SocketModemꢀ
Embedded Modem
MT2456SMI–22
Serial Interface
Developer’s Guide
Contents
Physical Dimensions..................................................................................................................................................6
Chapter 4 - V.22bis Commands, S-Registers, and Result Codes............................................................................10
V.22bis DTE/DCE-Modem Interface commands......................................................................................................15
V.22bis Call Control Commands..............................................................................................................................21
V.22bis Line Side Device Commands......................................................................................................................34
V.22bis S-Parameters..............................................................................................................................................35
Compliance..............................................................................................................................................................52
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
3
Chapter 1 – Product Description and Specifications
Chapter 1 – Product Description and
Specifications
The Multi-Tech SocketModem supports analog data modem operation with V.22bis Fast Connect, V.42bis data
compression, and V.80 synchronous access mode. The SocketModem is a space-efficient (1" × 2.5"), embedded
modem that is ready-to-integrate into your applications; therefore, dramatically reducing development time and
costs for system designers. The SocketModem also complies with telecom requirements globally and can be
shipped worldwide.
This guide provides the information needed to effectively integrate the SocketModem into your equipment. It also
includes the AT commands for the configuration and control of a data modem and the result codes that the
modem issues in response to the commands.
Product Description
The MT2456SMI SocketModem is a standard 64-pin modem used for integrating data communications. It is a
single-port 5V or 3.3V modem that integrates a modem controller, DSP, and DAA in a 1" x 2.5" form factor and
communicates to a host controller via an asynchronous serial interface.
A SocketModem kit is available. It includes one development board with an RS-232 DB-25 connector, wall power
adapter, RJ-11 jack, and RS-232 cable.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
4
Chapter 1 – Product Description and Specifications
Technical Specifications
The SocketModem meets the following specifications:
Client-to-Server Data Rates
Client-to-Client Data Rates
Data Format
V.22 bis
2400, 1200, 0-300 bps
Serial, asynchronous
Modem Compatibility
Error Correction
V.22bis, V.22; Bell 212A and 103/113; ITU-T V.21 & V.23
ITU-T V.42 (LAP-M or MNP 2–4)
Data Compression
Speed Conversion
ITU-T V.42bis
Serial port data rates adjustable to 300, 1200, 2400, 4800, 9600, 19,200, 38,400,
57,600, and 115,200
Modes of Operation
Full duplex over dial-up lines; data mode, command mode, and online command
mode
Flow Control
XON/XOFF (software), RTS/CTS (hardware)
50 characters
Command Buffer
Transmit Level
Frequency Stability
Receiver Sensitivity
Interface
–12 dBm (varies by country setting)
±0.01%
–43 dBm under worst-case conditions
Serial ITU-T V.24 logical interface
Local analog loop
Diagnostics
Weight
0.02 Kg. (0.04 lb.)
Dimensions
1.045" × 2.541" × 0.680" (2.7 x 6.5 x 1.8 cm)
Power Consumption
Operating Voltage
Operational Temperature
Typical: 70 mA (.235 W @ 3.3V DC); Maximum: 80 mA (.264 W @ 3.6V DC)
Typical: 3.3V DC +/- 5%; Absolute Maximum Supply Voltage: 3.7 V DC
0 to +70° C ambient under closed conditions; humidity range 20% to 90% (non-
condensing)
Storage Temperature
Intelligent Features
-10° to +85° C
TIA-602 command compatible
V.22bis fast connect
Supports V.80
Supports Fast POS 9600
Line polarity reversal detection
Line current loss detection
Line-in-use detection during on-hook operation
Extension pickup detection
Call waiting detection
Caller ID (US configuration only)
DTMF detection
autodial, redial
pulse or tone dial
auto answer
call status display
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
5
Chapter 2 ꢀ Mechanical Specifications
Pin Configurations
The MT2456SMI SocketModem with a serial interface use a 16-pin interface to provide an on-board DAA with tip
and ring connections, audio circuit for call-progress monitoring and serial interface via logic level signals.
Figure 2–2. Serial SocketModem Pins
Pin Descriptions
Pin
#
1
Signal
Name
Tip
I/O
Type
I/O
Description
Tip Signal from Telco. Tip connection to the phone line (RJ11 Pin 3).
SocketModem is Tip/Ring is polarity insensitive.
Ring Signal from Telco. Ring connection to the phone line (RJ11 Pin 4).
SocketModem is Tip/Ring is polarity insensitive.
2
Ring
I/O
I
Modem Reset (with weak pull-up). The active low –RESET input resets the
SocketModem logic and returns the AT command set to the original factory
default values or to "stored values" in NVRAM. –RESET is tied to VCC
through a 250 ms time constant circuit for "Power-on-Reset" functionality. The
modem is ready to accept commands within 6.5 seconds of power-on or reset.
Reset must be asserted for a minimum of 300 ns.
24
–RESET
Ground.
26
29
30
31
32
33
34
DGND
DCDIND
RXIND
DTRIND
TXIND
–RTS
DCD LED Indicator.
RXD LED Indicator.
DTR LED Indicator.
TXD LED Indicator.
Request to Send. RTS signal is used for hardware flow control.
I
Received Data. Used to send data received from the telephone line and also
modem responses to the DTE. Modem response take priority over incoming
data. When no data is transmitted, the signal is held in mark condition.
Transmit Data. The DTE uses this line to send data to the modem for
transmission over the telephone line or to transmit commands to the modem.
The DTE should hold this circuit in the mark state when no data is being
transmitted or during intervals between characters.
–RXD
O
35
–TXD
I
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
7
Chapter 2 ꢀ Mechanical Specifications
Ring Indicate. –RI output ON (low) indicates the presence of an ON segment
of a ring signal on the telephone line. The modem will not go off-hook when –
RI is active; the modem waits for –RI to go inactive before going off-hook.
Data Set Ready. -DSR indicates modem status to the DTE. –DSR OFF
(high) indicates that the DTE is to disregard all signals appearing on the
interchange circuits except Ring Indicator (–RI). It reflects the status of the
local data set, and does not indicate an actual link with any remote data
equipment.
36
37
–RI
O
O
–DSR
Clear To Send. –CTS is controlled by the modem to indicate whether or not
the modem is ready to transmit data. –CTS ON, indicates to the DTE that
signals presented on TXD will be transmitted to the telephone line. –CTS OFF
indicates to the DTE that it should not transfer data across the interface on
TXD.
38
–CTS
O
Data Carrier Detect. –DCD output is ON (low) when a carrier is detected on
the telephone line or OFF (high) when carrier is not detected.
Data Terminal Ready (Active Low). The –DTR input is turned ON (low) by
the DTE when the DTE is ready to transmit or receive data. –DTR ON
prepares the modem to be connected to the telephone line, and, once
connected, maintains the connection. –DTR OFF places the modem in the
disconnect state.
39
40
–DCD
–DTR
O
I
Ground.
41
61
63
DGND
VCC
3.3V DC Power.
Analog Ground. Analog ground is tied common with DGND on the
SocketModem. To minimize potential ground noise issues, connect audio
circuit return to AGND.
AGND
Speaker Output. SPKR is a single ended-output. SPKR is tied directly to the
CODEC. One side of a differential AC output coupled through a 6.8K ohm
resistor and capacitor.
64
SPKR
The call progress speaker interface signal is:
Digital speaker output (DSPKOUT); output
DSPKOUT is a square wave output in data mode used for call progress or
carrier monitoring. This output can be optionally connected to a low-cost on-
board speaker, e.g., a sounducer, or to an analog speaker circuit.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
8
Chapter 3 ꢀ Electrical Characteristics
Chapter 3 – Electrical Characteristics
3.3V and 5V Serial SocketModem
3.3V DC Characteristics (TA = 0°C to 70°C; VDD = 3.3 V ± 0.3 V) VDDMAX = 3.6 V
5V DC Characteristics (TA = 0°C to 50°C; VDD = 5 V ± 0.25 V) VDDMAX = 5.25 V
Input High
Input Low
Inputs
–DTR (40), –TXD (35), –RTS (33), –RESET (24)
Min 2.0 V
Max 0.8 V
Outputs
Output High
Output Low
–DCD (39), –CTS (38), –DSR (37), –RI (36), –RXD (34)
Min 2.4 V
Max 0.4 V
2mA, Z
= 120 Ω
INT
50pF
Digital Input Capacitance
Handling Precautions
All electronic devices should be handled with certain precautions to avoid damage due to the accumulation of
static charge. Although input protection circuitry has been incorporated into the devices to minimize the effect of
this static buildup, proper precautions should be taken to avoid exposure to electrostatic discharge during
handling and mounting.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
9
Chapter 4 - V.22bis Commands
Chapter 4 - V.22bis Commands, S-
Registers, and Result Codes
The V.22bis Commands are covered in the following order in this chapter:
Generic Modem Control Commands
Z
Soft Reset and Restore Profile
Caller ID
Report Retrieved Called ID
Operating Mode - Error Correction
Identification
+VCID
+VRID
\N
I
+GCI
&F
&T
Country of Installation
Restore Factory Configuration (Profile)
Local Analog Loopback Test
Load to Internal RAM
**
DTE/DCE Commands
E
Echo
Q
Quiet Result Codes
V
Result Code Form
W
X
Connect Message Control
Extended Result Codes (& Call Progress Information)
RLSD Option
DTR Option
Flow Control
&C
&D
&K
&R
\G
RTS/CTS Option
Modem-to-Modem Flow Control (XON/XOFF)
DTE-Modem Local Flow Control
In Band Commands
+IFC
+IBC
Call Control Commands
D
Dial
T
P
Set Tone Dial (Default)
Set Pulse Dial
A
Answer
H
O
L
M
&G
&P
&V
%L
%Q
*B
Disconnect (Hang Up)
Return to On-line Data Mode
Monitor Speaker Volume
Monitor Speaker Mode Control
Select Guard Tone
Select Pulse Dial Make/Break Ratio
Display Current Configuration and Stored Profiles
Report Line Signal Level
Report Line Signal Quality
Display Blacklisted Numbers
Display Delayed Numbers
Set Telephony Extension
Call Waiting Enable
*D
-STE
+PCW
+VDR
Distinctive Ring
Modulation Control Commands
+MS
%E
B
Modulation Selection
Enable/Disable Line Quality Monitor
ITU-T or Bell
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
10
Chapter 4 - V.22bis Commands
Error Control and Data Compression Commands
+ESR
\B
\K
Select Repeat
Transmit Break to Remote
Break Control
Synchronous Access Mode Commands
+ESA
+ITF
Configure Synchronous Access Submode
Transmit Flow Control Thresholds
Fast Connect Command
$F
Fast Connect Control
Line Side Device Commands
-TTE
-TRV
Threshold Adjustments for Telephony Extension
Tip and Ring Voltage Measurement
A Note About Compatibility Commands
You may notice that some commands are available but do not support any function. These commands exist for
compatibility purposes only. If you enter these commands, you may receive an OK result; however, no changes
are made to the configuration or control of the modem. Examples of these commands are:
Y, &S, &V1, +VDT, and \A,
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
11
Chapter 4 - V.22bis Commands
V.22bis Generic Modem Control
Commands
Z
Soft Reset and Restore Profile
This command causes the modem to perform a soft reset and restore (recall) the factory default configuration
(profile). If no <value> is specified, zero is assumed.
