0 to 255 (decimal value of an 8-bit ASCII character)
249 (F9 hexadecimal)
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.
0 to 255 (decimal value of an 8-bit ASCII character)
251 (FB hexadecimal)
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).
0 to 255 (100-millisecond increments)
0
Register :T16 specifies the time that the modem waits before raising CTS after DCD or DSR has been raised in connect mode.
0 to 255 (12.5-millisecond increments)
0
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.
0, 1, or 5 to 32 seconds
0 (use dynamic training sequences, equivalent to a setting of 28)
Register :T19 specifies the MNP link control. The register is bit-mapped for the functions listed in Table 78.
| Bit | Meaning |
|---|---|
0 | 0 Keeps a non-MNP10 1200-bps connection if no MNP link activity is received from the remote modem 1 Disconnects a non-MNP10 1200-bps connection if no MNP link activity is received from the remote modem after 2 minutes |
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.
0 to 255 (12.5-millisecond increments)
34 (425 milliseconds)
Register :T23 is bit-mapped for the functions listed in Table 79.
| Bit | Meaning | Value |
|---|---|---|
0, 1, 2, 3 | Not used | - |
4 | Rate negotiation at startup | 1 At the start of a V.32 connection, modem examines line quality and sets speed accordingly 2 Disabled |
5, 6, 7 | Not used | - |
Register :T26 is bit-mapped for the functions listed in Table 80.
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).
| Bit | Meaning |
|---|---|
0 | 0 Enables 2-second billing delay. 1 Disables 2-second billing delay. This setting decreases connection time but can affect establishing connections. |
1 | 0 Enables normal answer tone length in V.32 mode. 1 Shortens answer tone length in V.32 mode. |
3 | 0 DisablesQuick Ring detection. 1 Enables Quick Ring detection. |
Register :T51 defaults to 13 and effects V.34 connections. This register was formerly reserved for Lease Line Mode Tx levels, unused in Cisco implementation.
Register :T52 has been revised to support independent V.90 Tx Power Level Adjust in firmware version 5.3.30. :T52 has been modified for the transmit power level for V.PCM (V.90) links. Default is -12 dBm for V.90 (the same as K56Plus, K56Flex 1.0, and K56Flex 1.1). The transmit level for V.90 modulation may be adjusted up or down with this register. Cisco recommends that it should be used at the default value unless performing specific fault isolation testing.
Register :T89 was implemented with version 3.2.10 and has been revised for firmware version 5.3.30. :T89 works in conjunction with and . For more information, see "PoS Support,"). Table 81 lists register :T89 configurations.
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.
Set :T89 = 6 for standard PoS devices. For specialized PoS devices using 1650Hz to Quick Connect, set :T89 = 22 (bits 1+2+4 set).
![]() |
Note Do not set bit position 3 unless testing in V.21 Leased Mode specifically. |
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). Use the following:
![]() |
Note If you are running firmware version 5.x.xx, and you want to configure POS, set :t110 = 46. |
0010 (0x2).
| Bit | Description | Meaning |
|---|---|---|
0 | ITU or Bell Mode | 0 ITU (See B0) 1 Bell (See B1) |
1 | 300/1200 Normal | 0 Attempt EC 1 Normal Mode, No EC |
2 | S-Reg 9 DCD Recognition Delay | 0 Use S9 1 Ignore S9 |
3 | Constant 1650 Hz Tone | 0 2100 Hz ABT 1 Constant 1650 Hz |
4 | Initial 1650 Hz Tone | 0 2100 Hz ABT 1 Timed 1650 Hz |
Register :T110 has been revised to default 0d36 matching server-client reported rates over Robbed bit signaling (RBS) in firmware version 5.0.xx.
:t110 = 4 (V.8bis enable, K56Flex. Default for version 3.2.10)
:t110 = 6 (V.8 enable, K56Flex. Default for version 3.1.30)
:t110 = 44 (K56Flex/V.90. Default for version 5.0.20 and later)
![]() |
Note If you are running Firmware release 5.0.xx, and you want to disable both Rockwell K56 implementations (K56Flex and K56Plus), set :T110 to 38 decimal and :T124 to 11 decimal. |
Register :T114 is used by 56-kbps modems to control/configure the modem for CT1 or PRI operation as listed in Table 82.
