Zoltrix AT Command Manual For Zoltrix Model FMHCF56i
Rev 1.01 10/9/1998

Dual Mode V.90/K56Flex 56,000/V.34 33,600 (V.90, K56 Flex, V.34, V.32bis, V.42bis, MNP2-5,10, Caller ID, Software upgradable)



AT Command Format

With the single exception of the A/ command, all commands to the modem begin with the characters AT, and end with a
carriage return character, hence the name AT commands. The general format of an AT command is: AT<command string>
where <command string> represents zero or more commands described in this manual. The <command string> can be null,
resulting in the simple sequence "AT". This sequence, often called the attention command, is useful for checking that
communication is established between an application program and the modem. The response to the AT command is always
OK, providing positive indication of proper operation. It may be useful to issue the AT command several times, with a brief
pause (100 ms. or so) between commands, until the OK response is received. Since the AT command string has no other
effect except to elicit the OK response, it can be used whenever the modem is in command mode. The AT portion of an AT
command can be in upper case or lower case, but not mixed case, thus AT or at, but not At or aT". The <command string>
portion is independent of case. The <command string> may contain space characters, which are ignored.

Your Zoltrix MODEM has been pre-set at the factory for optimum performance.
All defaults are set to allow the modem to negotiate the best possible connection with highest quality, data compression, and error correction.



DEFAULT INIT STRING
The Default INIT string used at the factory and stored into the modem is as follows:

            AT&F&C1&D2
Because the modem was initialized at the factory, you could use an initialization (INIT) string of:

            ATZ

Note:   This command resets the modem to the stored settings. If the settings have been changed by software or manually, this INIT string may not work correctly.

You could change the INIT string in all of your software packages to either of the two previous examples. The first example is the best to use because some software may change the values stored in the modem.

If you want to custom configure your stored profiles, we suggest that you always start out with an AT&F&C1&D2 before customizing other commands. This string will reset the modem to the factory defaults as well as reset some other basic settings.

If modem performance suffers after modifying settings, send the INIT string above (AT&F&C1&D2) to the modem.



PERFORMANCE ISSUES

To get optimum performance from your Zoltrix MODEM, the phone line quality over which you are transmitting and receiving must be reliable and relatively free of "noise". If you have very noisy lines you may be able to get a good connection by forcing the modem to connect at a lower speed. Refer to the +MS command and Limiting the Modems Top Speed for information on controlling the modems speed.



LIMITING THE MODEMS TOP SPEED

If you experience problems connecting to slower modems (2400 or 1200bps), you may need to instruct your modem to limit the top speed to attempt. You may also need to limit the top speed the modem attempts to something less than 33,600bps, even when calling another 33,600 modem, because of the line noise in your area. If you don't, you may experience "garbage" or a "NO CARRIER" message.
This should not be neccassary in most cases, but, there are some 2400bps and 1200bps or even 9600bps modems you may not connect to without using  the following method:
 

  • 1. Use the +MS= command. AT+MS=V34,1,19200,24000 will set the modem to use V.34 modulation, automode detection, with 19,200bps as the lowest transmit connection rate acceptable, and 24,400 as the highest transmit connection rate attempted.
  • AT+MS=V34,1,2400,24000 will set the modem to use V.34 modulation, automode detection, with 2,400bps as the lowest transmit connection rate acceptable, and 24,000 as the highest transmit connection rate attempted.
    Note: See the +MS= command for more details and examples.

AT Command Set
Command

 


AT Command Set (& Commands)
Command
Function
&Cn
Data carrier detect (DCD) signal
&C0 Forces DCD signal to be on at all times.
&C1 DCD on indicates presence of data carrier. (REQUIRED BY MOST SOFTWARE)
&Dn
DTR Option
This command interprets the ON to OFF transition of the DTR signal from the DTE in accordance with the parameter supplied.
&D0
Modem ignores DTR.
&D1
Upon an on-to-off transition of DTR, the modem enters online command state and 
issues an OK result code; the call remains connected.
&D2
Upon an on-to-off transition of DTR, the modem instructs the underlying modem to perform an orderly cleardown of the call. The disposition of any data in the modem pending transmission to the remote modem is controlled by the +ETBM parameter; otherwise, this data is sent before the call is cleared, unless the 
remote modem clears the call first (in which case pending data is discarded). The modem disconnects
&F
Restore Factory Configuration (Profile)
&F
Restore factory configuration 0.
&Gn
Select Guard Tone
This command causes the modem to generate the guard tone selected by this command according to the parameter supplied (DPSK modulation modes only). This command may not be permitted in some countries.
&G0 Disables guard tone.
&G1
Disables guard tone.
&G2 Selects 1800 Hz guard tone.
&Pn
Select Pulse Dial Make/Break Ratio
This command determines the make/break ratio used during pulse dialing.
&P0
Selects 39%-61% make/break ratio at 10 pulses per second.
&P1
Selects 33%-67% make/break ratio at 10 pulses per second.
&P2
Selects 39%-61% make/break ratio at 20 pulses per second.
&P3
Selects 33%-67% make/break ratio at 20 pulses per second.
&V
Display Current Configuration and Stored Profiles
Reports the current (active) configuration, the stored (user) profiles, and the first four stored telephone numbers. The stored profiles and telephone numbers are not displayed if the NVRAM is not installed or is not operational as detected by the NVRAM test during reset processing.
Example:

AT&V 
ACTIVE PROFILE: 
E1 L1 M1 Q0 T V1 X4 &C1 &D2 &G2 &T0 &P0 
S00:000 S01:000 S02:043 S03:013 S04:010 S05:008 S06:002 S07:050 S08:002 
S10:014 S12:050 S16:000 S18:000 S29:070 
 
STORED PROFILE 0: 
E1 L1 M1 Q0 T V1 X4 &C1 &D2 &G0 &T0 &P0 
S00:000 S02:043 S06:004 S07:050 S08:002 S10:014 S12:050 S18:000 S28:000 
S29:000 
 
OK
&Wn
Store Current Configuration
Saves the current (active) configuration (profile), including S-Registers, in the user profile in NVRAM as denoted by the parameter value. This command will yield an ERROR message if the NVRAM is not installed or is not operational as detected by the NVRAM test.

The current configuration is comprised of a list of storable parameters illustrated in the &V command. These settings are restored to the active configuration upon receiving an Z command or at power up.
&W0
Store the current configuration as profile 0.

AT Command Set (% Commands)
Command
Function
%En
Enable/Disable Line Quality Monitor and Auto-Retrain or Fallback/Fall Forward

Controls whether or not the modem will automatically monitor the line quality and request a retrain (%E1) or fall back when line quality is insufficient or fall forward when line quality is sufficient (%E2). If enabled, the modem attempts to retrain for a maximum of 30 seconds. 

This command controls whether or not the modem will automatically monitor the line quality and request a retrain (%E1) or a rate renegotiation when line quality merits a change. If enabled, the modem attempts to retrain for a maximum of 30 seconds. 
Syntax 

%E[<value>]

Defined Values 

<value> A decimal number corresponding to the selected option: 

0 = Disable line quality monitor, auto-retrain, and auto-rate renegotiation. 
1 = Enable line quality monitor, auto-retrain, and auto-rate renegotiation. (Default.)

Result Code 

OK <value> = 0 and 1 
ERROR Otherwise.

%L
Line Signal Level 
This command returns a value which indicates the received signal level. The value returned is a direct indication (DAA dependent) of the receive level at the modem data pump (MDP), not at the telephone line connector. For example, 009 = -9 dBm, 043 = -43 dBm, and so on. 
Syntax 

%L

Example

%L 
015

Result Code 

OK

%Q
Line Signal Quality 
This command returns a value which indicates the line signal quality (DAA dependent). Returns the higher order byte of the EQM value. Based on the EQM value, retrain or rate renegotiation may be initiated if enabled by %E1. 

Example

    AT%Q 
    015

Result Code 

OK If connected. 
ERROR If not connected, or connected in 300 bps, V.23, or fax modes.


AT Command Set (AT+ Commands)
Command
Function
+FCLASS Select Active Service Class 
This command selects the active service class (mode). 
Syntax 

+FCLASS=<mode>

Defined Values 

<mode> Decimal number which corresponds to the selected service class. 
Command options: 

0 Select Data Mode (see Section 3). (Default.) 
1 or 1.0 Select Facsimile Class 1.0 Mode (see Section 4) 
8 Select Voice Mode (see Section 5) 
80 Select VoiceView Mode (see Section 5)

Result Codes 
OK For <mode> = 0, 1, 1.0, 8, and 80 as supported by the Product Configuration File. 
ERROR Otherwise. 
Reporting Current or Selected Values 
Command: +FCLASS? 
Response: +FCLASS: <mode> 
Example: +FCLASS: 0 For the default setting. 
Reporting Supported Range of Parameter Values 
Command: +FCLASS=? 
Response: +FCLASS: (<mode> range) 
Example: +FCLASS: (0, 1,1.0,8, 80)

+GMI Request Manufacturer Identification 
This command causes the modem to report the modem product manufacturer as provided by the Product Configuration File. 
Syntax 

+GMI

Response 

ROCKWELL 
OK

+GMM Request Model Identification 
This command causes the modem to report the modem product model as provided by the Product Configuration File. 
Syntax 

+GMM

Typical Response 

RC56HCF 
OK

+GMR Request Revision Identification 
This command causes the modem to report the modem version, revision level or date as provided by the Product Configuration File. 
Syntax 

+GMR

Typical Response 

RC56HCF R6775 V2.0 5/29/97 
OK

+GSN Request Product Serial Number Identification 
This command causes the modem to report the modem product model serial number as provided by the Product Configuration File. 
Syntax 

+GSN

Typical Response 

VX.XXX-serial number 
OK

+GOI Request Global Object Identification 
This command causes the modem to transmit one or more lines of information text identifying the device, based on the ISO system for registering unique object identifiers. Typically, the text consists of a single line containing numeric strings delimited by period characters. The general format of object identifiers is defined in Section 28 of ITU-T Recommendation X.208; the encoding rules are defined in ITU-T Recommendation X.209. 
Syntax 

+GOI

Typical Response 

TBD 
OK

+GCAP Request Complete Capabilities List 
This extended-format command causes the modem to transmit one or more lines of information text listing additional capabilities command +<name>s , which is intended to permit the user to identify the overall capabilities of the modem. In particular, if the modem implements a particular modem control standard that uses Extended Syntax Commands, and if that modem control standard includes command(s) that indicate general capabilities, the +<names>(s) of those commands will be reported to the modem in response to a +GCAP command. 
Syntax 

+GCAP

Example Responses 
+GCAP: +FCLASS, +MS, +ES, +DS, for a data modem that supports all capabilities listed 
Where: 
+FCLASS   T.class1, +F (Class 1 Facsimile modem Control) 
+MS           +M commands (Modulation Control: +MS and +MR commands) 
+ES            +E commands (Error Control: +ES, +EB, +ER, +EFCS, +ETBM) 
+DS           +D commands (Data Compression: +DS and +DR)

+IFC DTE-Modem Local Flow Control 
This extended-format compound parameter controls the operation of local flow control between the DTE and the modem during the data state when V.42 error control is used, or when fallback to non-error control mode is specified to include buffering and flow control. It accepts two numeric subparameters. 
Syntax 

+IFC=[<modem_by_DTE>[,<DTE_by_modem>]]

Defined Values 
<modem_by_DTE> Specifies the method to be used by the DTE to control the flow of received data from the modem. 

0 = None. 
1 = XON/XOFF on transmitted data (XON/XOFF on transmit data); do not pass XON/XOFF characters to the remote modem. 
2 = Circuit 133 (Ready for Receiving). (Default.) 
3 = XON/XOFF on transmitted data with XON/XOFF characters being passed through to the remote modem in addition to being acted upon for local flow control.

<DTE_by_modem> Specifies the method to be used by the modem to control the flow of transmitted data from the DTE. 