Syntax
Z<value>
Defined Values
<value> Decimal number corresponding to the selected profile.
0
Soft reset and restore stored profile.
1
Same as 0; allowed for compatibility.
Result Codes
OK <value> = 0 or 1
ERROR Otherwise
+VCID Caller ID (CID)
This command controls the reporting and presentation of data associated with the Caller ID services in the Incoming
Call Line ID (ICLID) data format for the next call.
Syntax +VCID=<pmode>
Defined Values
<pmode> Decimal number corresponding to the selected option.
0
1
Disable Caller ID reporting. (Default).
Enables Caller ID with formatted presentation to the DTE. The modem presents the data items in a
<Tag><Value> pair format. The expected pairs are date, time, name, and caller code (telephone number).
Enables Caller ID with unformatted presentation to the DTE.
2
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: (0-2)
+VRID Report Retrieved Caller ID (CID)
This command reports the data associated with the Caller ID services in the Incoming Call Line ID (ICLID) data
format for the last received call.
Syntax +VRID=<pmode>
Defined Values
<pmode> Decimal number corresponding to the selected option.
0
Reports Caller ID with formatted presentation to the DTE. The modem presents the data items in a <Tag><Value>
pair format. The expected pairs are date, time, name, and caller code (telephone number).
Reports Caller ID with unformatted presentation to the DTE.
1
Reporting Supported Range of Parameter Values
Command: +VRID=?
Response: +VRID: (<pmode> range)
Example: +VRID: (0,1)
\N
Operating Mode
This command controls the preferred error-correcting mode to be negotiated in a subsequent data connection.
Syntax \N<mode>
Defined Values
<mode> Decimal number which corresponds to the selected mode.
0
1
Selects normal speed buffered mode (disables error-correction mode). (Forces &Q6.)
Serial interface selected - Selects direct mode and is equivalent to &M0, &Q0 mode of operation. (Forces &Q0.)
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
12
Chapter 4 - V.22bis Commands
2
Selects reliable (error-correction) mode. The modem will first attempt a LAPM connection and then an MNP
connection. Failure to make a reliable connection results in the modem hanging up. (Forces &Q5, S36=4, and
S48=7.)
3
4
5
Selects auto-reliable mode. This operates the same as \N2 except failure to make a reliable connection results in
the modem falling back to the speed buffered normal mode. (Forces &Q5, S36=7, and S48=7.)
Selects LAPM error-correction mode. Failure to make an LAPM error-correction connection results in the modem
hanging up. (Forces &Q5 and S48=0.)
Selects MNP error-correction mode. Failure to make an MNP error-correction connection results in the modem
hanging up. (Forces &Q5, S36=4, and S48=128.)
Result Codes OK <mode> = 0 to 5
ERROR Otherwise
I
Identification
This command causes the modem to reports the requested result according to the command parameter.
Syntax I<value>
Defined Values
<value> Decimal number corresponding to the selected information.
0
1
Reports product code, e.g., “2400”.
Reports the least significant byte of the stored checksum in decimal. Reports 255 if the prestored checksum value
is FFh.
2
3
Reports "OK".
Reports identification codes.
RevisionName = masked firmware code version. Example: Patton Modulation = V.22bis
Example:
Patton-V22B
4
Reports OEM defined identifier string in either Hayes-compatible binary format (default), e.g.: a007040284C6002F
bC60000000r10051111510120003000111170000000
Reports Country Code parameter (see +GCI).
Reports “OK”.
5
6
7
Reports “OK”.
Result Codes OK <value> = 0 - 7
ERROR Otherwise
+GCI
Country of Installation
This extended syntax command selects and indicates the country of installation for the modem. This parameter
selects the settings for any operational parameters that need to be adjusted for national regulations or telephone
networks. Additional country profiles can be uploaded and existing ones can be modified by minor firmware upgrade
via SRAM patch.
Syntax +GCI=<country_code>
Country Code
Japan 00
Argentina 01
Taiwan 02
New Zealand 03
Singapore 04
Australia 09
Euro/NAM B5
International 99
Malaysia 6C
South Africa 9F
Default If the modem is specified for use in only one country, that country code is the default. Otherwise, the default
is defined by the OEM. Factory default is B5 (United States).
Reporting Current or Selected Values
Command: +GCI?
Response: +GCI: <current country_code>
Example: +GCI: B5 The modem is set for U.S.
Reporting Supported Range of Parameter Values
Command: +GCI=?
Response: +GCI: (<country_code>[,<country_code>[,<country_code].......]]
Example: +GCI: (00,B4,B5) The modem can be set for Japan, United Kingdom, or the United States.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
13
Chapter 4 - V.22bis Commands
&F
Restore Factory Configuration (Profile)
The modem loads the factory default configuration (profile). The factory defaults are identified for each command and
in the S-Parameter descriptions. A configuration (profile) consists of a subset of S-Parameters.
Syntax &F[<value>]
Defined Values
<value> Decimal number corresponding to the selected configuration.
0
1
Restore factory configuration 0.
Same as 0; allowed for compatibility.
Result Codes OK
ERROR If the modem is connected
&T
Local Analog Loopback Test
The modem will perform the local analog loopback test if &T1 is selected. The test can be run only when in an
asynchronous operation in non-error-correction mode (normal), e.g., AT&Q6. To terminate the test in progress, the
escape sequence must be entered first.
Syntax
&T[<value>]
Defined Values
<value> Decimal number corresponding to the selected option.
0
1
Terminates test in progress. Clears S16.
Initiates local analog loopback, V.54 Loop 3. Sets S16 bit 0. If a connection exists when this command is issued,
the modem hangs up. The CONNECT XXXX message is displayed upon the start of the test.
**
Load to Internal RAM
This command allows the internal SRAM to be loaded with patch code for minor firmware upgrade including country
profile customization. This process transfers the S37 file from the host computer to the modem. The data transfer is
done via an ASCII transfer. A successful upload can be verified by invoking ATI3 and/or ATI4 command depending
on which of the two were modified. The patch is erased when the power is turned off.
Procedure
1. Configure the communications application program for a DTE rate of 115200 bps.
Check the modem for response by typing AT.
2. Issue AT** command to initiate the download process. The following message appears:
Download initiated.
3. Send the patch code (e.g., patv00028.s37). The following message appears on successful upload:
Modem Firmware Successfully Loaded
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
14
Chapter 4 - V.22bis Commands
V.22bis DTE/DCE-Modem Interface
commands
The parameters defined in this section control the operation of the interface between the DTE/DCE and modem.
E
Command Echo
The modem enables or disables the echo of characters to the DTE. The valid parameter value is written to S14 bit 1.
Syntax E<value>
Defined Values
<value> Decimal number corresponding to the option.
0
1
Disables command echo.
Enables command echo. (Default)
Result Codes
OK <value> = 0 or 1
ERROR Otherwise
Q
Quiet Result Codes Control
The command enables or disables the sending of result codes to the DTE. The parameter value, if valid, is written to
S14 bit 2.
Syntax Q<value>
Defined Values
<value> Decimal number corresponding to the option.
0
1
Enables result codes to the DTE. (Default)
Disables result codes to the DTE.
Result Codes
OK <value>= 0 or 1
ERROR Otherwise
V
Result Code Form
This command selects the sending of short-form or long-form result codes to the DTE. The parameter, if valid, is
written to S14 bit 3.
Syntax V<value>
Defined Values
<value> Decimal number corresponding to the selected option.
0
1
Enables short-form (terse) result codes. Line feed is not issued before a short-form result code.
Enables long-form (verbose) result codes. (Default)
Result Codes
OK <value>= 0 or 1
ERROR Otherwise
W
Connect Message Control
This command, in conjunction with S95 bits 0, 2, and 3, (bits 2 and 3 can be written directly by the host), control the
format of CONNECT messages. The actual result code messages reported reflect the W command setting and the
S95 bit settings.
The W parameter value, if valid, is written to S31 bits 2 and 3.
Syntax W<value>
Defined Values
<value> Decimal number corresponding to the selected option.
0
1
2
Upon connection, the modem reports only the DTE speed (e.g., CONNECT 19200). Subsequent responses are
disabled. (Default)
Upon connection, the modem reports the modulation, line speed, the error correction protocol, and the DTE
speed, respectively. Subsequent responses are disabled.
Upon connection, the modem reports the DCE speed (e.g., CONNECT 2400). Subsequent responses are
disabled.
Result Codes
OK <value> = 0, 1, or 2
ERROR Otherwise
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
15
Chapter 4 - V.22bis Commands
X
Extended Result Codes
This command selects the subset of the result code messages used by the modem to inform the DTE of the results of
commands. Blind dialing is enabled or disabled by country parameters. If the user wishes to enforce dial tone
detection, a "W" can be placed in the dial string (see D command). The information below is based upon the default
implementation of the X results table.
Syntax X<value>
Defined Values
<value> Decimal number corresponding to the selected option.
0
Disables reporting of busy tones unless forced otherwise by country requirements; send only OK, CONNECT,
RING, NO CARRIER, ERROR, and NO ANSWER result codes. Blind dialing is enabled/disabled by country
parameters. If busy tone detection is enforced and busy tone is detected, NO CARRIER will be reported. If dial
tone detection is enforced or selected and dial tone is not detected, NO CARRIER will be reported instead of NO
DIAL TONE. The value 000b is written to S22 bits 6, 5, and 4, respectively.
1
Disables reporting of busy tones unless forced otherwise by country requirements; send only OK, CONNECT,
RING, NO CARRIER, ERROR, NO ANSWER, and CONNECT XXXX (XXXX = rate). Blind dialing
enabled/disabled by country parameters. If busy tone detection is enforced and busy tone is detected, NO
CARRIER will be reported instead of BUSY. If dial tone detection is enforced or selected and dial tone is not
detected, NO CARRIER will be reported instead of NO DIAL TONE. The value 100b is written to S22 bits 6, 5,
and 4, respectively.