1
| Bit | Meaning |
|---|---|
0 | 0 Disable K56Flex 1 Enable K56Flex |
1 | 0 Normal Power (-12 dB) 1 High Power in A-Law (-6dB) |
Register :T120 is implemented with version 3.2.10. This register works in conjunction with . For more information, see "PoS Support,".
The default 0x19 = 0d25 for 2500 msec of 1650Hz tone by default. The project requirement is for this to be configurable for a range between 1500 msec and 3000 msec (1.5 sec. to 3.0 sec.). The actual range for the register is from 0 to 3100 msec (0 to 3.1 sec.) with the default being 2.5 seconds, which is deployed in the field at this time. When setting bit 4 of :T89, the value of :T120 is used for the duration of the tone.
11001 (0x19, 25 decimal) for 2500 milliseconds of 1650 Hz tone. See Table 83.
| Bit | Meaning |
|---|---|
0 | 1 |
1 | 0 |
2 | 0 |
3 | 1 |
4 | 1 |
Register :T121 is implemented with version 3.2.10. This register works in conjunction with . For more information, see "PoS Support,". Table 84 lists :T121 answerback tone configurations.
The default 0x1B = 0d27 for 2700 msec Answerback Tones by default. The project requirement is for this to be configurable for a range between 2500 msec and 3600 msec (2.5 sec. to 3.6 sec.). The actual range for the register is from 100 to 25500 msec (.1 to 25.5 sec.) with the default being 2.7 seconds, which is deployed in the field at this time.
11011 (0x1B, 27 decimal) 2700 milliseconds answerback tones.
| Bit | Meaning |
|---|---|
0 | 1 |
1 | 1 |
2 | 0 |
3 | 1 |
4 | 1 |
Register :T124 is implemented with version 5.0.xx. Setting this register to 11 decimal disables K56Plus. Table 85 lists :T124 configurations.
![]() |
Note To fully disable both Rockwell K56 implementations (K56Flex and K56Plus), set :T110 = 38 and :T124 = 11. |
43 (Decimal)
Bit | Meaning |
|---|---|
0 | 0 Disable V.90 1 Enable V.90 |
1 | (must be 1) |
2 | (must be 0) |
3 | (must be 1) |
4 | (must be 0) |
5 | 0 Disable K56Plus 1 Enable K56Plus (V.8 use PN + ID) |
Register :T127 supports server Rx aggression/nonaggression rate control in firmware version 5.3.30. This register may be used to eliminate cases of speed throttling or excessive V.42 receive errors on marginal circuits. Table 86 lists new bits for register :T127.
Register :T127 has 3 new bits defined (the default is still 0). Bits 2 and 3 are used to reduce the receive speeds for V.90, Flex and V.34 modulations. This is one of the enhanced Cisco Access Server features incorporated under CSCdk89980. Bit 4 is used to disable Digital Pad compensation. Set bit 4 = 1 to disable (CSCdk90934).
A workaround has been added to resolve an issue regarding Lucent-based V.90 clients making excessive (could be as high as 50% depending on client and firmware revision) normal mode connections when the client is set to defaults (S109=1). This client default will negotiate a V.90 or K56flex connection and allow the V.8bis handshake. V.90 was being advertised by the server modem by bit 1 in octet 15 of V.8bis (octet 15 sent as 83). The workaround is to clear this bit (octet 15 sent as 81) which will force a K56flex connection for Lucent clients ONLY. The current K56flex implementation does not have an issue of connecting in Normal mode, therefore connections will be more stable.
Bit 1 of :T127 controls the workaround. The default is zero (:T127=0). To disable the workaround, set :T127=2 (set bit 1).
| Bit 3 | Bit 2 | Meaning |
|---|---|---|
0 | 0 | Do not reduce speed (default) |
0 | 1 | Reduce speed by 1 rate (2400 bps) |
1 | 0 | Reduce speed by 2 rates (4800 bps) |
1 | 0 | Reduce speed by 3 rates (7200 bps) |
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 86. 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 87 provides a description of components of the report. Note that the table does not include self-explanatory fields.