0 = None. 
1= XON/XOFF on received data. 
2 = CTS/RTS. (Default.)

Reporting Current or Selected Values 
Command: +IFC? 
Response: +IFC: <modem_by_DTE>,<DTE_by_modem> 
Example: +IFC: 2,2 for the defaults. 
Reporting Supported Range of Parameter Values 
Command: +IFC=? 
Response: +IFC: (<modem_by_DTE> range),(<DTE_by_modem> range) 
Example: +IFC: (0-3),(0-2)

+ILRR DTE-Modem Local Rate Reporting 
This extended-format numeric parameter controls whether or not the extended-format +ILRR:<rate> information text is transmitted from the modem to the DTE. 
Syntax 

+ILRR=<value>

Defined Values 
<value> Decimal number corresponding to the selected option. 

0 Disables reporting of local port rate (+ILRR: is not transmitted). 
1 Enables reporting of local port rate (+ILRR: is transmitted).

Reporting Current or Selected Values 
Command: +ILRR? 
Response: +ILRR: <current value> 
Example: +ILRR: 0 For the default setting 
Reporting Supported Range of Parameter Values 
Command: +ILRR=? 
Response: +ILRR: (<value> range) 
Example: +ILRR: (0,1) 
Reported Rate 
The <rate> reported represents the current (negotiated or renegotiated) DTE-modem rate. If enabled, the intermediate result code is transmitted after any modulation, error control or data compression reports are transmitted, and before any final result code (e.g., CONNECT) is transmitted. The <rate> is applied after the final result code is transmitted. 
The DTE-modem port rate will change only if neither buffered mode nor error controlled means are enabled (+ES=x,0) and if the negotiated carrier rate (+MRR) does not match the current DTE-modem port rate (autodetected from the previous command line). 
Syntax 

+ILRR: <rate>[,<rx_rate>]

Defined Values 

<rate> Decimal value representing the current (negotiated or renegotiated) DTE-modem rate: 0, 300, 1200, 2400, 4800, 9600, 19200, 38400, 57600, or 115200 
<rx_rate> Optional decimal value reporting the RXD rate, if it is different from the TXD rate: 0, 300, 1200, 2400, 4800, 9600, 19200, 38400, 57600, or 115200

Example 

+ILRR: 19200

+H Enable/Disable Video Ready Mode 
This command enables or disables Rockwell Video Ready Mode. 
Syntax 

+H[<value>]

Defined Values 
<value> Decimal number corresponding to the selected option. 

0 Disable video ready mode. 
16 Enable video ready mode.

Result Codes 
OK <value> = 0 or 16. 
ERROR Otherwise.

+ETBM Call Termination Buffer Management 
This extended-format compound parameter controls the handling of data remaining in modem buffers upon call termination. 
It accepts three numeric subparameters: 
Syntax 

+ETBM=[<pending_TD>[,<pending_RD>[,<timer>]]]

Defined Values 

<pending_TD> Decimal number 0 specifying that disconnect will occur immediately and all buffered transmit data will be discarded when the local DTE requests call disconnection. 
<pending_RD> Decimal number 0 specifying that disconnect will occur immediately and all buffered receive data will be discarded when the local DTE requests call disconnection. 
<timer> Decimal number 0 specifying that the modem will not attempt to deliver the buffered data before abandoning the attempt and discarding remaining data.

Reporting Current or Selected Values 
Command: +ETBM? 
Response: +ETBM: <pending_TD>,<pending_RD>,<timer> 
Example: +ETBM: 0,0,0 
Reporting Supported Range of Parameter Values 
Command: +ETBM=? 
Response: +ETBM: (<pending_TD> range),(<pending_RD> range), (<timer> range) 
Example: +ETBM: (0),(0),(0)

+ER Error Control Reporting 
This extended-format numeric parameter controls whether or not the extended-format "+ER: " intermediate result code is transmitted from the modem to the DTE. 
+ER=[<value>] 
Syntax 

+ER=[<value>]

Defined Values 

<value> A decimal number corresponding to the selected error control option: 

0 = Error control reporting disabled (no +ER intermediate result code transmitted). 
1 = Error control reporting enabled (+ER intermediate result code transmitted). (Default.)

Reporting Current or Selected Values 
Command: +ER? 
Response: +ER: <current value> 
Example: +ER: 1 for the default setting 
Reporting Supported Range of Parameter Values 
Command: +ER=? 
Response: +ER: (<value> range) 
Example: +ER: (0,1) 
+ER: <type> 
The +ER: <type> reported represents the current (negotiated or renegotiated) modem-modem error control type. If enabled, the intermediate result code is transmitted at the point during error control negotiation (handshaking) at which the modem has determined which error control protocol will be used (if any), before the final result code (e.g., CONNECT) is transmitted. The format of this result code is: 
The +ER intermediate result code, if enabled, is issued after the Modulation report (+MCR and +MRR) and before the Data Compression Report (+DR). 
Syntax 

+ER: <type>

Defined Values 

<type> An alphanumeric code corresponding to the selected protocol. 

NONE Error control is not in use. 
LAPM V.42 LAPM protocol is in use. 
ALT MNP is in use.

Example 

+ER: LAPM

+MR Modulation Reporting Control 
This extended-format numeric parameter controls whether or not the extended-format +MCR:<carrier> and +MRR:<rate> intermediate result codes are transmitted from the modem to the DTE. If enabled, +MCR:<carrier> and +MRR:<rate> intermediate result codes represent the current (negotiated or renegotiated) modulation <carrier> and <rate> that are transmitted at the point during connect negotiation (handshaking) at which the modem has determined which modulation and rate will be used, i.e., before any Error Control or Data Compression reports are transmitted, and before any final result code (e.g., CONNECT) is transmitted. 
Syntax 

+MR=[<value>]

Defined Values 

<value> A decimal number corresponding to the selected option: 

0 = Disables reporting of modulation connection (+MCR: and +MRR: are not transmitted). 
1 = Enables reporting of modulation connection (+MCR: and +MRR: are transmitted). (Default.)

Reporting Current or Selected Values 
Command: +MR? 
Response: +MR: <current value> 
Example: +MR: 1 For default setting 
Reporting Supported Range of Parameter Values 
Command: +MR=? 
Response: +MR: (<value>range) 
Example: +MR: (0,1) 

The format of this information text is: 
+MCR: Report Syntax 
Response: +MCR: <carrier> 

<carrier> Alphanumeric code corresponding to the reported carrier. Defined values are: 

B103 For Bell 103 
B212 For Bell 212 
V21 For V.21 
V22 For V.22 
V22B For V.22bis 
V23C For V.23 
V32 For V.32 
V32B For V.32bis 
V34 For V.34 
K56FLEX For K56flex 
V90 For V.90

+MRR: Report Syntax 
Response: +MRR: <tx_rate>,<rx_rate> 

<tx_rate> Decimal transmit rate in bits/s. 
<rx_rate> Decimal receive rate in bits/s.

Example: +MRR: 28600, 48000

+ES Error Control and Synchronous Mode Selection 
This extended-format command specifies the initial requested mode of operation when the modem is operating as the originator, optionally specifies the acceptable fallback mode of operation when the modem is operating as the originator, and optionally specifies the acceptable fallback mode of operation when the modem is operating as the answerer. It accepts three numeric subparameters: 
Syntax 

+ES=[<orig_rqst>[,<orig_fbk>[,<ans_fbk>]]]

Defined Values 

<orig_rqst> Decimal number which specifies the initial requested mode of operation when the modem is operating as the originator. The options are: 

1 Initiate call with Normal Mode (also referred to as Buffered Mode or Direct Mode) only. 
2 Initiate V.42 without Detection Phase. If V.8 is in use, disable V.42 Detection Phase. 
3 Initiate V.42 with Detection Phase. (Default.) 
4 Initiate MNP. 
6 Initiate V.80 Synchronous Access Mode when connection is completed, and Data State is entered. (See +ESA and +ITF commands.)

<orig_fbk> Decimal number which specifies the acceptable fallback mode of operation when the modem is operating as the originator. 

0 LAPM, MNP, or Normal Mode error control optional. (Default.) 
2 LAPM or MNP error control required; disconnect if error control is not established. 
3 LAPM error control required; disconnect if error control is not established. 
4 MNP error control required; disconnect if error control is not established.

<ans_fbk> Decimal number which specifies the acceptable fallback mode of operation when the modem is operating as the answerer or specifies V.80 Synchronous Access Mode. 

1 Error control disabled, use Normal Mode. 
2 LAPM, MNP, or Normal Mode error control optional. (Default.) 
4 LAPM or MNP error control required; disconnect if error control is not established. 
5 LAPM error control required; disconnect if error control is not established. 
6 MNP error control required; disconnect if error control is not established. 
8 Initiate V.80 Synchronous Access Mode when connection is completed, and Data State is entered (see +ESA and +ITF commands).

Examples 

+ES=6 Enable V.80 Synchronous Access Mode originator 
+ES=,,8 Enable V.80 Synchronous Access Mode answerer 
+ES=6,,8 Enable V.80 Synchronous Access Mode originator and answerer 
+ES=3 Enable V.42 with Detection Phase originator. Disable V.80 Synchronous Access Mode originator. 
+ES=,,2 Allow LAPM, MNP, or Normal Mode connection answerer. Disable V.80 Synchronous Access Mode answerer. 
+ES=3,,2 Enable V.42 with Detection Phase originator, allow LAPM, MNP, or Normal Mode connection answer. Disable Synchronous Access Mode originator and answerer.

Reporting Current or Selected Values 
Command: +ES? 
Response: +ES: <orig_rqst>,<orig_fbk>,<ans_fbk> 
Example: +ES: 3,0,2 For default settings. 
+ES: 6,0,8 For V.80 Synchronous Access Mode originator and answerer. 
Reporting Supported Range of Parameter Values 
Command: +ES=? 
Response: +ES: (<orig_rqst> range),( <orig_fbk> range), (<ans_fbk> range) 
Example: +ES: (1-4,6),(0,2-4),(1-2, 4-6,8)

+EB Break Handling in Error Control Operation 
This extended-format compound parameter controls the break handling in V.42 operation. It accepts three numeric subparameters: 
Syntax 

+EB=[<break_selection>[,<timed>[,<default_length>]]]

Defined Values 

<break_selection> Decimal number 0 specifying that break is to be ignored, i.e., not signaled to remote DCE. 
<timed> Decimal number 0 specifying that any transmitted V.42 L-SIGNAL will not indicate break signal length 
<default_length> Decimal number 0 specifying that break is not delivered to the DTE.

Reporting Current or Selected Values 
Command: +EB? 
Response: +EB: <break_selection>,<timed>,<default_length><CR> 
Example: +EB: 0,0,0 For default settings. 
Reporting Supported Range of Parameter Values 
Command: +EB=? 
Response: +EB: (<break_selection> range),(<timed> range), (default_length> range) 
Example: +EB: (0),(0),(0)

+ESR Selective Repeat 
This extended-format numeric parameter controls the use of the selective repeat (SREJ) option in V.42. 
Syntax 

+ESR=[<value>] Decimal number 0 specifying that SREJ is not used.

Example

+ESR: (0) For default settings.

+EFCS 32-bit Frame Check Sequence 
This extended-format numeric parameter controls the use of the 16-bit or 32-bit frame check sequence (FCS) option in V.42. 
Syntax 

+EFCS=[<value>]

Defined Values 

<value> Decimal number 0 specifying the use of the 16-bit FCS specified in V.42.