2
Disables reporting of busy tones unless forced otherwise by country requirements; send only OK, CONNECT,
RING, NO CARRIER, ERROR, NO DIAL TONE, NO ANSWER, and CONNECT XXXX. If busy tone detection is
enforced and busy tone is detected, NO CARRIER will be reported instead of BUSY. If dial tone detection is
enforced or selected and dial tone is not detected, NO DIAL TONE will be reported instead of NO CARRIER. The
value 101b is written to S22 bits 6, 5, and 4, respectively.
3
4
Enables reporting of busy tones; send only OK, CONNECT, RING, NO CARRIER, ERROR, NO ANSWER, and
CONNECT XXXX. Blind dialing is enabled/disabled by country parameters. If dial tone detection is enforced and
dial tone is not detected, NO CARRIER will be reported. The value 110b is written to S22 bits 6, 5, and 4,
respectively.
Enables reporting of busy tones; send all messages. The value 111b is written to S22 bits 6, 5, and 4,
respectively. (Default)
Result Codes
OK <value> = 0 to 4
ERROR Otherwise
Table of Result Codes
n Value in ATXn Command
Short Form
Long Form
0
X
X
X
X
X
1
3
3
X
1
1
1
1
1
1
1
1
1
1
1
1
1
4
4
X
X
1
2
3
4
0
1
2
3
4
5
6
7
OK
CONNECT
RING
NO CARRIER
ERROR
CONNECT 1200
NO DIAL TONE
BUSY
X
X
X
X
X
X
3
X
X
X
X
X
X
X
3
X
X
X
X
X
X
X
X
X
X
X
X
X
X
4
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
4
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
3
8
9
NO ANSWER
X
X
X
X
X
X
X
X
X
X
X
X
X
X
4
CONNECT 600
CONNECT 2400
CONNECT 4800
CONNECT 9600
CONNECT 7200
CONNECT 12000
CONNECT 14400
CONNECT 19200
CONNECT 38400
CONNECT 57600
CONNECT 115200
CONNECT 75TX/1200RX
CONNECT 1200TX/75RX
DELAYED
10
11
12
13
14
15
16
17
18
19
22
23
24
32
40
41
BLACKLISTED
CARRIER 300
CARRIER 1200/75
4
X
X
4
X
X
4
X
X
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
16
Chapter 4 - V.22bis Commands
n Value in ATXn Command
Short Form
Long Form
0
1
2
3
4
42
46
47
67
70
83
85
86
CARRIER 75/1200
CARRIER 1200
CARRIER 2400
PROTOCOL: V42
PROTOCOL: NONE
LINE IN USE
OFF-HOOK INTRUSION
LINE REVERSAL DETECTED
NO LINE
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
87
Note:
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.
&C
RLSD Option
The modem controls the RLSD output in accordance with the parameter supplied. The parameter value, if valid, is
written to S21 bit 5.
Syntax &C<value>
Defined Values
<value> Decimal number corresponding to the selected option.
0
1
RLSD remains ON at all times.
RLSD follows the state of the carrier. (Default)
Result Codes
OK 0 or 1
ERROR Otherwise
&D
DTR Option
This command interprets the ON to OFF transition of the DTR signal from the DTE in accordance with the parameter
supplied. The parameter value, if valid, is written to S21 bits 3 and 4. Also, see S25.
Syntax &D<value>
Defined Values
<value> Decimal number corresponding to the selected option.
0
DTR drop is interpreted according to the current &Qn setting as follows:
&Q0, &Q5, &Q6: DTR is ignored (assumed ON). Allows operation with DTEs, which do not provide DTR.
&Q1: DTR drop causes the modem to hang up. Auto-answer is not affected.
&Q2, &Q3: DTR drop causes the modem to hang up. Auto-answer is inhibited.
DTR drop is interpreted according to the current &Qn setting as follows:
1
&Q0, &Q1, &Q5, &Q6: DTR drop is interpreted by the modem as if the asynchronous escape sequence had been
entered. The modem returns to asynchronous command state without disconnecting.
&Q2, &Q3: DTR drop causes the modem to hang up. Auto-answer is inhibited.
DTR drop is interpreted according to the current &Qn setting as follows:
&Q0 through &Q6: DTR drop causes the modem to hang up. Auto-answer is inhibited. (Default)
DTR drop is interpreted according to the current &Qn setting as follows:
2
3
&Q0, &Q1, &Q5, &Q6: DTR drop causes the modem to perform a soft reset as if the Z command were received.
&Q2, &Q3: DTR drop causes the modem to hang up. Auto-answer is inhibited.
&K
Flow Control
This command defines the DTE/DCE (terminal/modem) flow control mechanism. The parameter value, if valid, is
written to S39 bits 0, 1, and 2.
Syntax &K<value>
Defined Values
<value> Decimal number corresponding to the selected option.
0
3
4
5
Disables flow control.
Enables RTS/CTS flow control. (Default for data modem modes.)
Enables XON/XOFF flow control.
Enables transparent XON/XOFF flow control.
Result Codes
OK <value> = 0, 3, 4, or 5
ERROR Otherwise
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
17
Chapter 4 - V.22bis Commands
&R
RTS/CTS Option
This selects how the modem controls CTS. CTS operation is modified if hardware flow control is selected (see &K
command). The parameter value, if valid, is written to S21 bit 2.
Syntax &R<value>
Defined Values
<value> Decimal number corresponding to the selected option.
0
In sync mode, CTS tracks the state of RTS; the RTS-to-CTS delay is defined by S26. In async mode, CTS is
normally ON and will turn OFF only if required by flow control.
1
In sync mode, CTS is always ON and RTS transitions are ignored. In async mode, CTS is normally ON and will
turn OFF only if required by flow control.
Result Codes
OK <value> = 0 or 1
ERROR Otherwise
\G
Modem-to-Modem Flow Control (XON/XOFF)
The modem enables or disables the generation or recognition of modem-to-modem XON/XOFF flow control
according to the parameter supplied. The parameter value, if valid, is written to S41 bit 3.
Due to the buffering system used in the modem, modem-to-modem flow control is normally disabled.
Syntax \G<value>
Defined Values
<value> Decimal number corresponding to the selected option.
0
Disables modem-to-modem XON/XOFF flow control. (Default.)
1
Enables modem-to-modem XON/XOFF flow control.
Result Codes
OK <value> = 0 or 1
ERROR Otherwise
+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
1
None.
XON/XOFF on transmitted data (XON/XOFF on transmit data); do not pass XON/XOFF characters to the
remote modem.
2
3
Circuit 133 (Ready for Receiving). (Default)
DC1/DC3 on circuit 103 (Transmitted Data) with DC1/DC3 characters being passed through to the remote
DCE in addition to being acted upon for local flow control
<DTE_by_modem> Specifies method to be used by the modem to control the flow of transmitted data from the DTE.
0
1
2
None.
XON/XOFF on received data.
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)
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
18
Chapter 4 - V.22bis Commands
+IBC
In Band Commands
This command provides a mechanism by which an in-band secondary channel may be implemented. This in-band
secondary channel can be utilized to transparently exchange commands and responses to/from the modem during a
data connection. This is an alternative approach to using the +++ escape sequence. The +IBC command also
provides a mechanism to exchange V.24 signaling via the secondary channel. The primary reason the In Band
Channel is implemented is to retrieve Caller ID type II information. The supported In Band Channel command is
compatible with the ITU-T V.80 standard but is not a full V.80 implementation. TheV.80 protocol supported is
described below. Portions of the V.80 protocol not described are not supported. Please refer Section 7 of the ITU-T
V.80 standard for more details..
Syntax +IBC=<IB>,<105>,<106>,<107>,<108>,<109>,<110>,<125>,<132>,<133>,<135>, <142>,<hook>
Defined Values
<IB>
Enables or disables in-band control sequence.
0
1
2
Disable in-band control sequences.
Enable 7-bit in-band control sequences. Ignore eighth bit.
Enable 8-bit in-band control sequences.
<105> Enables or disables V.24 circuit type 105: RTS (Ready to Send).
0
1
Disable in-band reporting for this circuit.
Enable in-band reporting for this circuit.
<106> Enables or disables the circuit type 106: CTS (Clear to Send).
0
2
Disable in-band reporting for this circuit.
Enable in-band reporting for this circuit.
<125> Enables or disables the circuit type 125: RI (Ring Indicate).
0
1
Disable in-band reporting for this circuit.
Enable in-band reporting for this circuit.
<other> Not supported; leave ‘0’ for the unsupported circuit types.
<hook> Not supported; leave ‘0’.
Reporting Current or Selected Values
Command: +IBC?
Response: +IBC=<value>.<value>,<value>,0,0,0,0,<value>,0,0,0,0,0
Example: +IBC=0,0,0,0,0,0,0,0,0,0,0,0,0
Reporting Supported Range of Parameter Values
Command: +IBC=?
Response: +IBC: (0-2),(0-1),(0-1),0,0,0,0,(0-1),0,0,0,0,0)
Entering and Exiting In Band Active State
In Band Command mode will be active only when a modem connection has been made and DCD is on and the
modem is not in command mode. Upon a data connection before the connect message is sent, an In Band message
will be sent to the DTE to notify that all further data will be EM shielded and should be filtered. Any other time (i.e.,
command mode or idle mode) the DTE should allow all user data to be in pass-through mode in which the data is
unfiltered.
The DTE will receive one of the following active messages:
EM<60h><26h><62h>+IBC:1 to indicate In Band is active and the server is V.92
EM<60h><26h><62h>+IBC:2 to indicate In Band is active and the server is non-V.92
Upon Hang up or escape to command mode, the In Band command mode will end and the DTE should stop filtering
EM data and return to pass-through mode.
The DTE will receive the following inactive In Band message:
EM<60h><26h><62h>+IBC:0 to indicate In Band is inactive
EM Shielding Data
When in-band control sequences are enabled, the DTE and the modem must shield and filter data containing EM. In
V.80, in-band data is shielded from normal data by an EM character represented by a <19h> or <99h>. If the DTE’s
data contains an EM, an additional character is inserted.
For example, sending <19h> from the DTE to the modem requires inserting a <singleEM> or <5Ch> into the data
stream (e.g., <19h><5Ch>). The modem encodes this as one <19h> in the user data. On the other hand, sending
<19h> from the modem to the DTE requires inserting a <singleEM> or <7Ch>. Please refer to the V.80 standard for
more information.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
19
Chapter 4 - V.22bis Commands
Table of Supported V.80 Commands
Command
Hex Codes
Description
Supported V.80 DTE-to-DCE Commands
<extend0> <length>
<control> <rest of command>
<105off>
<40h>
<42h>
<42h>
<43h>
<58h>
<59h>
<5Ch>
<5Dh>
<5Eh>
The DCE decodes this as a sequence of 3 + (<length>-1Fh).