| Field | Description |
|---|---|
Firmware Rev | Current firmware version |
Bootstrap Rev | Current Boot version |
DSP C36 Part/Rev | Current DSP version |
DSP Controller Rev1 | Current DSP hardware |
DSP Data Pump Rev1 | Current DSP controller pump |
Mod Type | Modulation type---specifies which modulation standard is being implemented on the current connection. If no connection is established, it will read IDLE. |
TX/RX Spd | TX/RX Speed---specifies the transmitter and receiver modulation speeds for the current connection. The TX/RX speeds may be different for operating modes that support split-speed operation, such as V.34. Given in bits per second. |
TX/RX Spd Mask | TX/RX speed mask---a hex number that shows which speeds the Rockwell DSP is configured to support on a given connection. For V.34, the LSB represents 2400 bps (1=on, 0=off); the next significant bit represents 4800 and so on up to 33.6 kbps. |
Symbol Rate | TX/RX symbol rate---a hex number that shows which symbol rate (analog signal event rate) the Rockwell DSP is currently using. For most modes, this will be a fixed number, but V.34 for example will negotiate any of 6 different rates from 2400 to 3429 symbols/second. |
TX/RX Carrier Freq | TX/RX carrier frequency---a single-frequency sinusoid that is modulated to transmit binary information in accordance with the selected operating modes. This also will usually be a fixed number except for V.34 where 9 different ones can be chosen. In the V.34 case, a low and a high carrier are available for each of the symbol rates. The appropriate symbol rate and its associated carrier will be selected by the modem during the startup sequence. Given in Hertz. |
TX/RX States TX/RX Trellis Code States | TX/RX Trellis states---Trellis Encoding is a method for improving noise immunity using a convolutional coder to select a sequence of subsets in a partitioned signal constellation. The trellis encoders used in the V.34 Recommendation are used in a feedback structure where the inputs to the trellis encoder are derived from the signal points. For V.34, this parameter tells whether 16, 32, or 64 state encoding is being used. |
TX/RX Nonliner Encoding TX/RX NLE | TX/RX nonlinear encoding---a method for improving distortion immunity near the perimeter of a signal constellation by introducing a non-uniform two-dimensional (2D) signal point spacing. |
TX/RX Precoding | TX/RX precoding---a nonlinear equalization method for reducing equalizer noise enhancement caused by amplitude distortion. Equalization is performed at the transmitter using precoding coefficients provided by the remote modem. |
TX/RX Shaping | TX/RX shaping---a method by which the noise margin of a modem signal can be maximized by forming signal constellations in high-dimensional spaces thereby reducing the average signal power. V.34 modems use a shell mapping mechanism to achieve a near-spherical signal constellation, yielding a shaping gain of around 1 dB. |
TX Preemphasis Index | TX pre-emphasis index---reads the remote modem's PRE-emphasis Request byte value. Pre-emphasis is a linear equalization method where the transmit signal spectrum is shaped to compensate for amplitude distortion. The pre-emphasis filter is selected using a filter index provided by the remote modem; the filters conform to the 11 types outlined in the ITU specifications for the given operating mode. |
Secondary Channel2 | Secondary channel---tells whether the secondary channel is on or off. The auxiliary channel is a reduced bandwidth data channel which, along with the primary channel, is multiplexed into the bit stream transmitted by the modem. Data conveyed in the auxiliary channel is independent from the primary channel and may consist of secondary channel data and modem control data. The secondary channel is a portion of the auxiliary channel that is made available to the user. |
| Line Impairments | |
TX Lvl REG | Transmit level register---tells what transmit level the modem is configured for. Given in dBm (decibels referenced to 1 milliwatt through 600 ohms). |
TX Lvl RAM | Transmit level RAM---tells what amount of transmit level gain the modem is configured for. The gain may be positive or negative and is used to adjust the transmit level separately from the transmit level configuration. Given in dBm. |
Tx Lvl Reduction TX Lvl Reduction | Transmit level reduction---tells what, if any, reduction in transmit level (power drop) has been negotiated by the modems during handshake. Given in dBm. Valid in V.34 mode only. |
TX Lvl | Transmit level ---tells what transmit level the modem actually uses; consists of the configured level plus the tx level gain minus the negotiated power drop. Given in dBm. |