Reporting Current or Selected Values 
Command: +EFCS? 
Response: +EFCS: <value> 
Example: +EFCS: 0 For default setting. 
Reporting Supported Range of Parameter Values 
Command: +EFCS=? 
Response: +EFCS: (<value> range) 
Example: +EFCS: (0)

+A8E V.8 and V.8bis Operation Controls 
This command is defined for two conditions: as a parameter while the modem is on-hook, and as an action command while the modem is off-hook. If enabled, V.8 negotiation does not preclude simultaneous implementation of other negotiation means (e.g., V.8bis, V.18, V.32bis Annex A). 
This command is a compound parameter if issued while the modem is on-hook, used to precondition V.8 and V.8bis originating and answering operation. It is issued by the DTE before the Dial (D) or Answer (A) command, regardless of the state of the +FCLASS parameter. 

This command is an action command if issued while the modem is off-hook, to (re)start V.8 or V.8bis negotiation. For example, if initial V.8 negotiation failed, but subsequent T.30 negotiation indicated V.8 capability, this command may be used to initiate V.8 negotiation. 
Syntax 

+A8E=<v8o>,<v8a>,<v8cf>[,<v8b>][,<cfrange>][,<protrange>]

Defined Values 

<v8o> Decimal number which enables/disables issuance of +A8 x indications during modem-controlled V.8 origination negotiation 

1 = Enable DCE-controlled V.8 origination negotiation without +A8x indications. (Default.) 
6 = Enable DCE-controlled V.8 origination negotiation with +A8 x indications.

<v8a>= Decimal number which enables/disables issuance of +A8 x indications during modem-controlled V.8 answer negotiation. 

1 = Enable DCE-controlled V.8 answer negotiation without +A8x indications. (Default.) 
5 = Enable DCE-controlled V.8 answer negotiation with +A8 x indications.

<v8c>= Set the V.8 CI signal call function to the hexadecimal octet value X. 

<v8b>= Decimal number which enables/disables V.8bis negotiation. 

0 = Disable V.8bis negotiation. (Default.) 
1 = Enable DCE-controlled V.8bis negotiation. 
2 = Enable DTE-controlled V.8bis negotiation.

<cfrange>= “<string of values>“. Applicable only for <v8a>=5 (not supported). 
< protrange >= “<string of values>“. Applicable only for <v8a>=5 (not supported).

Default values: 1,1,,1,"","" 
The ATD and ATA commands behave as specified in §6.3.1/V.25ter and §6.3.5/V.25ter, respectively, and +A8n indications are not generated by the modem. 
For subparameter values <v8o>=6 and <v8a>=5, the +A8I, +A8C, +A8A, +A8J, and +A8M indications are issued during the course of the V.8 session to notify the DTE when the relevant V.8 signals are received. The modem controls the V.8 ession, however, and the +A8M command is not used. 
Reporting Current or Selected Values 
Command: +A8E? 
Response: +A8E: <v8o>,<v8a>,<v8cf>[,<v8b>][,<cfrange>][,<protrange>] 
Example: +A8E: 1,1,,1,"","" For the defaults 
Reporting Supported Range of Parameter Values 
Command: +A8E=? 
Response: +A8E: (<v8o> range),(<v8a> range), (maximum size of v8cf in octets), (<v8b> range),(<cfrange> option bit range),(<protrange> option bit range) 
Example: +A8E: (1,6),(1,5),(1),(0),(1,6),(1)

+A8M Send V.8 Menu Signals 
This command, applicable only in DTE-controlled V.8, directs the modem to send a V.8 CM or JM signal using the specified hexadecimal coded string. If the modem can decode the menu octet string, and if it cannot implement a specified feature, the modem reports an ERROR final result code, but stays in V.8 operation awaiting another command. 
Syntax 

+A8M=<hexadecimal coded CM or JM octet string>

+A8T Send V.8bis Signal and/or Message(s) 
This command directs the modem to transmit a V.8bis signal and/or message. The first subparameter selects the V.8bis signal (see Tables 1-3/V.8bis). Values of 0 correspond to no signal sent. The hex coded messages, if provided, are used to generate V.8bis messages. 
Syntax 

+A8T=<signal>[,<1st message>][,<2nd message>][,< sig_en >][,<msg_en>][,<supp_delay>]

Defined Values 

<signal> Decimal number which specifies the V.8bis signal (see Table 3-1). 
 

<signal> Value Description
0 None
1 Initiating MRe
2 Initiating MRd
3 Initiating CRe, low power
4 Initiating CRe, high power
5 Initiating CRd
6 Initiating ESi
7 Responding MRd, low power
8 Responding MRd, high power
9 Responding CRd
10 Responding ESr

 

<1st message> The transmitted V.8bis message frame(s) is specified as hexadecimal octet coded string (A.4.1). Additional messages are delimited by comma characters. Flag generation, flag transparency 0-bit insertion and FCS generation are performed by the modem. If no data is provided by the DTE, no V.21 carrier is generated beyond that used in segment 2. For two concatenated messages, the modem inserts the required preamble between the first and second messages. 

 

<2nd message> See <1st message> description. 

 

<sig_en> Decimal number which specifies enables the modem to search for specified V.8 bis signals: 

0 = Enable detection of initiating signals; 
1 = Enable detection of responding signals; 
2 = Enable detection of both signals.

<msg_en>, Decimal number which disables or enables the modem to search for V.8 bis messages. Note that detection of an ES signal automatically conditions the modem to look for an immediately subsequent V.8 bis message regardless of the setting of <msg_en>; see §A.9.2 

0 = Disables detection of the messages 
1 = Directs the modem to search for V.8 bis messages.

<supp_delay>, Decimal number which disables or enables the modem to insert a 1.5 second delay between the transmitted V.8 bis signal and the subsequent V.8 bis message, if any. 

0 = Disables insertion of a 1.5 second delay. 
1 = Enables insertion of a 1.5 second delay.

Reporting Current or Selected Values 
Command: +A8T? 
Response: +A8T: <signal>[,<1st message>][,<2nd message>][,< sig_en >][,<msg_en>][,<supp_delay>] 
Example: 1,XXXX,YYYY,1,1,1, 
Reporting Supported Range of Parameter Values 
Command: +A8T=? 
Response: +A8T: (<signal> range),(max length of message 1),(max length of message 2),(<sig_en> range) 
Example: +A8T: (0-10) (????),(????),(0-1),(0-1)

+A8I: CI Signal Indication 
This indication is issued by an answering modem, if +A8E,<v8a> ¹ 0, to indicate detection of a V.8 CI signal, and report the recovered Call Function octet(s). 
Indication Syntax 

+A8I:<v8cf><CR>

Defined Values 

<v8cf> A hexadecimal code octet representation of those Call Function octet(s). +A8I:0 indicates that the modem timed out waiting for CI.

Example 

+A8I:0 The modem timed out waiting for CI. 
+A8I:X YYY

+A8C: Calling Tone Indication 
This indication is issued by an answering modem, if +A8E,<v8a> =/ 0, to indicate detection of 1100 Hz or 1300 Hz calling tones, or sigC signals, as defined in T.30, V.8 and in V.25. 
Indication Syntax 

+A8C: <type><CR>

Defined Values 

<type> Decimal number which indicates the corresponding detected calling tone. 

0 The modem concluded answer tone transmission without reporting detection of any calling tone. 
1 CNG tone (1100 Hz) detected. 
2 1300 Hz V.25 data modem calling tone detected. 
3 sigC signal: V.32/V.32 bis AA tone detected.

Example 

+A8C: 1 For CNG tone detected.

+A8A: Answer Signal Indication 
This indication is issued by a calling modem, if +A8E <v8o> ¹ 0, to indicate detection of an answering signal. 
Indication Syntax 

+A8A:<type><CR>

Defined Values 

<type><CR> Decimal number which indicates the corresponding detected answer signal. 

0 The modem timed out waiting for an answering signal. 
1 V.8 ANSam signal (2100 Hz with amplitude modulation) detected. 
2 V.25 answer tone (2100 Hz) detected. 
3 V.25 answer tone with phase reversals detected. (Note) 
4 sigA signal: V.21 Ch2 with flags (e.g., T.30 control preamble) detected. 
5 sigA signal: V.22bis USB1 signal detected. 
6 sigA signal: V.32bis AC signal detected. 
7 sigA signal: V.34 ToneA signal detected.

Example 

+A8A:1 For V.8 ANSam signal (2100 Hz with amplitude modulation) detected.

+A8J: V.8 Negotiation Complete 
This indication is issued by either modem when the negotiation is complete and CJ is sent or detected. An answering modem will issue this on detection of CJ from the remote terminal. A calling modem will send a CJ signal to the remote terminal at the same time as a +A8J indication. +A8J:1 indicates CJ; +A8J:0 indicates that the modem timed out waiting for a CJ signal. 
Indication Syntax 

+A8J:<value><CR>

Defined Values 

<value> Decimal number corresponding to the selected option. 

0 The modem timed out waiting for a CJ signal. 
1 CJ signal sent or detected.

Example 

+A8J:1 For CJ sent to a remote terminal.

+A8M: V.8 Menu Report 
This indication is issued by either modem, during V.8 negotiation, to indicate the contents of a valid received CM or JM signal. A +A8M:0 indicates that the modem timed out waiting for a CM or JM signal. 
Report Syntax 

+A8M:< hex_string>

Defined Values 

< hex_string> CM or JM hexadecimal coded string. A +A8M:0 indicates that the modem timed out waiting for a CM or JM signal.

Example 

A8M:XXX YYY

+A8R V.8bis Signal and Message Reporting 
If enabled by +A8E=,,,[<v8b>=2] command, the modem monitors for V.8 bis signals and messages, and uses the +A8R: intermediate result code response to report that signal. Two concatenated V.8 bis messages are reported with two consecutive <message> indications. 
Report Syntax 

+A8R:<signal>[,[<1st message>]][,<2nd message>]<CR>

Defined Values 

<signal> The V.8 bis signal, if detected, is indicated using a <signal> value (see Table 3-1). Values of 4 and 8 are not reported, i.e., the modem is not expected to discern the power level of received CRe and MRd signals. If a V.8 bis message is detected without a preceding V.8 bis signal, the preamble is reported as a 0 <signal> value. 

<1st message> The contents of valid V.8 bis message(s), if detected, are reported using hexadecimal octet coded string(s) (A.4.1). Flag detection and consumption, flag transparency 0-bit deletion and FCS checking are performed by the modem. The modem does not report invalid messages (e.g., bad FCS). If two consecutive messages are detected but the first is invalid, the modem indicates this with no characters between the first and second comma (e.g., +A8R:<signal>,,<2nd message>). 

<2nd message See <1st message>.

Example 

+A8R:0,XX,YY For a V.8 bis message detected without a preceding V.8 bis signal. 
+A8R:0,XX,YY For a V.8 bis message detected with a preceding V.8 bis signal.

+ESA Configure Synchronous Access Mode 
This extended-format compound parameter controls the manner of operation of the Synchronous Access Mode in the 
modem. 
Enabling Synchronous Access Mode enables the use of the 8-bit command characters defined in Table 9/V.80 of the Draft ITU-T Recommendation V.80 (DATA COMMUNICATION OVER THE TELEPHONE NETWORK; In-Band modem Control and Synchronous Data Modes for Asynchronous DTE). 
Syntax 

+ESA=[<trans_idle>[,<framed_idle>[,<framed_un_ov>[,<hd_auto>[,<crc_type>[,<nrzi_en>[,<syn1>[,<syn2>]]]]]]]]

Defined Values 

<trans_idle> Decimal number which specifies the bit sequence transmitted by the modem when a transmit data buffer underrun condition occurs, while operating in Transparent sub-Mode. The options are: 

0 In Transparent sub-Mode, modem transmits 8-bit SYN sequence on idle. Modem receiver does not hunt for synchronization sequence (default and fixed).

<framed_idle> Decimal number which specifies the bit sequence transmitted by the modem when a transmit data buffer underrun condition occurs immediately after a flag, while operating in Framed sub-Mode. 
The options are: 

0 In Framed sub-Mode, modem transmits HDLC flags on idle (default and fixed).

<framed_un_ov> Decimal number which specifies the actions undertaken by the modem when a transmit data buffer underrun or overrun condition occurs immediately after a non-flag octet, while operating in 
Framed sub-Mode. 