Circuit 105 is OFF.
Circuit 105 is ON.
<105on>
<singleEMp>
<doubleEMp>
<singleEM>
<doubleEM>
<poll>
The DCE decodes this as one <99h> in user data.
The DCE decodes this as <99h><99h> in user data.
The DCE decodes this as on <19h> in user data.
The DCE decodes this as <19h><19h> in user data.
The DCE decodes this command and deliver a set of status
commands, one for each circuit enabled.
Supported V.80 DCE-to-DTE Commands
<extend0> <length>
<status> <rest of command>
<106off>
<106on>
<125off>
<60h>
<62h>
<62h>
<63h>
<6Ah>
<6Bh>
<76h>
<77h>
<7Ch>
<7Dh>
The DCE decodes this as a sequence of 3 + (<length>-1Fh).
Circuit 106 is OFF.
Circuit 106 is ON.
Circuit 125 is OFF.
Circuit 125 is ON.
The DCE encodes this as one <99h> in user data.
The DCE encodes this as <99h><99h> in user data.
The DCE encodes this as on <19h> in user data.
The DCE encodes this as <19h><19h> in user data.
<125on>
<singleEMp>
<doubleEMp>
<singleEM>
<doubleEM>
In Band Processing of AT Commands
When in-band control sequences are enabled, the modem responds to EM shielded AT commands via the extend-0
CONTROL sequence. This command may be used to transmit any AT commands to the modem as follows:
EM <extend-0> <length> <CONTROL> <AT Command without AT and trailing carriage return>
Upon receipt of an in-band command, the modem responds with the extend-0 STATUS REPORT sequence. This
sequence will contain the response to the AT command issued via the CONTROL sequence with the trailing <cr> <lf>
omitted:
EM <extend-0> <length> <STATUS> <AT Command response without trailing LF>
Example: Send +VRID=2 command to the modem and respond with terse caller ID:
EM <60h> <27h> <42h> +VRID=2
Note: <length> is 27h corresponding to 27h-1Fh=8. This is the length of the sequence following the <length> octet.
The modem responds to this command by transmitting the caller ID information to the DTE via the in-band sequence:
EM <60h> <length> <62h> <raw caller ID information>
EM<60h><22h><62h>OK
In this case, the <length> octet is the actual length of the raw caller ID + 1 + 1Fh.
In Band Signaling of CTS and Ring Indicate (Circuit 106 and Circuit 125)
Whenever the V.24 circuit selected via the +IBC command changes, the modem will send an unsolicited EM shielded
frame to the DTE to inform the DTE of the new state. This is used for CTS and RI. For MOH applications, the DTE is
specifically interested in circuit 125 (Ring Indicate).
When RI is asserted, the sequence EM <125on> or 19h 6Bh is sent to the DTE.
When RI is de-asserted, the sequence EM <125off> or 19h 6Ah is sent to the DTE.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
20
Chapter 4 - V.22bis Commands
V.22bis Call Control Commands
D
Dial
This command directs the modem to go on-line, dial according to the string entered and attempt to establish a
connection. If no dial string is supplied, the modem will go on-line and attempt the handshake in originate mode.
Note: If the ATD command is issued before the S1 register has cleared, the modem will respond with the NO
CARRIER result code.
The modem will behave as a data modem and will attempt to connect to another data modem. The modem will have
up to the period of time specified by register S6 or S7 to wait for carrier and complete the handshake. If this time
expires before the modem can complete the handshake, the modem will go on-hook with the NO CARRIER
response.
This command will be aborted while in progress (but before the completion of the handshake) upon receipt of any
DTE character.
Dial Modifiers
The valid dial string parameters are described below. Punctuation characters may be used for clarity, with
parentheses, hyphen, and spaces being ignored.
Syntax D<string>
Defined Values
<string> Character string corresponding to the selected option(s).
0-9 DTMF digits 0 to 9.
*
#
The 'star' digit (tone dialing only).
The 'gate' digit (tone dialing only).
A-D DTMF digits A, B, C, and D. Some countries may prohibit sending of these digits during dialing.
L
P
T
The modem will re-dial the last valid telephone number. The L must be immediately after the D with all the
following characters ignored.
Pulse dial the numbers that follow until a "T" is encountered. Affects current and subsequent dialing. Some
countries prevent changing dialing modes after the first digit is dialed.
Tone dial the numbers that follow until a "P" is encountered. Affects current and subsequent dialing. Some
countries prevent changing dialing modes after the first digit is dialed.
R
!
This command will be accepted, but not acted on.
Flash. the modem will go on-hook for a time defined by the value of S29. Country requirements may limit the
time imposed.
W
@
The modem will wait for dial tone before dialing the digits following "W". If dial tone is not detected within the time
specified by S7 (U.S.) or S6 (other countries), the modem will abort the rest of the sequence, return on-hook, and
generate an error message.
The modem will wait for at least 5 seconds of silence in the call progress frequency band before continuing with
the next dial string parameter. If the modem does not detect these 5 seconds of silence before the expiration of
the call abort timer (S7), the modem will terminate the call attempt with a NO ANSWER message. If busy
detection is enabled, the modem may terminate the call with the BUSY result code. If answer tone arrives during
execution of this parameter, the modem handshakes.
&
Wait for credit card dialing tone before continuing with the dial string. If the tone is not detected within the time
specified by S7 (U.S. models) or S6 (other countries), the modem will abort the rest of the sequence, return on-
hook, and generate an error message.
,
;
The modem will pause for a time specified by S8 before dialing the digits following ",".
Return to command state. Added to the end of a dial string, this causes the modem to return to the command
state after it processes the portion of the dial string preceding the ";". This allows the user to issue additional AT
commands while remaining off-hook. The additional AT commands may be placed in the original command line
following the ";" and/or may be entered on subsequent command lines. The modem will enter call progress only
after an additional dial command is issued without the ";" terminator. Use "H" to abort the dial in progress, and go
back on-hook.
^
Toggles calling tone enable/disable; applicable to current dial attempt only.
( ) Ignored; may be used to format the dial string.
Ignored; may be used to format the dial string.
-
<space> Ignored; may be used to format the dial string.
<i> Invalid character; will be ignored.
>
If enabled by country specific parameter, the modem will generate a grounding pulse on the EARTH relay output.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
21
Chapter 4 - V.22bis Commands
T
Set Tone Dial Default
This command forces DTMF dialing until the next P dial modifier or P command is received. The modem will set an
S-Parameter bit to indicate that all subsequent dialing should be conducted in tone mode. The DP command will
override this command. Clears S14 bit 5. This command may not be permitted in some countries. (See P.)
Result Code
OK
P
Set Pulse Dial Default
This command forces pulse dialing until the next T dial modifier or T command is received. Sets S14 bit 5.
As soon as a dial command is executed which explicitly specifies the dialing mod e for that particular call (e.g.;
ATDT), this command is overridden so that all future dialing will be tone dialed. (See T command.)
This command may not be permitted in some countries.
Result Code
OK
A
Answer
The modem will go off-hook and attempt to answer an incoming call if correct conditions are met. Upon successful
completion of answer handshake, the modem will go on-line in answer mode. This command may be affected by the
state of Line Current Sense, if enabled. (Most countries do not require Line Current Sense.) Operation is also
dependent upon country-specific requirements.
The modem will enter the connect state after exchanging carrier with the remote modem.
If no carrier is detected within a period specified in register S7, the modem hangs up.
Any character entered during the connect sequence will abort the connection attempt.
H
Disconnect (Hang-Up)
This command initiates a hang up sequence. It may not be available for some countries due to PTT restrictions.
Syntax H<value>
Defined Values
<value> Decimal number corresponding to the selected option.
0
The modem will release the line if the modem is currently on-line, and will terminate any test (AT&T) that is in
progress. Country specific, modulation specific, and error correction protocol specific (S38) processing is
handled outside of the H0 command.
1
If on-hook, the modem will go off-hook and enter command mode. For U.S., the modem will remain off-hook. For
other countries, the modem will return on-hook after a period of time determined by S7.
Result Codes
OK <value> = 0 or 1.
ERROR Otherwise.
O
Return to On-Line Data Mode
This command determines how the modem will enter the on-line data mode. If in the online command mode, the
modem enters the on-line data mode with or without a retrain. If in the off-line command mode (no connection), the
modem reports ERROR.
Syntax O<value>
Defined Values
<value> Decimal number corresponding to the selected option.
0
Enters on-line data mode without a retrain. Handling is determined by the Call Establishment task. Generally, if a
connection exists, this command connects the DTE back to the remote modem after an escape (+++).
Enters on-line data mode with a retrain before returning to on-line data mode.
1
Result Codes
OK <value> = 0 to 1 and a connection exists
ERROR Otherwise, or if not connected
L
Speaker Volume
This command sets the speaker volume control. The parameter value, if valid, is written to S22 bits 0 and 1.
Syntax L<value>
Defined Values
<value> Decimal number corresponding to the selected option.
0
1
2
3
Low volume.
Low volume. (Default)
Medium volume.
High volume.
Result Codes
OK <value> = 0 to 3
ERROR Otherwise
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
22
Chapter 4 - V.22bis Commands
M
Speaker Control
This command selects when the speaker will be on or off. The parameter value, if valid, is written to S22 bits 2 and 3.
Syntax M<value>
Defined Values
<value> Decimal number corresponding to the selected option.
0
1
2
3
Speaker is always off.
Speaker is on during call establishment, but off when receiving carrier. (Default)
Speaker is always on.
Speaker is off when receiving carrier and during dialing, but on during answering.
Result Codes
OK <value> = 0 to 3
ERROR Otherwise
&G
Select Guard Tone
This command causes the modem to generate the guard tone selected by this command (DPSK modulation modes
only). The parameter value, if valid, is written to S23 bits 6 and 7.
Syntax &G<value>
Defined Values
<value> Decimal number corresponding to the selected option.
0
1
2
Disables guard tone. (Default)
Disables guard tone.
Selects 1800 Hz guard tone.
This command may not be permitted in some countries.
Result Codes
OK <value> = 0 to 2
ERROR Otherwise
&P
Select Pulse Dial Make/Break Ratio
This command determines the make/break ratio used during pulse dialing. It is only effective if the appropriate bit to
enable this command is set through the country profile.