RX Lvl | Receive level---tells what signal level the modem receiver is detecting. Given in dBm. The following table gives a range of common values for V.34: -15 to -25 dBm (excellent/optimum) |
Signal/Noise Ratio S/NR | Signal/noise ratio---tells what ratio or margin exists between the received signal level and the noise level detected by the receiver. Given in dBm. The following table gives a range of common values versus connect speed (V.34): SNR Typical V.34 connect speed * >=46 dBm 33600 45 dBm 31200 44 dBm 28800 42 dBm 26400 39 dBm 24000 35 dBm 21600 32 dBm 19200 31 dBm 16800 29 dBm 14400 27 dBm 12000 24 dBm 9600 22 dBm 7200 19 dBm 4800 16 dBm 2400
* These are empirical values measured in the absence of other impairments. Actual values may vary. Ideal conditions use ISDN-PRI. |
Signal/distortion ration S/DR | Signal/distortion ratio---tells what ratio or margin exists between the received signal level and the harmonic distortion level detected by the receiver. |
Eye Quality EQM | Eye quality measurement---represents the quality of the analog signal. A low number indicates good quality with 0 being the best possible; a high value is considered poor. The modem uses EQM in its rate decision mechanism. Given as a hex number. The following table gives a range of common values (V.34): < 1000 (good) to 2000 (fair) to 3000 (poor) |
AVG EQM | Average eye quality---the output of the EQM averaging mechanism. Initial value is 0000 Hex. |
Lower/Upper Edge | Lower band edge/upper band edge---the channel low and high bandwidth edge estimates (in Hertz) generated by the V.Fast/V.34 handshake probing. |
Phase Jitter Freq | Phase jitter frequency---Phase Jitter is a deviation in the phase of an analog signal having frequency in Hertz and a magnitude in degrees. It results in a pure tone having an associated FM spectrum. In some cases, this spectrum is random and in others it takes the form of discrete multiples and submultiples of AC power frequencies. It can be caused by coupling through from power line associated equipment such as ringing generators. |
Phase Jitter Amp | Phase jitter amplitude---Phase Jitter is a deviation in the phase of an analog signal having frequency in Hertz and a magnitude in degrees. It results in a pure tone having an associated FM spectrum. In some cases, this spectrum is random and in others it takes the form of discrete multiples and submultiples of AC power frequencies. It can be caused by coupling through from power line associated equipment such as ringing generators. |
Far Echo Offset (Phase Roll)2 | Far echo offset---tells how much far end echo frequency offset is present. Given in Hertz. |
Far Echo Lvl | Far echo level---represents the power level of the far echo. The value in dBm can be ascertained by inserting the raw numerical value into this formula: LEVEL= 20LOG(N)-81. |
Round Trip Delay | Round trip delay---shows the amount of time delay that a signal encounters on a given connection. For instance, If a call is routed over a satellite hop, the delay in one direction will be approximately 500 milliseconds; round trip will be approximately 1000 milliseconds. The initial value is 0 milliseconds. |
Dropouts >5dB | Dropouts >5dB---tells how many signal dropouts greater than 5 dBm have occurred during the current connection. The initial value is 0. |
RTRNs Init/Accept | Retrains initiated---tells how many retrains have been initiated by the local modem during the current connection. A retrain is a repetition of most of the modem startup or handshake sequence after the modems have been connected. They usually occur in response to disruptions of the communications channel or user intervention. Retrains accepted---tells how many retrains have been accepted by the local modem during the current connection. |
Rate Changes Inititated/Accepted RRENs Init/Accept | Rate renegotiations initiated---tells how many rate renegotiations have been initiated by the local modem during the current connection. A rate renegotiation is a brief exchange of rate and signal quality information between modems and is used to upshift or downshift the modulation rate after the modems have been connected (much shorter than a full retrain). They usually occur in response to changes in signal quality or user intervention. Rate renegotiations accepted---tells how many rate renegotiations have been accepted by the local modem during the current connection. |
FF Trip/Block Error Rate BLER | Block errors---tells how many block errors occur over a reliable connection (that is, a connection that has a successfully negotiated error correction protocol). |