0 In Frmed sub-Mode, modem transmits abort on underrun in middle of frame. (Default.) 
1 In Framed sub-Mode, modem transmits a flag on underrun in middle of frame, and notifies DTE of underrun or overrun.

<hd_auto> Decimal number which specifies whether or not, in V.34 half-duplex operation, additional procedures besides those specified in § 12/V.34 will be performed by the modem when switching from primary channel to secondary channel operation, and vice versa. This subparameter should not be commanded. 

<crc_type> Decimal number which specifies the CRC polynomial used while operating in Framed sub-Mode. 
The options are: 

0 CRC generation and checking disabled. (Default.) 
1 In Framed sub-Mode, use the 16-bit CRC specified in V.42. 
2 In Framed sub-Mode, use the 32-bit CRC specified in V.42.

<nrzi_en> Decimal number which specifies if Non Return to Zero Inverted (NRZI) encoding is to be used by the modem for transmit and receive data. The options are: 

0 NZRI encoding and decoding disabled (default and fixed).

<syn1>, <syn2> Decimal number which specifies the octet value(s) to be used while performing character-oriented framing. <syn1> is to be commanded to 255 (FFh); <syn2> is not to be commanded.

Reporting Current or Selected Values 
Command: +ESA? 
Response: +ESA: <trans_idle>,<framed_idle>,<framed_un_ov>,<hd_auto>,<crc_type>,<nrzi_en>,<syn1>,<syn2> 
Example: +ESA: 0,0,0,,0,0,255, For the defaults. 
Reporting Supported Range of Parameter Values 
Command: +ESA=? 
Response: +ESA: (<trans_idle> range), (<framed_idle> range),(<framed_un_ov> range), (<hd_auto> range), 
(<crc_type> range), (<nrzi_en> range),(<syn1> range), (<syn2> range) 
Example: +ESA: (0),(0),(0-1), ,(0-2),(0),(255)

+ITF Transmit Flow Control Thresholds 
In V.80 Synchronous Access Mode, this optional compound parameter allows the DTE to determine the effective input 
buffer size in the modem for data on transmit data from the DTE, to control the thresholds used for flow control of such data, 
and to control how often the modem reports to the DTE the number of octets in this buffer. Note that the DTE can adjust its 
own thresholds for flow control of data on received data from the modem. 
Syntax 

+ITF=[<off>[,<on>[,<report_period>]]]

Defined Values 

<off> Determines the threshold, in octets, above which the modem will generate a flow off signal. Applicable in Synchronous Access Mode. 
The <off> range is 20 -7000. Default <off> value is 128. 
For the <on> and <off> subparameters, the input buffer is assumed to reside between the modem’s V.24 interface and the Synchronous Access protocol layer; i.e., the buffer count includes all octets, including EM codes, received from the DTE, with the exception of XON and XOFF if these are used to signal <modem-by-DTE> flow control. 
The modem returns the ERROR result code if the DTE specifies that the <off> subparameter be set to a value less than or equal to the <on> subparameter; in this case, the current parameter value settings are set to default values. 

<on> Determines the threshold, in octets, below which the modem will generate a flow on signal. Applicable in Synchronous Access Mode. 

The <on> range is 10 -5000. Default <on> value is 64. 

<report_period> Not supported. A fixed value of zero is used and reported.

Reporting Current or Selected Values 
Command: +ITF? 
Response: +ITF: <off>,<on>,<report_period> 
Example: +ITF: 128,64,0 For default values 
Reporting Supported Range of Parameter Values 
Command: +ITF=? 
Response: +ITF: (<off> range),(<on> range),(<report_period> range) 
Example: +ITF: (20-7000),(10-5000),(0)

+MS Select Modulation 
This extended-format command selects the modulation and, optionally, enables or disables automode, specifies the lowest and highest connection rates, selects m-Law or A-Law codec type, and enables or disables robbed bit signaling generation (server modem) or detection (client modem) using one to five subparameters. 
The command format is: 

+MS=[<carrier>[,<automode>[,<min_tx_rate>[,<max_tx_rate>[,<min_rx_rate>[,<max_rx_rate>]]]]]] 

Notes: 

  • 1. For 14400 bps and lower speeds, the Nn command and S37 register can alternatively be used, in which case the +MS subparameters will be modified to reflect the Nn and S37=x settings. Use of the Nn and S37=x commands is not recommended but is provided for compatibility with existing communication software. (S37 is not updated by the +MS command.)

  • 2. Subparameters not entered (enter a comma only or <CR> to skip the last subparameter) remain at their current values.

Reporting Selected Options 
The modem can send a string of information to the DTE consisting of selected options using the following command: 

    +MS?

The response is: 

    +MS: <carrier>,<automode>,<min_rate>,<max_rate>,<min_rx_rate>,<max_rx_rate>

Note: The current active settings are reported under control of the +MR parameter. 

Example: 

+MS: V90,1,75,33600,75,56000 For default values.

Reporting Supported Options 
The modem can send a string of information to the DTE consisting of supported options using the following command: 

    +MS=?

The response is: 

    +MS: (< carrier> range),(<automode> range),(<min_tx_rate> range),(<max_tx_rate> range),(<min_rx_rate> range),(<max_rx_rate> range)

For example, 

+MS: (B103,B212,V21,V22,V22B,V23C,V32,V32B,V34,K56,V90),(0,1),(75-33600),(75-336 
00),(75-56000),(75-56000) 
For V.21, V.22, V.22bis, V.32 and V.32bis, with Automode. 
 

The modem may also automatically switch to another modulation (automode), subject to the following constraints: 

  • a. The modem may not be able to automatically switch from the current modulation (specified by <carrier>) to some other modulation. For example, there is no standard way to automode from Bell 103 to V.23.
  • b. The DTE may disable automode operation (see <automode>).
  • c. The DTE may constrain the range of modulations available by specifying the lowest and highest rates (see <min_tx_rate> and <max_tx_rate> and <min_rx_rate> and <max_rx_rate> below).

Result Code 
OK               Valid subparameter string 
ERROR        Otherwise.



Subparameter Definitions

  • 1. <carrier> = A decimal number which specifies the preferred modulation (automode enabled) or the modulation (automode disabled) to use in originating or answering a connection. The options are:

 

<carrier>

Modulation

Possible Rates(bps) 

Notes

B103 Bell 103 300  
B212 Bell 212 1200  
V21 V.21 300  
V22 V.22 1200  
V22B V.22 bis 2400 or 1200  
V23C V.23 1200 For V.23, originating modes transmit at 75 bps and receive at 1200 bps; answering modes transmit at 1200 bps and receive at 75 bps. The rate is always specified as 1200 bps.
V32 V.32 9600 or 4800  
V32B V.32 bis 14400, 12000, 9600, 7200, or 4800 Default for RC144
V34 V.34 33600, 31200, 28800, 26400, 24000, 21600, 19200, 16800, 14400, 12000, 9600, 7200, 4800, or 2400 Default for RC336/ RC288
V90 V.90 56000, 54667, 53333, 52000, 50667, 49333, 48000, 46667, 45333, 44000, 42667, 41333, 40000, 38667, 37333, 36000, 34667, 33333, 32000, 30667, 29333, 28000 Default for RC56 with V.90 only or V.90/K56flex loaded
K56 K56flex 56000, 54000, 52000, 50000, 48000, 46000, 44000, 42000, 40000, 38000, 36000, 34000, 32000 Default for RC56 with K56flex only loaded
Notes: 
The modem may also automatically switch to another modulation (automode), subject to several 
constraints: 
  1. The modem may not support some other modulations, regardless of the automode mechanism supported.
  2. The modem may not be able to automatically switch from the current modulation <carrier> to some other modulations, restricted by the selected modulation standard and by the modem manufacturer's technology. For example, there is no standard way to automode from V.32bis to V.27ter.
  3. The DTE may disable automode operation, see <automode> below.
  4. The DTE may constrain the range of modulations available, see <min_tx_rate> and <max_tx_rate> and <min_rx_rate> and <max_rx_rate> below.
  5. The DTE may selectively disable some modulations by reading, editing and writing the +MA parameter (6.4.2).

If the DTE issues a +MS=<carrier> command to the modem, and if the modem supports the +MA 
parameter, the modem will reinitialize the +MA parameter.

 

  • 2. <automode> An optional numeric value which enables or disables automatic modulation negotiation (e.g., ITU-T

  • V.32 bis Annex A or V.8). The default value is enabled if it is defined for the associated
    modulation (e.g., ITU-T V.32 bis, V.8 for V.34); however, there are modulations for which there is
    no automatic negotiation defined (e.g., V.26 bis).

 

<automode> Option Selected Notes
0 Automode disabled  
1 Automode enabled, with V.8 or V.32bis Annex where applicable. Default

 

      For <automode> = 0 (automode disabled, i.e., fixed modulation):

    • 1. If <max_rate> is within the rates supported by the selected modulation, the selected rate

    • is that specified by <max_rate>. For example:

        +MS=V32B,0,1200,4800 selects V.32 bis 4800 bps fixed rate.

    • 2. If <max_rate> is greater than the highest speed supported by the modulation specified

    • by <mod>, the starting rate is the highest rate supported by the selected modulation. For
      example:

        +MS=10,0,2400,14400 selects V.32 bis 14400, 12000, 9600, 7200, or 4800 bps.
         

      For <automode> = 1 (automode enabled, i.e., automatically selected speed and modulation):

    • 1. The modem connects at the highest possible rate in accordance with V.8 bis/V.8, or V.32

    • bis Annex A if V.8 bis/V.8 is not supported by the remote modem.
    • 2. If <max_rate> is greater than the highest rate supported by the modulation specified by

    • <mod>, the modem automodes down from the highest rate of the selected modulation.
      For example:

        +MS=V32B,1,1200,14400 selects automoding down from V.32 bis 14400 bps.

  • 3. <min_tx_rate> is an optional number which specifies the lowest rate at which the modem may establish a transmit

  • connection. The value is decimal coded, in units of bps, e.g., 33600 specifies the highest rate to be 33600 bps. The
  • default is 33600.
  • 4. <max_tx_rate> is an optional number which specifies the highest rate at which the modem may establish a transmit

  • connection. The value is decimal coded, in units of bps, e.g., 33600 specifies the highest rate to be 33600 bps. The
  • default is 33600.
  • 5. <min_rx_rate> Optional numeric values which specify the lowest value at which the modem may establish a connection. If unspecified (set to 0), they are determined by the modulation means selected in the <carrier> and <automode> settings. Values for this subparameter are decimal encoded, in units of bit/s. The value range is 75-56000 in the following increments: 75, 300, 600, 1200, 2400, 4800, 7200, 9600, 12000, 14400, 16800, 19200, 21600, 24000, 26400, 28,000, 28800, 29333, 30667, 31200, 32000 33333, 33600, 34000, 34667, 36000, 37333, 38000, 38667, 40000, 41333, 42000, 42667, 44000, 45333, 46000, 46667, 48000, 49333, 50000, 50667, 52000, 53333, 54000, 54667 or 56000, as permitted for the associated carrier. (Default = Lowest rate supported by the selected carrier.)
  • 6. <max_rx_rate> Optional numeric values which specify the highest value at which the modem may establish a connection. If unspecified, (set to 0) they are determined by the modulation means selected in the <carrier> and <automode> settings and by the current DTE-modem rate. Non-zero values for this subparameter are decimal encoded, in units of bit/s. The value range is 75-56000 in the following increments: 75, 300, 600, 1200, 2400, 4800, 7200, 9600, 12000, 14400, 16800, 19200, 21600, 24000, 26400, 28,000, 28800, 29333, 30667, 31200, 32000 33333, 33600, 34000, 34667, 36000, 37333, 38000, 38667, 40000, 41333, 42000, 42667, 44000, 45333, 46000, 46667, 48000, 49333, 50000, 50667, 52000, 53333, 54000, 54667 or 56000, as permitted for the associated carrier. (Default = Highest rate supported by the selected carrier.)