The default is country-dependent. The parameter value, if valid, is written to S28 bits 3 and 4.
Syntax &P<value>
Defined Values
<value> Decimal number corresponding to the selected option.
0
1
2
3
Selects 39%-61% make/break ratio at 10 pulses per second. (Default)
Selects 33%-67% make/break ratio at 10 pulses per second.
Selects 39%-61% make/break ratio at 20 pulses per second.
Selects 33%-67% make/break ratio at 20 pulses per second.
Result Codes
OK <value> = 0 to 3
ERROR Otherwise
&V
Display Current Configuration and Stored Profiles
This command reports the current (active) configuration.
Result Code
Example:
AT&V
OK
ACTIVE PROFILE:
B1 E1 L1 M1 N0 QO T V1 W0 X4 Y0 &C1 &D2 &G0 &J0 &K3 &Q5
&R1 &S0 &T5 &X0
S00:000 S01:000 S02:043 S03:013 S04:010 S05:008 S06:002
S07:050 S08:002 S09:006
S10:014 S11:085 S12:050 S18:000 S25:005 S26:001 S36:007
S38:020 S46:138
S48:007 S95:000
OK
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
23
Chapter 4 - V.22bis Commands
\V
Single Line Connect Message Enable
This command enables or disables the single line connect message format as follows:
Syntax \V<value>
Defined Values
<value> Decimal number corresponding to the selected option.
0
1
Connect messages are controlled by the command settings X, W, and S95.
Connect messages are displayed in the single line format described below subject to the command settings V
(Verbose) and Q (Quiet). In Non-Verbose mode (V0), single line connect messages are disabled and a single
numeric result code is generated for CONNECT DTE.
When single line connect messages are enabled, there are no CARRIER or PROTOCOL (+ER:) messages apart
from the fields described below.
The single line connect message format is:
CONNECT <DTE Speed>/<Modulation>/<Protocol>/<Compression>/<Line Speed>
Where:
DTE Speed =
Modulation =
DTE speed, e.g., 2400.
“V21” for V.21 modulation.
“B103” for Bell 103 modulation.
“B212” for Bell 212A modulation.
“V22” for V.22 modulation.
“V22B” for V.22bis modulation.
“V23C” for V.23 modulation.
Note: Modulation is omitted for all other modulations.
“NONE” for no protocol.
Protocol =
“ALT” for Microcom Network Protocol.
“LAPM” for LAP-M protocol.
Line Speed =
Asymmetric rates are displayed as “/rate:TX/rate:RX”, e.g., /1200 TX/75 RX.
Symmetric rates are displayed as a single DCE rate, e.g., 2400.
%L
Report Line Signal Level
Returns a value which indicates the received signal level. The value returned is a direct indication (DAA dependent)
of the receive level at the MDP, not at the telephone line connector. For example, 009 = -9 dBm, 043 = -43 dBm, and
so on.
Result Code
OK
%Q
Report Line Signal Quality
Reports the line signal quality (DAA dependent). Returns the higher order byte of the EQM value. Based on the EQM
value, retrain may be initiated if enabled by %E1.
Example:
AT%Q
015
Result Codes
OK if connected
ERROR if not connected, or connected in 300 bps or V.23 modes
*B
Display Blacklisted Numbers
This command requests the modem to return a list of blacklisted numbers to the DTE. The format of the response is
shown by the example below. Permanently forbidden numbers as defined by country requirements will not appear on
this list. If no numbers are blacklisted, only the OK result code is issued.
Syntax *B
Example
NO. - PHONE NUMBER -
------ ------------------------------
1; 4175537660
2; 8288924961
3; 3887278862
4; 3124839442
5; 6284664
OK
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
24
Chapter 4 - V.22bis Commands
*D
Display Delayed Numbers
This command causes the modem to send a list of the delayed numbers together with the delay associated with
each. The modem will return a list of delayed telephone numbers as defined in the *B command. The format of the
response is shown by the example below (delay times are shown as hours:minutes:seconds). If no numbers are
delayed, only the OK result code is issued.
Syntax *D
Example
NO. - PHONE NUMBER -DELAY
------ -------------------------------------------
1; 8264734660 2:00:00
2; 7532634661 2:00:00
3; 2587334662 0:02:00
4; 7532651663 0:03:25
5; 7459931664 0:01:45
OK
–STE= Set Telephony Extension
The –STE command enables/disables Line-in-Use, Extension Pickup, and Remote Hangup detection features.
Note: Additional hardware may be required to support these features.
Syntax -STE=<value>
Defined Values
<value> Decimal number corresponding to the selected bit-mapped options. The bit fields are defined as follows:
Bit 0 Line-in-Use detection enable/disable.
Bit 1 Extension Pickup detection enable/disable.
Bit 2 Remote Hangup detection enable/disable.
<value> (Dec.)
0 (default)
Remote Hangup
Disabled
Disabled
Disabled
Disabled
Enabled
Enabled
Enabled
Enabled
Extension Pickup
Disabled
Disabled
Enabled
Enabled
Disabled
Disabled
Enabled
Enabled
Line-in-Use
Disabled
Enabled
Disabled
Enabled
Disabled
Enabled
Disabled
Enabled
1
2
3
4
5
6
7
Reporting Current or Selected Values
Command: -STE?
Response: -STE: <value>
Example: -STE: 4 Remote Hangup enabled, Extension Pickup disabled, and Line-in-Use disabled.
Reporting Supported Range of Parameter Values
Command: -STE=? Show available options.
Response: -STE: 0-7
Result Codes
OK <value> = 0-7
ERROR Otherwise
Behavior in Data Mode
When on-hook, if the line is in use and an ATDT is issued, the modem will not go off hook and will return with the
message “LINE IN USE”.
When off-hook and either an extension is picked up or a line reversal is detected, the modem will drop the
connection. The disconnect reason in register S86=25. The user must flash the hook in order to get a dial tone due
because the remote server will be retraining.
If the local handset is picked up while the modem is off-hook, the modem will do a link disconnect, flash the hook for
1.5 seconds, and then connect the local handset to the line. At this point, the user dial tone should be on the local
handset. The disconnect reason in S86=25.
Operation in Data Mode
Line-in-Use (Enabled by AT-STE=1, AT-STE=3, AT-STE=5, or AT-STE=7)
Case 1: Telephone Line is in Use
If an ATDT, ATDP or ATDL is issued while Line-in-Use detection is enabled and the telephone line is in use, the
modem will immediately return the message “LINE IN USE” to the DTE without going off-hook, and then return to
command mode.
Case 2: Telephone Line is in Use, But Disconnected
If an ATDT, ATDP or ATDL is issued while Line-in-Use detection is enabled and the telephone line is NOT in
use, the modem will go off-hook after a short pause, then respond with CONNECT or NO CARRIER message.
Case 3: Telephone Line is Not Connected to Modem
If an ATDT, ATDP or ATDL is issued while Line-in-Use detection is enabled and the telephone line is not
connected, the modem will go off-hook momentarily, go back onhook, then respond with NO DIAL TONE
message.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
25
Chapter 4 - V.22bis Commands
Extension Pick-up (Enabled by AT-STE=2, AT-STE=3, AT-STE=6, or AT-STE=7):
Case 1: Modem off-hook, Local Handset Goes Off-Hook
If the local handset goes off-hook while the modem is in a data connection, the local handset will be muted. The
modem will then send a GSTN Cleardown to the remote modem and then go on-hook. The modem will then
send a NO CARRIER message to the DTE. A result code of 25 will be left in S86 register. After 2 seconds, the
local handset will be connected to the telephone line so the user hears the dial tone.
Case 2: Modem off-hook, Extension Pick-up
If the modem is connected and another extension goes off-hook, the modem will send a GSTN Cleardown to the
remote modem and then immediately hang-up. Due to the noise possibly being added to the line when a
telephone extension is picked-up, a GSTN Cleardown may or may not successfully be received by the remote
mode. If the GSTN Cleardown is not received successfully by the remote modem, the remote modem may
attempt a retrain until the retrain fails and the remote modem drops the line. In any case, the modem will send a
NO CARRIER message to the DTE immediately after sending the GSTN Cleardown. A result code of 25 will be
left in the S86 register. Because the extension is off-hook, the modem cannot flash the hook for the central office
to generate a dial tone. In this case, the user must flash the extension handset to obtain a dial tone.
Remote Hang-up (enabled by AT-STE=4, AT-STE=5, AT-STE=6, or AT-STE=7):
Case 1: Modem off-hook, Remote Hang-up
If the modem is connected (off-hook) and the remote modem/server goes hangs up, the central office may issue
a line polarity reversal. If a line polarity reversal is detected, the modem will drop the call and respond with NO
CARRIER. The reason for hang-up can be determined by S86=25. A line reversal can also be simulated by
simply pulling out the telephone line during a connection.
+PCW Call Waiting Enable
This command controls the operation of the modem in the presence of call waiting.
Syntax +PCW=<value>
Defined Values
<value> Decimal number corresponding to the selected operation.
0
1
2
Collect caller ID information if enabled by +VRID. Toggle V.24 circuit 125. (Default)
Hang-up.
Ignore call waiting.
Result Codes
OK <value> = 0, 1, or 2
ERROR Otherwise
Reporting Selected Value(s)
Command: +PCW?
Response: +PCW: <value>
Example: +PCW: 0 For the default setting.
Reporting Supported Range of Parameter Values
Command: +PCW=?
Response: +PCW: (<value> range)
Example: +PCW: (0,1,2)
+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
1
The modem will not report ring cadence information.
The modem will report ring cadence information as specified for the <report> subparameter.
<report>
Decimal number specifying ring cadence information report when enabled by <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. Modem will produce a RING event
code after <report>/10 seconds after the falling edge of the ring pulse (i.e., after DRON report).
Reporting Current or Selected Values
Command: +VDR?
Response: <enable>,<report>
Example: 0,0 For the default setting.
Reporting Supported Range of Parameter Values
Command: +VDR=?
Response: (<enable> range),(<report>range)
Example: (0,1),(0-6)
Result Codes
OK <enable>,<report> = (0,1),(0-6)
ERROR Otherwise, or if not in Voice Mode
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
26
Chapter 4 - V.22bis Commands
V.22bis Modulation Control Commands
+MS
Modulation Selection
This extended-format compound parameter controls the manner of operation of the modulation capabilities in the
modem. It accepts six subparameters.