RBS Counter1 | Robbed bit signaling counter--- the number of bits robbed by the channelized T1 links in the transmission path. |
Digital Pad Detected1 | Digital pad detected---expected values are 0, 3, or 6 dB. |
Avg EQM Filter Pole2 | Average EQM filter pole---determines the bandwidth of the EQM low pass filter. The default is 0000 Hex. |
EQM Gain2 | EQM gain---this number is used to adjust the rate decision mechanism. A higher number results in a more reliable connection; a lower number results in a less reliable connection. The default is 1000 Hex. |
EQM Offset2 | EQM offset---used to adjust the rate decision mechanism. A positive number results in a more reliable connection; a negative (two complement) number results in a less reliable connection. The default is 0000 Hex. |
AVG EQM Baud Interval2 | Average EQM baud interval---refers to the number of symbol intervals or periods between EQM samples. These samples are used to compute a time average of the EQM value. If it is 0, the EQM averaging function is shut off. The default is 0000 Hex. |
AVG EQM Sample Size2 | Average EQM sample size---refers to the number of EQM samples to be run through the EQM LPF. Default is 0000 Hex. |
EQM Threshold Level2 | EQM threshold level---represents the trigger threshold for the Rockwell EQMAT. When the EQM value exceeds this threshold, EQMAT bit is set. The modem uses this for performance decisions. The default is 3000 Hex. |
| 1Supported only on 56K modems (that is, unique to version 3.1.30 firmware). 2Supported on V.34 modems (that is, unique to version 2.2.8 firmware). |
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.
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 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.
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)," and "&Cn (Serial Port DCD Control),".
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
![]() |
Note For 300/1200 Bell devices, the :t89 and associated registers have no effect at this time. |
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--
This section describes the AT commands which have been implemented to accommodate the K56flex and V.90 modulations. See "Connection Result Code Tables," for information related to the modem display connection codes.
![]() |
Note These AT command changes are introduced in firmware version 5.3.30 |
The %Mn command is used to limit the upper (new and faster) modulations. %M sets the upper modulation boundary if you want to limit what modulation is negotiated first. This is normally done to speed up the negotiation process by starting lower down the modulation tree at a modulation that closely matches what the customer expects to use.
The %Bn command is used to limit the speed of the upper (newer/faster) modulations.%M value is set first, then changed to the %B value.
%M4
0 to 4
%Gn%Bn can be used to limit the speeds for a given modulation range selected by %M. This offers an additional level of modulation refinement, but the two (%M and %Gn%Bn) do not have to always be used together. You may only want to play with the speeds without changing the default %M for example, and therefore the latter combination of AT commands are used alone.
AT%G1 is the system default for V.90.
The range is dependent upon the port speed.
Table 88 displays the baud rate interaction for the Kflex EP2 modem.
| %B Setting Values | ||||||||
|---|---|---|---|---|---|---|---|---|
| 44000 V.90 Kflex | 42667 V.90 | 42000 Kflex | 41333 V.90 | 40000 V.90 Kflex | 33600 V.34 | 28800 V.34 VFC | 14400 V.34 VFC V.32 | |
%M4 | Kflex 44000 | Kflex 42000 | Kflex 41333 | Kflex 41333 | Kflex 40000 | V.34- 33600 | V.34- 28800 | V.34- 14400 |
%M3 | Kflex 4000 | Error | Kflex 42000 | Error | Kflex 40000 | V.34- 33600 | V.34- 28800 | V.34- 14400 |
%M2 |
| Error | Error | Error | Error | V.34- 33600 | V.34- 28800 | V.34- 14400 |
%M1 | Error | Error | Error | Error | Error | Error | VFC 28800 | VFC 14400 |
%M0 | Error | Error | Error | Error | Error | Error | Error | V.32- 14400 |
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:

For a copy of CCO's Frequently Asked Questions (FAQ), contact cco-help@cisco.com. For additional information, contact cco-team@cisco.com.
![]() |
Note If you are a network administrator and need personal technical assistance with a Cisco product that is under warranty or covered by a maintenance contract, contact Cisco's Technical Assistance Center (TAC) at 800 553-2447, 408 526-7209, or tac@cisco.com. To obtain general information about Cisco Systems, Cisco products, or upgrades, contact 800 553-6387, 408 526-7208, or cs-rep@cisco.com. |
![]()
![]()
![]()
![]()
![]()
![]()
![]()
Posted: Fri Jan 7 14:22:53 PST 2000
Copyright 2000©Cisco Systems Inc.