AT Command Set (Error Detection and Data Compression Commands)
Command
Function
+DS Data Compression 
This extended-format compound parameter controls the V.42bis data compression function if provided in the modem. It accepts four numeric subparameters: 
Syntax 

+DS=[<direction>[,<compr_neg>[,<max_dict>[,<max_string>]]]]

Defined Values 

<direction> Specifies the desired direction(s) of operation of the data compression function; from the DTE point of view. 

0 = Negotiated; no compression (V.42bis P0=0). 
3 = both directions, accept any direction (V.42bis P0=11). (Default.)

<compr_neg> Specifies whether or not the modem should continue to operate if the desired result is not obtained. 

0 = Do not disconnect if V.42bis is not negotiated by the remote modem as specified in <direction>.

<max_dict> Specifies the maximum number of dictionary entries (2048 entries) which should be negotiated (may be used by the DTE to limit the codeword size transmitted, based on its knowledge of the nature of the data to be transmitted). 

<max_string> Specifies the maximum string length (32 bytes) to be negotiated (V.42bis P2).

Reporting Current or Selected Values 
Command: +DS? 
Response: +DS: <direction>,<compr_neg>,<max_dict>,<max_string> 
Example: +DS: 3,0,2048,32 for the defaults and 2048 entry max dictionary. 
Reporting Supported Range of Parameter Values 
Command: +DS=? 
Response: +DS: (<direction> range),(< compr_neg > range),(<max_dict> range),(<max_string> range) 
Example: +DS: (0,3),(0),(2048),(32)

+DR Data Compression Reporting 
This extended-format numeric parameter controls whether or not the extended-format "+DR: " intermediate result code is transmitted from the modem to the DTE. 
Syntax 

+DR=[<value>] 

Defined Values 

<value> decimal number corresponding to the selected option: 

0 = Data compression reporting disabled (no +DR result code transmitted). 
1 = Data compression reporting enabled (+DR result code transmitted). (Default.)

Reporting Current or Selected Values 
Command: +DR? 
Response: +DR: <current value> 
Example: +DR: 1 For the default setting. 
Reporting Supported Range of Parameter Values 
Command: +DR=? 
Response: +DR: (<value> range) 
Example: +DR: (0,1) 
+DR: <type> Intermediate Result Code 
The +DR: <type> reported represents the current (negotiated or renegotiated) modem-modem data compression type. If enabled, the intermediate result code is transmitted at the point after error control negotiation (handshaking) at which the modem has determined which data compression technique will be used (if any) and the direction of operation. The +DR intermediate result code, if enabled, is issued after the Error Control Report (+ER) and before the final result code (e.g., CONNECT). 
The format of this result code is: 
Result Code Syntax 

+DR: <type>

Defined Values 

<type> An alphanumeric code corresponding to the selected option: 

NONE Data compression is not in use. 
V42B V.42bis is in use in both directions. 
ALT MNP 5 compression.

Example 

+DR: V42B




AT Command Set (Voice Commands)
Command
Function
+FCLASS=8  Select Voice Mode 
+FCLASS=8 selects the Voice Mode. The Voice Mode commands and responses described in this section are applicable when command +FCLASS=8. (See +FCLASS for a complete definition.)
+FCLASS=80 Select VoiceView Mode 
+FCLASS=80 selects the VoiceView Mode. The Voice Mode commands and responses described in this section are applicable when command +FCLASS=80. (See +FCLASS for a complete definition.)
+VCID=n Enable/Disable Caller ID 
This command controls the reporting and presentation of data associated with the Caller ID services in the U.S. and Canada in the Incoming Call Line ID (ICLID) data format. Enables or disables Caller ID.
+VCID=0 Disables Caller ID.
+VCID=1 Enables Caller ID with formatted presentation to the DTE. The modem will present the data items in a <Tag><Value> pair format. The expected pairs are data, time, caller code (telephone number), and name.
+VCID=2 Enables Caller ID with unformatted presentation to the DTE. The modem will present the entire packet of information, excluding the leading U's, in ASCII printable hex numbers.
Inquiries 
Reporting Current or Selected Values 
Command: +VCID? 
Response: +VCID: <pmode> 
Example: +VCID: 0 For the default setting. 
Reporting Supported Range of Parameter Values  
Command: +VCID=? 
Response: +VCID: (<pmode> range) 
Example: +VCID: (0,1,2)
Formatted Form Reporting 
The modem presents the data in the <tag> = <value> pair format as described in the table below. Spaces are present on both sides of the equal sign.
Tag Description
DATE DATE = MMDD where MM is the month number (01 to 12) and DD is the day number (01..31).
TIME TIME = HHMM where HH is the hour number (00 to 23) and MM is the minute number (00 to 59).
NMBR NMBR = <number> or P or O where <number> is the telephone number of the caller, where P indicates that the calling number information is not available since the originating caller has requested private service, and where O indicates that the calling number information is not available or out of service at the calling location.
NAME NAME = <listing name> where <listing name> is the subscription name.
MESG MESG = <data tag> <length of message> <data> <checksum> in printable ASCII hex numbers. 
This tag indicates a data item not listed above. The message is only possible for Multiple Message Format.
Notes
  • 1. The modem does not present any Caller ID information if the DCE detects a checksum error in the Caller ID packet.
  • 2. In the event of an unrecognized data tag, the modem will present the data in ASCII hex numbers following the MESG tag.

Example of Formatted Form Reporting 

  • 1. The following example illustrates the standard Caller ID message packet.

  • RING 
    DATE = 0321 
    TIME = 1405 
    NMBR = 5045551234 
    NAME = A N OTHER 
    RING 
    RING

     

  • 2. The following example illustrates the case where the tag of the packet is not recognized by the modem.

  • RING 
    MESG = 060342424231 
    RING 
    RING

Unformatted Form Reporting 
The modem presents all information and packet control information found in the message. The modem, however, excludes 
the leading U's (channel seizure information) from the presentation. The packet is presented in ASCII printable hex numbers, 
the modem does not insert spaces, or line feeds, for formatting between bytes or words of the packet. 
The modem does not detect the checksum of the packet. 
Example of Unformatted Form Reporting 

    RING 
    0412303332323234303539313435353132333435 
    RING 
    RING

+VDID DID 
This command allows the situation where the local telset can connect to a single DID capable telephone line, and the where remote telset can access the local handset through multiple phone numbers. 
Syntax 

+VDID=<digits> <timeout>

Defined Values 

<digits> The maximum number of digits (DTMF, MF, etc.) to expect after notification of an incoming call by the Telco. Decimal 0 is the only valid number. 
<timeout> The time interval to wait after the last modem presented DID digit to wait before assuming that there is no more DID information to follow, and ending the DID digit report. Decimal 0 is the only valid number.

Reporting Current or Selected Values 
Command: +VDID? 
Response: +VDID: <digits> <timeout> 
Example: +VDID: 0,0 For the default setting. 
Reporting Supported Range of Parameter Values 
Command: +VDID=? 
Response: +VDID: (<digits> range),(<timeout> range) 
Example: +VDID: (0),(0)

+VNH Automatic Hang-up Control 
This command enables or disables automatic hangups. 
Syntax 

+VNH=<hook>

Defined Values 

<hook> Decimal number corresponding to the selected option. 

0 The modem enables automatic hangups as is normal in other modes. 
1 The modem disables automatic hangups usually found in the other non-Voice Modes. 
2 The modem disables automatic hangups in the other non-Voice Modes. The modem performs only a “logical” hangup (returns to OK result code).

Reporting Current or Selected Values 
Command: +VNH? 
Response: +VNH: <hook> 
Example: +VNH: 0 For the default setting. 
Reporting Supported Range of Parameter Values 
Command: +VNH=? 
Response: +VNH: (<hook> range) 
Example: +VNH: (0-2) 
Result Codes 

OK <hook> = 0-2. 
ERROR Otherwise.

+VIP Voice Initialize All Parameters 
This command causes the modem to initialize all voice parameters to their default values. 
Syntax 

+VIP<n>

Defined Values 

<n> Decimal number 0 corresponding to the selected option.

Reporting Current or Selected Values 
Command: +VIP? 
Response: +VIP: <n> 
Example: +VIP: 0     For the default setting. 
Reporting Supported Range of Parameter Values 
Command: +VIP=? 
Response: +VIP: (<n> range) 
Example: +VIP: (0) 
Result Codes 

OK <n> = 0. 
ERROR Otherwise.

+VRX Start Modem Receive (Record) 
This command causes the modem to start the voice reception process. 
Syntax 

+VRX<n>

Defined Values 

<n> Decimal number corresponding to the selected option. 

0 Start receive voice without periodic tone production during a voice receive operation. 
1 Start receive voice with periodic tone production during a voice receive operation.

Reporting Current or Selected Values 
Command: +VRX? 
Response: +VRX: <n> 
Example: +VRX: 0 For the default setting. 
Reporting Supported Range of Parameter Values 
Command: +VRX=? 
Response: +VRX: (<n> range) 
Example: +VRX: (0,1) 
Result Codes 

OK <n> = 0 or 1. 
ERROR Otherwise.

+VTS Send Voice Tone(s) 
This command causes the modem to send DTMF tones, single frequency tone, and, optionally, double frequency tones. 
Syntax 

+VTS=<string>

Defined Values 

<string> To be added

Reporting Current or Selected Values 
Command: +VTS? 
Response: +VTS: <freq1>, <freq2>, <dur> 
Example: +VTS: 0 For the default setting. 
Reporting Supported Range of Parameter Values 
Command: +VTS=? 
Response: +VTS: (<freq1> range), (<freq2> range), (<dur> range) 
Example: +VTS: (???) 
Result Codes 

OK <string> = 0 or 1. 
ERROR Otherwise.

+VTX Start Modem Transmit (Playback) 
This command causes the modem to start the voice transmission process. 
Syntax 

+VTX

Result Codes 

CONNECT The modem accepts the command. 
ERROR       The modem is not connected to at least one off-hook telephone line or one non-telephone line.

+VGR Voice Gain Receive (Record Gain) 
This command causes the modem to set the gain for received voice samples. 
Syntax 

+VGR=<gain>

Defined Values 

<gain> Decimal number between 0 and 255 corresponding to the gain.

Reporting Current or Selected Values 
Command: +VGR? 
Response: +VGR: <gain> 
Example: +VGR: 0 For the default setting. 
Reporting Supported Range of Parameter Values 
Command: +VGR=? 
Response: +VGR: <gain> range 
Example: +VGR: 0-255 
Result Codes 

OK <gain> = 0-255. 
ERROR Otherwise.

+VGT Voice Gain Transmit (Playback Volume) 
This command causes the modem to set the volume level. 
Syntax 

+VGT=<level>

Defined Values 

<level> Decimal number (0 and 255) corresponding to the volume level.

Reporting Current or Selected Values 
Command: +VGT? 
Response: +VGT: <level> 
Example: +VGT: 0 For the default setting. 
Reporting Supported Range of Parameter Values 
Command: +VGT=? 
Response: +VGT: <level> range 
Example: +VGT: 0-255 
Result Codes 

OK <level> = 0-255. 
ERROR Otherwise.

+VIT Voice Inactivity Timer (DTE/Modem) 
This command sets the modem’s initial value for the DTE/modem inactivity timer. 
Syntax 

+VIT=<timer>

Defined Values 

<timer> Decimal number(0 and 255) corresponding to the time in units of 1.0 second. A value of 0 disables the timer.

Reporting Current or Selected Values 
Command: +VIT? 
Response: +VIT: <timer> 
Example: +VIT: 0 For the default setting. 
Reporting Supported Range of Parameter Values 
Command: +VIT=? 
Response: +VIT: <timer> range 
Example: +VIT: 0-255 
Result Codes 

OK <timer> = 0-255. 
ERROR Otherwise.