Syntax
+MS=[<carrier>[,<automode>[,<min_tx_rate>[,<max_tx_rate>[,<min_rx_rate>[,<max_rx_rate>]]]]]]
Table of +MS Command Supported Rates
Modulation
<carrier>
Possible (<min_rx_rate>, <min_rx_rate>, (<min_tx_rate>),
and <max_tx_rate>) Rates (bps)
Bell 103
Bell 212
V.21
B103
B212
V21
300
1200 Rx/75 Tx or 75 Rx/1200 Tx
300
V.22
V22
1200
V.22bis
V.23
V22B
V23C
2400 or 1200
1200
Defined Values
<carrier>
A string which specifies the preferred modem carrier to use in originating or answering a connection.
<carrier> values are strings of up to eight characters, consisting only of numeric digits and upper case
letters. <carrier> values for ITU standard modulations take the form: <letter><1-4 digits><other letters
as needed>.
<automode> A numeric value which enables or disables automatic modulation negotiation (e.g., V.22bis).
0 = Automode disabled.
1 = Automode enabled. (Default)
<min_rx_rate> and <max_rx_rate>
Numeric values which specify the lowest (<min_rx_rate>) and highest (<max_rx_rate>) rate at which
the modem may establish a receive connection. May be used to condition distinct limits for the receive
direction as distinct from the transmit direction. Values for this subparameter are decimal encoded, in
units of bit/s. Actual values will be limited to possible values corresponding to the entered <carrier> and
fall-back <carrier> as determined during operation. (Default = lowest (<min_rx_rate>) and highest
(<max_rx_rate>) rate supported by the selected carrier.)
<min_tx_rate> and <max_tx_rate>
Numeric values which specify the lowest (<min_tx_rate>) and highest (<max_tx_rate>) rate at which the
modem may establish a transmit connection. Non-zero values for this subparameter are decimal
encoded, in units of bit/s. Actual values will be limited to possible values corresponding to the entered
<carrier> and fall-back <carrier> as determined during operation. (Default = lowest (<min_tx_rate>) and
highest (<max_tx_rate>) rate supported by the selected carrier.)
Reporting Current or Selected Values
Command: +MS?
Response: +MS:<carrier>,<automode>,<min_tx_rate>, <max_tx_rate>,<min_rx_rate>,<max_rx_rate>
Example: +MS: V22B, 1,300,2400,300,2400
For default values. This example allows maximum system flexibility to determine optimal receive and transmit rates
during operation.
Reporting Supported Range of Parameter Values
Command: +MS=?
Response: +MS: (< carrier> range),(<automode> range),(<min_tx_rate> range),(<max_tx_rate> range),
(<min_rx_rate> range), (<max_rx_rate> range)
Example 1: +MS:(B103,B212,V21,V22,V22B,V23C),(0,1),(300-2400),(300-2400),(300-2400),(300-2400)
Result Code
OK Valid subparameter string
ERROR Otherwise
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
27
Chapter 4 - V.22bis Commands
%E
Enable/Disable Line Quality Monitor and Auto-Retrain
Controls whether or not the modem will automatically monitor the line quality and request a retrain (%E1). The
parameter value, if valid, is written to S41 bits 2 and 6. If enabled, the modem attempts to retrain for a maximum of 30
seconds.
Syntax %E<value>
Defined Values
<value> Decimal number corresponding to the selected option.
0
Disable line quality monitor and auto-retrain.
1
Enable line quality monitor and auto-retrain. (Default)
Result Codes
OK <value> = 0 or 2.
ERROR Otherwise.
B
ITU-T or Bell
When the modem is configured to allow either option, the modem will select Bell or ITUT modulation for a line speed
connection of 300 or 1200 bps. Any other line speed will use an ITU-T modulation standard. The parameter value, if
valid, is written to S27 bit 6..
Syntax
B<value>
Defined Values
<value> Decimal number corresponding to the selected option.
0
1
2
3
Selects ITU-T operation at 300 or 1200 bps during Call Establishment and a subsequent connection. (Default)
Selects Bell operation at 300 or 1200 bps during Call Establishment and a subsequent connection.
Selects V.23 half-duplex operation at 1200 bps during Call Establishment and a subsequent connection.
Disables V.23 half-duplex operation.
Result Codes
OK <value> = 0 or 3
ERROR Otherwise
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
28
Chapter 4 - V.22bis Commands
V.22bis Error Control and Data
Compression Commands
+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.
Reporting Current or Selected Values:
Command: +ESR?
Response: +ESR: <value>
Example: +ESR: 0 For default setting
+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)
\B
Transmit Break to Remote
In non-error correction mode, the modem will transmit a break signal to the remote modem with a length in multiples
of 100 ms according to parameter specified. If a number in excess of 9 is entered, 9 is used. The command works in
conjunction with the \K command.
In error correction mode, the modem will signal a break through the active error correction protocol, giving no
indication of the length.
Syntax \B<value>
Defined Values
<value> Decimal number corresponding to the selected option.
1-9
Break length in 100 ms units. (Default = 3.)
(Non-error corrected mode only.)
Result Codes
OK
If connected in data modem mode
NO CARRIER If not connected.
Note: When the modem receives a break from the remote modem, break is passed to the DTE as follows: In non-
error correction mode direct, the break length is passed; in non-error correction mode normal and in error correction
mode, a 300 ms break is passed.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
29
Chapter 4 - V.22bis Commands
\K
Break Control
Controls the response of the modem to a break received from the DTE or the remote modem or the \B command.
The parameter value, if valid, is written to S40 bits 3, 4, and 5.
Syntax \K<value>
Defined Values
<value> Decimal number corresponding to the selected option.
The response is different in three separate states.
The first state is where the modem receives a break from the DTE when the modem is operating in data transfer
mode:
0
1
2
3
4
5
Enter on-line command mode, no break sent to the remote modem.
Clear data buffers and send break to remote modem.
Same as 0.
Send break to remote modem immediately.
Same as 0.
Send break to remote modem in sequence with transmitted data. (Default)
The second case is where the modem is in the on-line command state (waiting for AT commands) during a data
connection, and the \B is received in order to send a break to the remote modem:
0
1
2
3
4
5
Clear data buffers and send break to remote modem.
Clear data buffers and send break to remote modem. (Same as 0.)
Send break to remote modem immediately.
Send break to remote modem immediately. (Same as 2.)
Send break to remote modem in sequence with data.
Send break to remote modem in sequence with data. (Same as 4.) (Default)
The third case is where a break is received from a remote modem during a non-error corrected connection:
0
1
2
3
4
5
Clears data buffers and sends break to the DTE.
Clears data buffers and sends break to the DTE. (Same as 0.)
Send a break immediately to DTE.
Send a break immediately to DTE. (Same as 2.)
Send a break in sequence with received data to DTE.
Send a break in sequence with received data to DTE. (Same as 4.) (Default)
Result Codes
OK 0 to 5
ERROR Otherwise
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
30
Chapter 4 - V.22bis Commands
V.22bis Synchronous Access Mode
Commands
Three commands support Synchronous Access Mode:
+ES enables and disables Synchronous Access Mode in the client or central site modem. Enabling Synchronous
Access Mode enables the use of the 8-bit command characters of the Draft ITU-T Recommendation V.80 (See
the table under the +IBC command - Data Communication over the Telephone Network. In-Band DCE Control
Command).
+ESA configures the operation of the Synchronous Access Submode
+ITF selects Transmit Flow Control Thresholds
+ESA Configure Synchronous Access Submode
The operation of the Synchronous Access sub-Mode is configured by the +ESA parameter..
This extended-format compound parameter is used to control the manner of operation of the Synchronous Access
Mode in the modem. It accepts six numeric subparameters:
Syntax
+ESA=[<trans_idle>[,<framed_idle>[,<framed_un_ov>[,<hd_auto>[,<crc_type>[,<nrzi_en>[,<syn1>[,<syn2>]]]]]]]]
Defined Values
<trans_idle>
Specifies the bit sequence transmitted by the modem when a transmit data buffer under run
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>
Specifies the bit sequence transmitted by the modem when a transmit data buffer under run
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> Specifies the actions undertaken by the modem when a transmit data buffer under run or overrun
condition occurs immediately after a non-flag octet, while operating in Framed sub-Mode.
0
1
In Framed sub-Mode, modem transmits abort on under run in middle of frame (default).
In Framed sub-Mode, DCE transmits a flag on under run in middle of frame, and notifies
DTE of under run or over run.
<hd_auto>
<crc_type>
This subparameter should not be commanded.
Specifies the CRC polynomial used while operating in Framed sub-Mode. The options are:
0
1
CRC generation and checking disabled (default).
In Framed sub-Mode, the 16-bit CRC is generated by the modem in the transmit direction,
and checked by the modem in the receive direction.
<nrzi_en>
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> 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 Selected Options
The modem reports the selected options in response to the following command:
+ESA?
The response is:
+ESA:
<trans_idle>,<framed_idle>,<framed_un_ov>,<hd_auto>,<crc_type>,<nrzi_en>,<syn1>,<syn2>
Example:
+ESA?
+ESA: 0,0,0, ,0,0,255, For the defaults.
Reporting Supported Options
The modem reports the supported options in response to the following command:
+ESA=?
The response is:
+ESA: (list of supported <trans_idle> values), (list of supported <framed_idle>values),(list of supported
<framed_un_ov> values), (list of supported <hd_auto>values),(list of supported <crc_type> values), (list of supported
<nrzi_en> values),(list of supported <syn1> values), (list of supported <syn2> values)
Example:
+ESA=?
+ESA: (0),(0),(0-1), ,(0-1),(0),(255),
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
31
Chapter 4 - V.22bis Commands
+ITF
Transmit Flow Control Thresholds
The +ITF command determines the flow control thresholds used by the modem for transmit data from the DTE. This
optional compound parameter allows the DTE to determine the input buffer size in the modem for data on circuit 103
(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. The DTE can adjust its own thresholds for flow control
of data on circuit 104 (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 and Frame Tunneling modes. Default <off> value is 255.
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 DC1 and DC3 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 not
modified.
<on> Determines the threshold, in octets, below which the modem will generate a flow on signal. Applicable in
Synchronous Access and Frame-Tunneling modes. Default <on> value is 64.
<report_period> Not supported. A fixed value of zero is used and reported.
Reporting Selected Options
The modem sends a string of information text to the DTE consisting of selected options in response to the following
command:
+ITF?
The response is:
+ITF: <off>,<on>,<report_period>
Example:
+ITF?
+ITF: 255,64,0 Default values
Reporting Supported Options
The modem sends a string of information text to the DTE consisting of supported options in response to the following
command:
+ITF=?
The response is:
+ITF: (list of supported <off> values),(list of supported <on> values),(list of supported <report_period> values)
Example:
+ITF=?
+ITF: (0-255),( 0-255),(0)
The maximum reported <off> value is the input transmit data buffer level at which the modem signals a transmit data
overrun indication to the DTE.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
32
Chapter 4 - V.22bis Commands
V.22bis FastConnect Command
$F
Fast Connect Control
This command allows configuring of the client modem to connect to a central site modem that supports non-standard
V.22 and V.22bis Fast Connect protocols.
Syntax
$F<n>
Defined Values
<n> Decimal number which specifies the initial requested mode of operation when the modem is operating as the
originator. The options are:
0
1
2
3
Normal connection (Default)
Fast Connect without answer tone
Reserved
Fast Connect with answer tone
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
33
Chapter 4 - V.22bis Commands
V.22bis Line Side Device Commands
-TTE
Threshold Adjustments for Telephony Extension
This command allows the host to set/tune the telephone line voltage level drop threshold necessary for the modem to
determine Line-in-Use, Extension Pickup, and Remote Hangup conditions. An ATZ or AT&F will load default values.
Syntax
-TTE=<Line-in-Use voltage drop threshold>,<Extension Pickup voltage drop threshold>, <Remote Hangup voltage
drop threshold>
Defined Values
Range =(0-9999), (0-9999), (0-9999)
Units: 1/10 volt
<Line-in-Use voltage drop threshold>
default: 1000 (10.00 V drop while modem onhook)
<Extension Pickup voltage drop threshold>
default: 200 (2.00 V drop while modem offhook) this value must be less than the Remote Hangup voltage
drop threshold
<Remote Hangup voltage drop threshold>
default: 500 (5.00 V drop while modem offhook) this value must be greater than the Extension Pickup
voltage drop threshold
AT-TTE? Queries current setting
Notes:
1. All thresholds are difference thresholds. Example: The line would be considered “in use” if the Tip & Ring Voltage
dropped by 10.00 volts. Another Example: If the modem is off hook and the voltage drops by more than 2.50
volts, then the modem would consider the condition as an extension pick up.
2. The <Remote Hangup voltage drop threshold> must always be less than the <Extension Pickup voltage drop
threshold). Otherwise, the extension pickup will not function.
-TRV
Tip and Ring Voltage Measurement
This command measures and reports the telephone line voltage level at Tip and Ring while on-hook or in off-hook
command mode. If an application does not want to enable the telephony extension features through the –STE
command, the voltage value may be obtained using the -TRV command instead. This is also a very useful debug
command.
Syntax
-TRV
Defined Values
Units: Volts
Response
xx.yy Example: A value of 30.50 indicates 30.50 V.
OK The lowest value reported by the modem is 1.40 V based on conversion formula.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
34
Chapter 4 - V.22bis Commands
V.22bis S-Parameters
The S-Parameters are summarized in the S-Parameter Table along with their default values which may be loaded at
any time by using the Z command. Registers or register fields quoted as “reserved” are reserved for current or future
use by the firmware or are permanently overridden by PTT limitations. For the latter, control of the equivalent
functionality is available with Blacklisting options.
All bit-mapped registers are read-only. The appropriate AT command, which controls the relevant bits in the S-
Parameter should be used to change the value.
S - Read/Write S-Parameter
The modem selects an S-Parameter, performs an S-Parameter read or write function, or reports the value of an S-
Parameter.
n
Establishes S-Parameter n as the last register accessed.
n=v Sets S-Parameter n to the value v.
n? Reports the value of S-Parameter n.
The parameter n can be omitted, in which case the last S-Parameter accessed will be assumed. The S can be
omitted for AT= and AT?, in which case the last S-Parameter accessed will be assumed. For example:
ATS7 establishes S7 as the last accessed register.
AT=40 sets the contents of the last register accessed to 40.
ATS=20 sets the contents of the last register accessed to 20.
If the number "n" is outside the range of the S-Parameters available, the modem will return the ERROR message. If
the value “v” is outside the range permitted for a given SParameter, the modem will return the ERROR message.
Input and output are always in decimal format. Note that some S-Parameters are read-only.
In some cases, writing to the S-Parameter will appear to be accepted but the value will not actually be written.
Due to country restrictions, some commands will be accepted, but the value may be limited and replaced by a
maximum or minimum value.
Minimum, maximum, and default values for S-Parameters may be altered by inserting a country profile using patch
code.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
35
Chapter 4 - V.22bis Commands
Summary of S-Parameter Defaults
Register
S0
Function
Range/Units
0-255 rings
0-255 rings
0-255 ASCII
0-127 ASCII
0-127 ASCII
0-255 ASCII
Default*
0
0
43
13
10
8
Rings to Auto-Answer
Ring Counter
Escape Character
Carriage Return Character
Line Feed Character
S1
S2
S3
S4
S5
Backspace Character
S6
S7
S8
S9
Wait Time before Blind Dialing or for Dial Tone
Wait Time for Carrier, Silence, or Dial Tone
Pause Time for Dial Delay Modifier
Carrier Detect Response Time
Lost Carrier To Hang Up Delay
DTMF Tone Duration
Escape Prompt Delay (EPD)
General Bit Mapped Options Status
Test Mode Bit Mapped Options Status
Reserved
2-255
1-255
2-255
1-255 0.1 s
1-255 0.1 s
50-255 0.001 s
0-255 0.02 s
s
s
s
2
50
2
6
14
85
50
138 (8Ah)
S10
S11
S12
S14
S16
S19
S20
S21
S22
S23
S24
S25
S26
S27
S28
S29
S30
S31
S36
S38
S39
S40
S41
S86
S91
0
0
0
Reserved
V.24/General Bit Mapped Options Status
Speaker/Results Bit Mapped Options Status
General Bit Mapped Options Status
Sleep Inactivity Timer
Delay to DTR Off
RTS-to-CTS Delay
General Bit Mapped Options Status
General Bit-Mapped Options Status
Flash Dial Modifier Time
Disconnect Inactivity Timer
General Bit-Mapped Options Status
LAPM Failure Control
Delay Before Forced Hangup
Flow Control Bit Mapped Options Status
General Bit-Mapped Options Status
General Bit-Mapped Options Status
Call Failure Indication
52 (34h)
117 (75h)
0
0
5
0-255
0-255 s or 0.01 s
0-255 0.01 s
s
1
73 (49h)
0
70
0
192 (C0h)
7
20
3
104 (68h)
195 (C3h)
21
10 (Country
dependent)
0
0-255 10 ms
0-255 10 s
0-255
s
0-26
0-15
PSTN Transmit Attenuation Level
dBm
S95
Extended Result Codes Control
* Default values may be modified using patch code.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
36
Chapter 4 - V.22bis Commands
S-PARAMETER DEFINITIONS
S0 - Number of Rings to Auto-Answer
S0 sets the number of the rings required before the modem automatically answers a call.
Setting this parameter to zero disables auto-answer mode.
Range: 0-255 rings
Default: 0
S1 - Ring Counter
S1 is incremented each time the modem detects a ring signal on the telephone line. S1 is cleared if no rings occur
over an eight second interval.
Range: 0-255 rings
Default: 0
S2 - Escape Character
S2 holds the decimal value of the ASCII character used as the escape character. The default value corresponds to an
ASCII '+'. A value over 127 disables the escape process, i.e., no escape character will be recognized.
Range: 0-255, ASCII decimal
Default: 43 (+)
S3 - Carriage Return Character
S3 sets the command line and result code terminator character. Pertains to asynchronous operation only.
Range: 0-127, ASCII decimal
Default: 13 (Carriage Return)
S4 - Line Feed Character
S4 sets the character recognized as a line feed. Pertains to asynchronous operation only. The Line Feed control
character is output after the Carriage Return control character if verbose result codes are used.
Range: 0-127, ASCII decimal
Default: 10 (Line Feed)
S5 - Backspace Character
S5 sets the character recognized as a backspace. Pertains to asynchronous operation only. The modem will not
recognize the Backspace character if it is set to a value that is greater than 32 ASCII. This character can be used to
edit a command line. When the echo command is enabled, the modem echoes back to the local DTE the Backspace
character, an ASCII space character and a second Backspace character; this means a total of three characters are
transmitted each time the modem processes the Backspace character.
Range: 0-32, ASCII decimal
Default: 8 (Backspace)
S6 - Wait Time before Blind Dialing or for Dial Tone
S6 operation is country dependent.
1. Sets the length of time, in seconds, that the modem will wait before starting to dial after going off-hook when
blind dialing. This operation, however, may be affected by some ATX options according to country restrictions.
The “Wait for Dial Tone” call progress feature (W dial modifier in the dial string) will override the value in register
S6. (U.S.)
2. Sets the length of time, in seconds, that the modem will wait for dial tone when encountering a “W” dial modifier
before returning NO DIAL TONE result code. (Other countries.)
The modem always pauses for a minimum of 2 seconds, even if the value of S6 is less than 2 seconds.
Range: 2-255 seconds
Default: 2
S7 - Wait Time for Carrier, Silence, or Dial Tone
S7 operation is country dependent.
1. Sets the length of time, in seconds, that the modem will wait for carrier before hanging up. The timer is started
when the modem finishes dialing (originate), or 2 seconds after going off-hook (answer). In originate mode, the
timer is reset upon detection of answer tone if allowed by country restrictions.
2. Sets the length of time, in seconds, that modem will wait for silence when encountering the @ dial modifier
before continuing with the next dial string parameter.
3. Sets the length of time, in seconds, that the modem will wait for dial tone when encountering a “W” dial modifier
before continuing with the next dial string parameter. (U.S.)
Range: 1-255 seconds
Default: 50
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
37
Chapter 4 - V.22bis Commands
S8 - Pause Time For Dial Delay
S8 sets the time, in seconds, that the modem must pause when the “,” dial modifier is encountered in the dial string.
Range: 2-255 seconds
Default: 2
S9 - Carrier Detect Response Time
S9 is supported for backwards compatibility only. No value can be written. Responds with default value.
Range: 6 tenths of a second
Default: 6 (0.6 second)
S10 - Lost Carrier To 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)
S11 - DTMF Tone Duration
S11 operation is country dependent.
1. For U.S., S11 sets the duration of tones in DTMF dialing (has no effect on pulse dialing).
2. For other countries, S11 is a country parameter loaded via patch code.
Range: 50-255 milliseconds
Default: 95 (95 milliseconds)
S12 - Escape Prompt Delay (EPD)
S12 defines the maximum period, in fiftieths of a second, allowed between receipt of the last character of the three
escape character sequence from the DTE and sending of the OK result code to the DTE. If any characters are
detected during this time, the OK will not be sent. Sending of the OK result code does not affect entry into command
mode.