+VLS Analog Source/Destination Selection 
This command causes the modem to select one or more source/destinations of the analog data. 
Syntax 

+VLS=<label>

Defined Values 

<label> Decimal number corresponding to the selected option. 

0 Modem on hook. Phone connected to line 
1 Modem connected to line. 
2 Modem connected to handset 
3 Modem connected to line and handset 
4 Modem connected to speaker 
5 Modem connected to line and speaker 
6 Modem connected to microphone 
7 Speaker and microphone routed to line via modem 
8 Modem connected to speaker 
9 Modem connected to line and speaker 
10 Speaker and microphone routed to line via Modem 
11 Modem connected to microphone 
12 Speaker and microphone routed to line via Modem 
13 Speaker and microphone routed to line via Modem 
14 Modem connected to Headset 
15 Speaker and microphone routed to line via Modem 
16 Enable (Mute) microphone 
17 Disable microphone 
18 Enable (mute) speaker 
19 Disable speaker

Reporting Current or Selected Values 
Command: +VLS? 
Response: +VLS: <label> 
Example: +VLS: 0 For the default setting. 
Reporting Supported Range of Parameter Values 
Command: +VLS=? 
Response: +VLS: <label> range 
Example: +VLS: 0-19 
Result Codes 

OK <label> = 0-19. 
ERROR Otherwise.

+VRA Ringback Goes Away Timer 
This command sets the length of time the modem will wait between ringbacks during call origination before the modem can assume that the remote station has gone off hook. 
Syntax 

+VRA=<interval>

Defined Values 

<interval> Decimal number (0-600) specifying the silence interval time in units of 0.10 second between the end of one ring interval and the start of the next ring interval. A value of 0 forces the modem to report the OK result code immediately after the first Ringback. The range is 0.01 to 60.0 seconds for <interval> = 1 to 600.

Reporting Current or Selected Values 
Command: +VRA? 
Response: +VRA: <interval> 
Example: +VRA: 50 (0.5 seconds) For the default setting. 
Reporting Supported Range of Parameter Values 
Command: +VRA=? 
Response: +VRA: (<interval> range) 
Example: +VRA: (0-600) 
Result Codes 

OK <interval> = 0 -600 
ERROR Otherwise.

+VRN Ringback Never Appeared Timer 
This command sets the length of time the modem will wait between ringbacks during call origination before the modem can assume that the remote station has gone off hook. 
Syntax 

+VRN=<interval>

Defined Values 

<interval> Decimal number (0-60) specifying the time period, in units of 1.0 second, that the modem will wait for Ringback during call origination. A value of 0 forces the modem to report the OK result code immediately after dialing. The range is 1 to 60 seconds for <interval> = 1 to 60.

Reporting Current or Selected Values 
Command: +VRN? 
Response: +VRN: <interval> 
Example: +VRN: 10 (10 seconds) For the default setting. 
Reporting Supported Range of Parameter Values 
Command: +VRN=? 
Response: +VRN: (<interval> range) 
Example: +VRN: (0-60) 
Result Codes 

OK <interval> = 0 -60 
ERROR Otherwise.

+VSD Silence Detection (Quiet and Silence) 
This command causes the modem to set the silence detection sensitivity and the required period of silence before the modem reports silence detected at the end of a voice receive either with the “Presumed End of Message” (QUIT) or “Presumed Hangup (SILENCE) event reports. 
Syntax 

+VSD=<sds>,<sdi>

Defined Values 

<sds> Decimal number corresponding to the selected parameter. 

0 Use +VSM silence compression setting and algorithm for long-term silence detection (if +VSM is in use) or proprietary silence compression setting and algorithm for long-term silence detection (if +VSM is not in use). 
127 Sets less aggressive long-term silence detection independent of presence or use of silence compression. 
128 Sets nominal long-term silence detection independent of presence or use of silence compression. 
129 Sets more aggressive long-term silence detection independent of presence or use of silence compression.

<sdi> Decimal number specifying the required period of silence, in units of 0.1 second, before the modem can report silence detected at the end of a voice receive either with the “Presumed End of Message” (QUIT) or “Presumed Hangup (SILENCE) event reports. A value of 0 disables the modem silence detection. The range is 0.1 to 25.5 seconds for <sdi> = 1 to 255.

Reporting Current or Selected Values 
Command: +VSD? 
Response: +VSD: <sds>,<sdi> 
Example: +VSD: 128, 50 For the default setting. 
Reporting Supported Range of Parameter Values 
Command: +VSD=? 
Response: +VSD: (<sds> range),(<sdi> range) 
Example: +VSD: (0,127,128,129),(0-255) 
Result Codes 

OK <hook> = 0 or 1. 
ERROR Otherwise.

+VSM Compression Method Selection 
This command causes the modem to set the voice compression method, the silence compression sensitivity, and the voice sampling rate. 
Syntax 

+VSM=<cml>,<vsr>,<sds>,<sel>

Defined Values 

<cml> Decimal number identifying the compression method. To be expanded. 
<vsr> <range of values> containing the supported range of voice samples per second of the analog signal. To be expanded. 
<scs> <range of values> containing the supported range of sensitivity settings for voice receives. To be expanded. To be expanded. 
<sel> <range of values> containing the supported range of expansion values for voice transmits.

Reporting Current or Selected Values 
Command: +VSM? 
Response: +VSM: <cml>,<vsr>,<sds>, <sel> 
Example: +VSM: 130,UNSIGNED PCM,8,0,(7200,11025),(127-129),(0)" 
Reporting Supported Range of Parameter Values 
Command: +VSM=? 
Response: +VSM: <cml>, <cmid>, <bps>, <tm>,<vsr>,<sds>, <sel> 

<cml> Decimal number identifying the compression method. 
<cmid> Alphanumeric string describing the compression method. 
<bps> Decimal number defining the average number of bits in the compressed sample not including silence compression. 
<tm> Decimal number (0-X) reporting the time interval, in units of 0.1 second, between timing marks. A value of 0 reports that timing marks are not supported. The range is 1 to 60 seconds for <tm> = 1 to 60. 
<vsr> <range of values> containing the supported range of voice samples per second of the analog signal. 
<scs> <range of values> containing the supported range of sensitivity settings for voice receives. 
<sel> <range of values> containing the supported range of expansion values for voice transmits.

Example: +VSM: 128, ADPCM,2,0,7200,(127-129),(0)<cr><lf> 
129,ADPCM,4,0,7200,(127-129),(0) <cr><lf> 
130,UNSIGNED PCM,8,0,(7200,11025),(127-129),(0) 
Result Codes 

OK Valid range. 
ERROR Otherwise.

+VTD Beep Tone Duration Timer 
This command causes the modem to set the default DTMF/tone generation duration. 
Syntax 

+VTD=<dur>

Defined Values 

<dur> Decimal number specifying the default DTMF/tone generation duration in units of 0.01 second. A value of 0 specifies a manufacturer specific time interval. The range is 0.01 to 5 seconds for <dur> = 1 to 500.

Reporting Current or Selected Values 
Command: +VTD? 
Response: +VTD: <dur> 
Example: +VTD: 0 For the default setting. 
Reporting Supported Range of Parameter Values 
Command: +VTD=? 
Response: +VTD: (<dur> range) 
Example: +VTD: (0-500) 
Result Codes 

OK <dur>= 0-500. 
ERROR Otherwise.

+VDR Distinctive Ring 
This command causes the modem to enable or disable reporting of the ring cadence information and to control the timing of the RING event code report if ring cadence reporting is enabled. 
Syntax 

+VDR=<enable>, <report>

Defined Values 

<enable> Decimal number corresponding to the selected option. 

0 The modem will not report ring cadence information. 
1 The modem will report ring cadence information as specified for the <report> subparameter.

<report> Decimal number specifying ring cadence information report when enabled by the <enable> subparameter. 

0 The modem will produce only DROF and DRON messages. The modem will not produce any RING event codes. The modem will report other call progress event codes as normal. 
Other The modem will produce only DROF and DRON messages. The modem will produce a RING event code after <report>/10 seconds after the falling edge of the ring pulse (i.e., after the DRON report).

Reporting Current or Selected Values 
Command: +VDR? 
Response: +VDR: <enable>,<report> 
Example: +VDR: 0,0 For the default setting. 
Reporting Supported Range of Parameter Values 
Command: +VDR=? 
Response: +VDR: (<enable> range),(<report>range) 
Example: +VDR: (0,1),(0-10) 
Result Codes 

OK <enable>,<report> = (0,1),(0-10) 
ERROR Otherwise.

+VDT Control Tone Cadence Reporting 
This command allows the modem to enable or disable reporting of the control tone cadence information in the frequency band used by the Ringback/Remote Ring, BUSY, and reorder/Fast Busy tones (usually in the 300to 600 Hz range). 
Syntax 

+VDT=<enable>,<report>

Defined Values 

<enable> Decimal number corresponding to the selected option. 

0 The modem will not produce any control tone cadence report. 
1 The modem will produce control tone cadence report as specified for the <report> subparameter.

<report> Decimal number specifying the produced any control tone cadence report when enabled by the <enable> subparameter. 

0 The modem will produce only CPOF and CPON messages. 
Other Reserved.

Reporting Current or Selected Values 
Command: +VDT? 
Response: +VDT: <enable>,<report> 
Example: +VDT: 0,0 For the default setting. 
Reporting Supported Range of Parameter Values 
Command: +VDT=? 
Response: +VDT: (<enable> range),(<report> range) 
Example: +VDT: (0,1),(0) 
Result Codes 

OK <enable>,<report> = (0,1),(0) 
ERROR Otherwise.

+VBT Buffer Threshold Setting 
This command causes the modem to report the <deassert> and <assert> subparameter values as a <compound ranges of values>. The OK result code follows the report. 
Syntax 

+VBT=<deassert>,<assert>

Defined Values 

To be added

Reporting Current or Selected Values 
Command: +VBT? 
Response: +VBT: <deassert>,<assert> 
Example: +VBT: TBD For the default setting. 
Reporting Supported Range of Parameter Values 
Command: +VBT=? 
Response: +VBT: (<deassert> range), (assert>range) 
Example: +VBT: (820-4096),(6144-7372), 8192 
Result Codes 

OK <deassert>,<assert>= 0 or 1. 
ERROR Otherwise.

+VPR Select DTE/Modem Interface Rate (Turn Off Autobaud) 
To be added. 
Syntax 

+VPR=<rate>

Defined Values 

<rate>> To be added.

Reporting Current or Selected Values 
Command: +VPR? 
Response: +VPR: <rate> 
Example: +VPR: 0 For the default setting. 
Reporting Supported Range of Parameter Values 
Command: +VPR=? 
Response: +VPR: (<rate> range) 
Example: +VPR: (0,1) 
Result Codes 

OK <rate> = 0 or 1. 
ERROR Otherwise.

+VSP Speakerphone ON/OFF 
This command turns the speakerphone ON or OFF 
Syntax 

+VSP=<mode>

Defined Values 

<mode> Decimal number corresponding to the selected option. 

0 The speakerphone function is OFF. 
1 The speakerphone function is ON.

Reporting Current or Selected Values 
Command: +VSP? 
Response: +VSP: <mode> 
Example: +VSP: 0 For the default setting. 
Reporting Supported Range of Parameter Values 
Command: +VSP=? 
Response: +VSP: (<mode> range) 
Example: +VSP: (0,1) 
Result Codes 

OK <mode> = 0 or 1. 
ERROR Otherwise.

+VDX Speakerphone Duplex Mode 
This command selects speakerphone half-duplex or full duplex mode. 
Syntax 

+VDX=<mode>

Defined Values 

<mode> Decimal number corresponding to the selected option. 

0 The speakerphone mode is half duplex. 
1 The speakerphone mode is full duplex.

Reporting Current or Selected Values 
Command: +VDX? 
Response: +VDX: <mode> 
Example: +VDX: 0 For the default setting. 
Reporting Supported Range of Parameter Values 
Command: +VDX=? 
Response: +VDX: (<mode> range) 
Example: +VDX: (0,1) 
Result Codes 

OK <mode> = 0 or 1. 
ERROR Otherwise.

+VGM Microphone Gain 
This command causes the modem to set the microphone gain of the speakerphone function. 
Syntax 

+VGM=<gain>

Defined Values 

<gain> Decimal number between 0 and 255 corresponding to the gain.

Reporting Current or Selected Values 
Command: +VGM? 
Response: +VGM: <gain> 
Example: +VGM: 0 For the default setting. 
Reporting Supported Range of Parameter Values 
Command: +VGM=? 
Response: +VGM: <gain> range 
Example: +VGM: 0-255 
Result Codes 

OK <gain> = 0-255. 
ERROR Otherwise.

+VGS Speaker Gain 
This command causes the modem to set the speaker gain of the speakerphone function. 
Syntax 

+VGS=<gain>

Defined Values 

<gain> Decimal number between 0 and 255 corresponding to the gain.

Reporting Current or Selected Values 
Command: +VGS? 
Response: +VGS: <gain> 
Example: +VGS: 0 For the default setting. 
Reporting Supported Range of Parameter Values 
Command: +VGS=? 
Response: +VGS: <gain> range 
Example: +VGS: 0-255 
Result Codes 

OK <gain> = 0-255. 
ERROR Otherwise.


AT COMMAND RESULT CODES
The modem responds to commands from the DTE and to activity on the line by signalling to the DTE in the form of result codes. The result codes that the modem can send are described below.
Two forms of each result code are available: long-form, an English-like "verbose" response, and short-form, a data-like numeric response (included in parentheses following the long-form). The long-form code is preceded and terminated by the sequence < CR> < LF>. The short-form is terminated by < CR>, only with no preceding sequence.
If result messages are suppressed, nothing is returned to the DTE.

OK (0)

The OK code is returned by the modem to acknowledge execution of a command line.

CONNECT (1)
The modem will send this result code upon connecting when:

  • 1. The line speed is 300 bps and the modem has been instructed to report the line speed to the DTE upon connecting, or
  • 2. The DTE speed is 300 bps and the modem has been instructed to report the DTE speed to the DTE upon connecting, or
  • 3. The range of result code responses is restricted by the X command such that no speed reporting is allowed.

RING (2)
The modem sends this result code when incoming ringing is detected on the line. When cellular interface is selected, RING indicates that the cellular phone is receiving an incoming call.

NO CARRIER (3)
The modem sends this result code when attempting to establish a call if:

  • 1. Ringback is detected and later ceases but no carrier is detected within the period of time determined by register S7, or
  • 2. No ringback is detected within the period of time determined by register S7.

This result code is also used when the modem auto-disconnects due to loss of carrier.
Under X0, if busy tone detection is enforced, this result code is used as a response to the detection of busy or circuit busy.
Under X0, if dial tone detection is enforced or selected, this result code is used to indicate that dial tone has not been
detected.

ERROR (4)
The modem returns this result code if the command line contains a syntax error or it is unable to execute a command contained in the command line. It is issued if a command does not exist or if the parameter supplied is outside the permitted range.
Under X0, X1, X2, and X3, this result is used instead of DELAYED and BLACKLISTED.

CONNECT 1200 (5)
For X1, X2, X3, and X4, the modem sends this result code when:

  • 1. The line speed is 1200 bps and the modem has been instructed to report the line speed to the DTE upon connecting, or
  • 2. The DTE speed is 1200 bps and the modem has been instructed to report the DTE speed to the DTE upon connecting.

(Also, see the W command.)

NO DIALTONE (6)
For X2 and X4, the modem sends this result code if it has been instructed to wait for dial tone during dialing but none is
received.
When cellular phone interface is selected, NO DIALTONE indicates that cellular service is not currently available.

BUSY (7)
For X3 and X4, if busy tone detection is enforced, the modem sends this result code when attempting to originate a call if the
busy (engaged) signal is detected on the line.

NO ANSWER (8)
The modem sends this result code when attempting to originate a call if a continuous ringback signal is detected on the line
until the expiration of the timer S7.

CONNECT 0600 (9)
For X1, X2, X3, and X4, the modem sends this result code when:

  • 1. The line speed is 600 bps and the modem has been instructed to report the line speed to the DTE upon connecting, or
  • 2. The DTE speed is 600 bps and the modem has been instructed to report the DTE speed to the DTE upon connecting.

CONNECT 2400 (10)
For X1, X2, X3, and X4, the modem sends this result code when:

  • 1. The line speed is 2400 bps and the modem has been instructed to report the line speed to the DTE upon connecting, or
  • 2. The DTE speed is 2400 bps and the modem has been instructed to report the DTE speed to the DTE upon connecting.

CONNECT 4800 (11)
For X1, X2, X3, and X4, the modem sends this result code when:

  • 1. The line speed is 4800 bps and the modem has been instructed to report the line speed to the DTE upon connecting, or
  • 2. The DTE speed is 4800 bps and the modem has been instructed to report the DTE speed to the DTE upon connecting.

CONNECT 9600 (12)
For X1, X2, X3, and X4, the modem sends this result code when:

  • 1. The line speed is 9600 bps and the modem has been instructed to report the line speed to the DTE upon connecting, or
  • 2. The DTE speed is 9600 bps and the modem has been instructed to report the DTE speed to the DTE upon connecting.

CONNECT 7200 (13)
For X1, X2, X3, and X4, the modem sends this result code when:

  • 1. The line speed is 7200 bps and the modem has been instructed to report the line speed to the DTE upon connecting, or
  • 2. The DTE speed is 7200 bps and the modem has been instructed to report the DTE speed to the DTE upon connecting.

CONNECT 12000 (14)
For X1, X2, X3, and X4, the modem sends this result code when:

  • 1. The line speed is 12000 bps and the modem has been instructed to report the line speed to the DTE upon connecting, or
  • 2. The DTE speed is 12000 bps and the modem has been instructed to report the DTE speed to the DTE upon connecting.

CONNECT 14400 (15)
For X1, X2, X3, and X4, the modem sends this result code when:

  • 1. The line speed is 14400 bps and the modem has been instructed to report the line speed to the DTE upon connecting, or
  • 2. The DTE speed is 14400 bps and the modem has been instructed to report the DTE speed to the DTE upon connecting.

CONNECT 19200 (16)
For X1, X2, X3, and X4, the modem sends this result code when:

  • 1. The line speed is 19200 bps and the modem has been instructed to report the line speed to the DTE upon connecting, or
  • 2. The DTE speed is 19200 bps and the modem has been instructed to report the DTE speed to the DTE upon connecting.

CONNECT 38400 (17)
For X1, X2, X3, and X4, the modem sends this result code upon connecting when the DTE speed is 38400 bps and the
modem has been instructed to report the DTE speed to the DTE upon connecting.

CONNECT 57600 (18)
For X1, X2, X3, and X4, the modem sends this result code upon connecting when the DTE speed is 57600 bps and the
modem has been instructed to report the DTE speed to the DTE upon connecting.

CONNECT 115200 (19)
For X1, X2, X3, and X4, the modem sends this result code upon connecting when the DTE speed is 115200 bps and the
modem has been instructed to report the DTE speed to the DTE upon connecting.

CONNECT 75TX/1200RX (22)
For X1, X2, X3, and X4, the modem returns this result code upon establishing a V.23 originate connection when the modem
has been instructed to report the DCE speed upon connection.

CONNECT 1200TX/75RX (23)
For X1, X2, X3, and X4, the modem returns this result code upon establishing a V.23 answer connection when the modem
has been instructed to report the DCE speed upon connection.

DELAYED (24)
For X4, the modem returns this result code when a call fails to connect and the number dialed is considered 'delayed' due to
country blacklisting requirements.

BLACKLISTED (32)
For X4, the modem returns this result code when a call fails to connect and the number dialed is considered 'blacklisted'.

FAX (33)
The modem returns this result code when a fax modem connection is established in a facsimile mode.

DATA (35)
The modem returns this result code when a data modem connection is established in a facsimile mode.

CARRIER 300 (40)
The modem returns this result code when a 0-300 bps data rate has been detected on the line and carrier reporting has
been enabled. (See S95 and Xn.)

CARRIER 1200/75 (44)
The modem sends this result code when the V.23 backward channel carrier has been detected on the line and carrier
reporting has been enabled. (See S95 and Xn.)

CARRIER 75/1200 (45)
The modem sends this result code when the V.23 forward channel carrier has been detected on the line and carrier reporting
has been enabled. (See S95 and Xn.)

CARRIER 1200 (46)
The modem sends this result code when a 1200 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 2400 (47)
The modem sends this result code when a 2400 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 4800 (48)
The modem sends this result code when a 4800 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 7200 (49)
The modem sends this result code when a 7200 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 9600 (50)
The modem sends this result code when a 9600 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 12000 (51)
The modem sends this result code when a 12000 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 14400 (52)
The modem sends this result code when a 14400 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 16800 (53)
The modem sends this result code when a 16800 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 19200 (54)
The modem sends this result code when a 19200 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 21600 (55)
The modem sends this result code when a 21600 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 24000 (56)
The modem sends this result code when a 24000 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 26400 (57)
The modem sends this result code when a 26400 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 28800 (58)
The modem sends this result code when a 28800 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CONNECT 16800 (59)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 16800 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 21600 (61)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 21600 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 24000 (62)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 24000 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 26400 (63)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 26400 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 28800 (64)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 28800 bps and the
modem has been instructed to report the DTE speed upon connecting.

COMPRESSION: CLASS 5 (66)
This message is sent to the DTE when the modem has connected in MNP Class 5 and COMPRESSION message reporting
has been enabled. (See S95 and Xn.)

COMPRESSION: V.42 bis (67)
This message is sent to the DTE when the modem has connected in V.42 bis and COMPRESSION message reporting has
been enabled. (See S95 and Xn.)

COMPRESSION: NONE (69)
This message is sent to the DTE when the modem has connected without data compression and COMPRESSION message
reporting has been enabled. (See S95 and Xn.)

PROTOCOL: NONE (70)
This message is sent to the DTE when the modem has connected without any form of error correction, and the PROTOCOL
message reporting has been enabled. (See S95 and Xn.)

PROTOCOL: LAPM (77)
This message is sent to the DTE when the modem has connected in the V.42 LAPM mode of error correction, and
PROTOCOL message reporting has been enabled. (See S95 and Xn.)

CARRIER 31200 (78)
The modem sends this result code when a 31200 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 33600 (79)
The modem sends this result code when a 33600 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

PROTOCOL: ALT (80)
This message is sent to the DTE when the modem has connected in the MNP mode of error correction, and PROTOCOL
message reporting has been enabled. (See S95 and Xn.)

PROTOCOL: ALT-CELLULAR (81)
This message is sent to the DTE when the modem has connected in the MNP 10 mode and cellular power level adjustment
is enabled (")M1 or )M2").(See S95 and Xn.)

CONNECT 33600 (84)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 33600 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 31200 (91)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 31200 bps and the
modem has been instructed to report the DTE speed upon connecting.

CARRIER 28000 ()
The modem sends this result code when a 28000 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)
 
CARRIER 29333 ()
The modem sends this result code when a 29333 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 30667 ()
The modem sends this result code when a 30667 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 33333 ()
The modem sends this result code when a 33333 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 34667 ()
The modem sends this result code when a 34667 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 37333 ()
The modem sends this result code when a 37333 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 38667 ()
The modem sends this result code when a 38667 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 41333 ()
The modem sends this result code when a 41333 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 42667 ()
The modem sends this result code when a 42667 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 45333 ()
The modem sends this result code when a 45333 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 46667 ()
The modem sends this result code when a 46667 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 49333 ()
The modem sends this result code when a 49333 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 50667 ()
The modem sends this result code when a 50667 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 53333 ()
The modem sends this result code when a 53333 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 54667 ()
The modem sends this result code when a 54667 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 32000 (150)
The modem sends this result code when a 32000 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 34000 (151)
The modem sends this result code when a 34000 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 36000 (152)
The modem sends this result code when a 36000 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 38000 (153)
The modem sends this result code when a 38000 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 40000 (154)
The modem sends this result code when a 40000 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 42000 (155)
The modem sends this result code when a 42000 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 44000 (156)
The modem sends this result code when a 44000 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 46000 (157)
The modem sends this result code when a 46000 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 48000 (158)
The modem sends this result code when a 48000 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 50000 (159)
The modem sends this result code when a 50000 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 52000 (160)
The modem sends this result code when a 52000 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 54000 (161)
The modem sends this result code when a 54000 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CARRIER 56000 (162)
The modem sends this result code when a 56000 bps data rate has been detected on the line and carrier reporting has been
enabled. (See S95 and Xn.)

CONNECT 32000 (165)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 32000 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 34000 (166)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 34000 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 36000 (167)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 36000 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 38000 (168)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 38000 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 40000 (169)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 40000 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 42000 (170)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 42000 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 44000 (171)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 44000 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 46000 (172)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 46000 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 48000 (173)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 48000 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 50000 (174)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 50000 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 52000 (175)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 52000 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 54000 (176)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 54000 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 56000 (177)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 56000 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 28000 (180)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 28000 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 29333 (181)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 29333 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 30667 (182)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 30667 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 33333 (183)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 33333 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 34667 (184)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 34667 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 37333 (185)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 37333 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 38667 (186)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 38667 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 41333 (187)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 41333 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 42667 (188)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 42667 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 45333 (189)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 45333 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 46667 (190)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 46667 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 49333 (191)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 49333 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 50667 (192)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 50667 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 53333 (193)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 53333 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 54667 (194)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 54667 bps and the
modem has been instructed to report the DTE speed upon connecting.

CONNECT 230400 (20)
For X1, X2, X3, and X4, the modem returns this result code upon connecting when the DTE speed is 230400 bps and the
modem has been instructed to report the DTE speed upon connecting.

+FCERROR (+F4)
This message is sent to the DTE when high speed fax data (V.27, V.29, V.33, or V.17) is expected and a V.21 signal is
received.
 
 

Result Codes
Short Form (Numeric) Long Form (Verbal) n Value in ATXn Command Notes
0 OK x x x x x  
1 CONNECT x x x x x  
2 RING x x x x x  
3 NO CARRIER x x x x x  
4 ERROR x x x x x  
5 CONNECT 1200 1 x x x x  
6 NO DIALTONE 3 3 x x x  
7 BUSY 3 3 3 x x  
8 NO ANSWER x x x x x  
9 CONNECT 0600 1 x x x x  
10 CONNECT 2400 1 x x x x  
11 CONNECT 4800 1 x x x x  
12 CONNECT 9600 1 x x x x  
13 CONNECT 7200 1 x x x x  
14 CONNECT 12000 1 x x x x  
15 CONNECT 14400 1 x x x x  
16 CONNECT 19200 1 x x x x  
17 CONNECT 38400 1 x x x x  
18 CONNECT 57600 1 x x x x  
19 CONNECT 115200 1 x x x x  
20 CONNECT 230400 x x x x x Note 4
22 CONNECT 75TX/1200RX 1 x x x x  
23 CONNECT 1200TX/75RX 1 x x x x  
24 DELAYED 4 4 4 4 x  
32 BLACKLISTED 4 4 4 4 x  
33 FAX x x x x x  
35 DATA x x x x x  
40 CARRIER 300 x x x x x  
44 CARRIER 1200/75 x x x x x  
45 CARRIER 75/1200 x x x x x  
46 CARRIER 1200 x x x x x  
47 CARRIER 2400 x x x x x  
48 CARRIER 4800 x x x x x  
49 CARRIER 7200 x x x x x  
50 CARRIER 9600 x x x x x  
51 CARRIER 12000 x x x x x  
52 CARRIER 14400 x x x x x  

 

Short Form (Numeric) Long Form (Verbal) n Value in ATXn Command Notes
53 CARRIER 16800 x x x x x Note 2
54 CARRIER 19200 x x x x x Note 2
55 CARRIER 21600 x x x x x Note 2
56 CARRIER 24000 x x x x x Note 2
57 CARRIER 26400 x x x x x Note 2
58 CARRIER 28800 x x x x x Note 2
59 CONNECT 16800 1 x x x x Note 2
61 CONNECT 21600 1 x x x x Note 2
62 CONNECT 24000 1 x x x x Note 2
63 CONNECT 26400 1 x x x x Note 2
64 CONNECT 28800 1 x x x x Note 2
66 COMPRESSION: CLASS 5 x x x x x  
67 COMPRESSION: V.42 bis x x x x x  
69 COMPRESSION: NONE x x x x x  
70 PROTOCOL: NONE x x x x x  
77 PROTOCOL: LAPM x x x x x  
78 CARRIER 31200 x x x x x Note 3
79 CARRIER 33600 x x x x x Note 3
80 PROTOCOL: ALT x x x x x  
81 PROTOCOL: ALT-CELLULAR x x x x x  
84 CONNECT 33600 1 x x x x Note 3
91 CONNECT 31200 1 x x x x Note 3
150 CARRIER 32000 x x x x x Note 4
151 CARRIER 34000 x x x x x Note 4
152 CARRIER 36000 x x x x x Note 4
153 CARRIER 38000 x x x x x Note 4
154 CARRIER 40000 x x x x x Note 4
155 CARRIER 42000 x x x x x Note 4
156 CARRIER 44000 x x x x x Note 4
157 CARRIER 46000 x x x x x Note 4
158 CARRIER 48000 x x x x x Note 4
159 CARRIER 50000 x x x x x Note 4
160 CARRIER 52000 x x x x x Note 4
161 CARRIER 54000 x x x x x Note 4
162 CARRIER 56000 x x x x x Note 4
165 CONNECT 32000 x x x x x Note 4
166 CONNECT 34000 x x x x x Note 4
167 CONNECT 36000 x x x x x Note 4
168 CONNECT 38000 x x x x x Note 4
169 CONNECT 40000 x x x x x Note 4
170 CONNECT 42000 x x x x x Note 4
171 CONNECT 44000 x x x x x Note 4
172 CONNECT 46000 x x x x x Note 4
173 CONNECT 48000 x x x x x Note 4
174 CONNECT 50000 x x x x x Note 4
175 CONNECT 52000 x x x x x Note 4
176 CONNECT 54000 x x x x x Note 4
177 CONNECT 56000 x x x x x Note 4
178 CONNECT 230400 x x x x x Note 4
180 CONNECT 28000 x x x x x Note 4
181 CONNECT 29333 x x x x x Note 4
182 CONNECT 30667 x x x x x Note 4
183 CONNECT 33333 x x x x x Note 4
184 CONNECT 34667 x x x x x Note 4
185 CONNECT 37333 x x x x x Note 4
186 CONNECT 38667 x x x x x Note 4
187 CONNECT 41333 x x x x x Note 4
188 CONNECT 42667 x x x x x Note 4
189 CONNECT 45333 x x x x x Note 4
190 CONNECT 46667 x x x x x Note 4
191 CONNECT 49333 x x x x x Note 4
192 CONNECT 50667 x x x x x Note 4
193 CONNECT 53333 x x x x x Note 4
194 CONNECT 54667 x x x x x Note 4
+F4 +FCERROR x x x x x  
Notes
  • 1. An 'x' in a column indicates that the message (either the long form if verbose, or the value only for short form) will be generated when that particular value of 'n' (shown at the top of the column) has been selected by the use of ATXn. If the column is blank, then no message will be generated for that x option. A numeral indicates which less explicit message (verbose or short form) will be output for that X option.
  • 2. RC288 and higher rate modems.
  • 3. RC336 and higher rate modems.
  • 4. RC56 modems.


S-REGISTERS

This section defines the purpose of the modem registers, and sequentially
lists the registers and describes their functions. These registers affect
various operating characteristics and allow you to obtain information
about the modem, as well as test the modem. The valid ranges for the
registers are also included.

READING A REGISTER VALUE

You can inquire about the current value of these  registers with the  S?
command. To read the current value of a register, type:

AT Sn? [ENTER],

where n is a register number.

To read the register values of S0 and S7, type

AT S0? S7? [ENTER].

The modem will display the first register value, a carriage
return, the next register value, a carriage return, and OK or 0.

CHANGING A REGISTER VALUE

To change a register value, use the Sn command (ATSn=v), where n
is a register number and v is the new value you want to assign to
the register. Type:

AT S0=1 [ENTER]

to have the modem automatically answer on the firt ring.

S-Registers
Register
Function
0
Rings to auto-answer
Set the number of rings required before the modem answers. 0 setting disables auto-answer.
Range: 0 - 255 rings
Default: 0 (auto-answer disabled) (May be saved in NV Ram with the &Wn command.)
1
Ring counter
Count the number of rings before the modem answers.
Range: 0 - 255 rings
Default: 0 
2
Escape character
Define the character used for the three-character escape code sequence. 0 setting disables the escape code character.
Range: 0 - 255
Default: 43 (+) (May be saved in NV Ram with the &Wn command.)
3
Carriage return character
Define the character for carriage return
Range: 0 - 127
Default: 13 (carriage return)
4
Line feed character
Define the character for line feed 
Range: 0 - 127 
Default: 10 (line feed) 
5
Backspace character
Define the character for backspace
Range: 0 - 255
Default: 8 (backspace)
6
Wait before dialing
Set the length of time to pause after off hook before dial.
Range: 2 - 255 seconds
Default: 2 seconds (May be saved in NV Ram with the &Wn command.)
7
Wait for carrier after dial
Set the length of time that the modem waits for a carrier from the remote modem before hanging up.
Range: 1 - 255 seconds
Default: 50 seconds (May be saved in NV Ram with the &Wn command.)
8
Pause time for dial delay
Set the length of time to pause for the pause dial modifier ",".
Range: 0 - 255 seconds
Default: 2 seconds (May be saved in NV Ram with the &Wn command.)
9
Carrier detect response time
Define the length of time a signal is detected and qualified as a carrier.
Range: 1 - 255 tenths of a second
Default: 6 (0.6 seconds) (May be saved in NV Ram with the &Wn command.)
10
Lost carrier hang up delay
S10 sets the length of time, in tenths of a second, that the modem waits before hanging up after a loss of carrier. This allows

for a temporary carrier loss without causing the local modem to disconnect. When register S10 is set to 255, the modem 
functions as if a carrier is always present. 
The actual interval the modem waits before disconnecting is the value in register S10 minus the value in register S9. 
Therefore, the S10 value must be greater than the S9 value or else the modem disconnects before it recognizes the carrier. 
Range: 1 - 255 tenths of a second
Default: 14 (1.4 seconds) (May be saved in NV Ram with the &Wn command.)
Note: For Call Waiting detection, if the modem is set to US country code and S10 >=16, then the modem will detect the Call

Waiting tone and hang-up the line. If S10 <16, the modem will not detect Call Waiting tone.
11
DTMF speed control
Set the length of tone and the time between tones for the tone dialing.
Range: 50 - 255 milliseconds
Default: 95 milliseconds (May be saved in NV Ram with the &Wn command.)
12
Escape Prompt Delay (EPD) timer
Set the time from detection of the last character of the three character escape sequence until the "OK" is returned to the DTE
Range: 0 - 255 fiftieths of a second
Default: 50 (1 second) (May be saved in NV Ram with the &Wn command.)
29
Flash Dial Modifier Time
Sets the length of time, in units of 10 ms, that the modem will go on-hook when it encounters the flash (!) dial modifier in the dial string.
Range: 0 - 255 hundredths of a second

Default: 70 (0.7 second)