Range: 0-255 1/50 of a second
Default: 50 (1 second)
S14 - General Bit Mapped Options Status
S14 indicates the status of command options.
Default: 138 (8Ah) (10001010b)
Bit 0 This bit is ignored.
Bit 1 Command echo (En).
0 = Disabled (E0).
1 = Enabled (E1). (Default)
Bit 2 Quiet mode (Qn).
0 = Send result codes (Q0). (Default)
1 = Do not send result codes (Q1).
Bit 3 Result codes (Vn).
0 = Numeric (V0).
1 = Verbose (V1). (Default)
Bit 4 Reserved.
Bit 5 Tone (T)/Pulse (P).
0 = Tone (T). (Default)
1 = Pulse (P).
Bit 6 Reserved.
Bit 7 Originate/Answer.
0 = Answer.
1 = Originate. (Default)
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
38
Chapter 4 - V.22bis Commands
S16 - Test Mode Bit Mapped Options Status
S16 indicates the test in progress status.
Default: 0
Bit 0 Local analog loopback.
0 = Disabled. (Default)
1 = Enabled. (&T1)
Bit 1 Not used
Bit 2 Local digital loopback
0 = Disabled (default)
1 = Enabled (&T3)
Bit 3 Remote digital loopback (RDL) status
0 = Modem not in RDL
1 = RDL in progress
Bit 4 RDL requested (AT&T6)
0 = RDL not requested (default)
1 = RDL requested (&T6)
Bit 5 RDL with self test
0 = Disabled (default)
1 = Enabled (&T7)
Bit 6 Local analog loopback (LAL) with self test
0 = Disabled (default)
1 = Enable (&T8)
Bit 7 --- Not used
S19 - Reserved
S19 is supported for backwards compatibility only. No value can be written. Responds with default value.
Range: None
Default: 0
S20 - Reserved
S20 is supported for backwards compatibility only. No value can be written. Responds with default value.
Range: None
Default: 0
S21 - V.24/General Bit Mapped Options Status
S21 indicates the status of command options.
Default: 52 (34h) (00110100b)
Bits 0 - 1 Telephone Jack Control (&Jn).
0 = &J0 selected. (Default)
1 = &J1 selected.
2 = &J2 selected.
3 = &J3 selected.
Bit 2 CTS behavior (&Rn).
0 = CTS tracks RTS (&R0).
1 = CTS always on (&R1). (Default)
Bits 3-4 DTR behavior (&Dn).
0 = &D0 selected.
1 = &D1 selected
2 = &D2 selected. (Default)
3 = &D3 selected.
Bit 5 RLSD behavior (&Cn).
0 = &C0 selected.
1 = &C1 selected. (Default)
Bit 6 DSR behavior (&Sn).
0 = &S0 selected. (Default)
1 = &S1 selected.
Bit 7 Long space disconnect (Yn).
0 = Y0. (Default)
1 = Y1.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
39
Chapter 4 - V.22bis Commands
S22 - Speaker/Results Bit Mapped Options Status
S22 indicates the status of command options.
Default: 117 (75h) (01110101b)
Bits 0-1 Speaker volume (Ln).
0 = Off (L0).
1 = Low (L1). (Default)
2 = Medium (L2).
3 = High (L3).
Bits 2-3 Speaker control (Mn).
0 = Disabled (M0).
1 = Off on carrier (M1). (Default)
2 = Always on (M2).
3 = On during handshake (M3).
Bits 4-6 Limit result codes (Xn).
0 = X0.
4 = X1.
5 = X2.
6 = X3.
7 = X4. (Default)
Bit 7 Reserved.
S23 - General Bit Mapped Options Status
S23 indicates the status of command options.
Default: 0
Bits 0-6 Not used.
Bits 6-7 Guard tone (&Gn).
0 = None (&G0). (Default)
1 = None (&G1).
2 = 1800 Hz (&G2).
S24 - Sleep Inactivity Timer
S24 sets the length of time, in seconds, that the modem will operate in normal mode with no detected telephone line
or DTE line activity before entering low-power sleep mode. The timer is reset upon any DTE line or telephone line
activity. If S24 is zero, neither DTE line nor telephone inactivity will cause the modem to enter the sleep mode.
Range: 0-255 seconds
Default: 0
S25 - Delay To DTR Off
S25 sets the length of time that the modem will ignore DTR for taking the action specified by &Dn. Its units are
seconds for synchronous modes and one hundredths of a second for other modes.
Range: 0-255 (1 second for synchronous modes 1; 0.01 second otherwise)
Default: 5
S26 - RTS to CTS Delay
S26 sets the time delay, in hundredths of a second, before the modem turns CTS ON after detecting an OFF-to-ON
transition on RTS when &R0 is commanded. Pertains to synchronous operation only.
Range: 0-255 hundredths of a second
Default: 1
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
40
Chapter 4 - V.22bis Commands
S27 - Bit Mapped Options Status
S27 indicates the status of command options.
Default: 73 (49h) (01001001b)
Bits 0,1,3 Synchronous/asynchronous selection (&Mn/&Qn).
31
0
0 0
0 0
0 1
0 1
10
0 = &M0 or &Q0.
1 = &M1 or &Q1.
0 = &M2 or &Q2.
1 = &M3 or &Q3.
0 = Reserved.
1 = &Q5. (Default)
0 = &Q6.
1 0
11
Bit 2 Leased line control (&Ln).
0 = Dial up line (&L0). (Default)
Bits 4 - 5 Internal clock select (&Xn).
0 = Internal clock (&X0). (Default)
1 = External clock (&X1).
2 = Slave clock (&X2).
Bit 6 ITU-T/Bell mode select (Bn).
0 = ITU-T mode (B0).
1 = Bell mode (B1). (Default)
Bit 7 Reserved.
S28 - Bit Mapped Options Status
S28 indicates bit mapped options status.
Default: 0
Bits 0 - 1 Reserved.
Bit 2 Reserved (always 0).
Bits 3 - 4 Pulse dialing (&Pn)
0 = 39%-61% make/break ratio at 10 pulses per second (&P0). (Default)
1 = 33%-67% make/break ratio at 10 pulses per second (&P1).
2 = 39%-61% make/break ratio at 20 pulses per second (&P2).
3 = 33%-67% make/break ratio at 20 pulses per second (&P3).
Bit 5-7 Reserved
S29 - Flash Dial Modifier Time
S29 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. S29 is a country dependent parameter. The S29 value cannot be changed using S29=XX.
Range: 0-255 10 ms intervals
Default: 70 (700 ms) for U.S.
S30 - Disconnect Inactivity Timer
S30 sets the length of time, in tens of seconds, that the modem will stay online before disconnecting when no data is
sent or received. In error-correction mode, any data transmitted or received will reset the timer. In other modes, any
data transmitted will reset the timer. The timer is inoperative in synchronous mode.
Range: 0-255 tens of seconds (0-2550 seconds)
Default: 0 (disabled)
S31 - Bit Mapped Options Status
S31 indicates bit mapped options status.
Default: 192 (C0h) (11000000b)
Bit 0 Single line connect message enable/disable (\Vn).
0 = Messages controlled by S95, Wn and Vn (\V0). (Default)
1 = Single line connect message (\V1).
Bit 1 Reserved (0)
Bits 2-3 Error correction progress messages (Wn).
0 = DTE speed only (W0). (Default)
1 = Full reporting (W1).
2 = DCE (line) speed only (W2).
Bits 4-5 Caller ID (+VCID).
0 = Caller ID disabled (+VCID=0). (Default)
1 = Short (formatted) Caller ID enabled (+VCID=1).
2 = Long (unformatted) Caller ID enabled (+VCID=2).
Bits 6-7 Reserved (Default = 11b).
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
41
Chapter 4 - V.22bis Commands
S36 - LAPM Failure Control
Default: 7 (00000111b)
Bits 0-2 This value indicates what should happen upon a LAPM failure. These fallback options are initiated
immediately upon connection if S48=128. If an invalid number is entered, the number is accepted into the register,
but S36 will act as if the default value has been entered.
0 = Modem disconnects.
1 = Modem stays on-line and a Direct mode connection is established.
2 = Reserved.
3 = Modem stays on-line and a Normal mode connection is established.
4 = An MNP connection is attempted and if it fails, the modem disconnects.
5 = An MNP connection is attempted and if it fails, a Direct mode connection is established.
6 = Reserved.
7 = An MNP connection is attempted and if it fails, a Normal mode connection is established. (Default)
Bits 3-7 Reserved
S37 - Desired Line Connection Speed
S37 specifies the desired line connection speed.
Default: 0
Bits 0-3 Desired line connection speed. This is linked with the Fn command. If an invalid number is entered, the
number is accepted into the register, but S37 will act as if the default value has been entered.
0 = Attempt automode connection (F0). (Default.)
1-3 = Attempt to connect at 300 bps (F1).
4 = Reserved.
5 = Attempt to connect at V.22 1200 bps (F4).
6 = Attempt to connect at V.22bis 2400 bps (F5).
7 = Attempt to connect at V.23 (F3).
Bits 4-7 Reserved
S38 - Delay Before Forced Hang Up
S38 specifies the delay between the modem's receipt of the H command to disconnect (or ON-to-OFF transition of
DTR if the modem is programmed to follow the signal), and the disconnect operation. Applicable to error-correction
connection only. This parameter can be used to ensure that data in the modem buffer is sent before the modem
disconnects.
1. If S38 is set to a value between 0 and 254, the modem will wait that number of seconds for the remote modem to
acknowledge all data in the modem buffer before disconnecting. If time expires before all data is sent, the NO
CARRIER result code will be issued to indicate that data has been lost. If all data is transmitted prior to time-out,
the response to the H0 command will be OK.
2. If S38 is set to 255, the modem does not time-out and continues to attempt to deliver data in the buffer until the
connection is lost or the data is delivered.
Range: 0-255 seconds
Default: 20
S39 - Flow Control Bit Mapped Options Status
Default: 3 (00000011b)
Bits 0-2 Status of command options.
0 = No flow control.
3 = RTS/CTS (&K3). (Default)
4 = XON/XOFF (&K4).
5 = Transparent XON (&K5).
6 = Both methods (&K6).
Bits 3-7 Reserved.
S40 - General Bit Mapped Options Status
S40 indicates the status of command options.
Default: 104 (68h) (01101000b)
Bits 0-2 Reserved.
Bits 3-5 Break Handling (\Kn).
0 = \K0.
1 = \K1.
2 = \K2.
3 = \K3.
4 = \K4.
5 = \K5. (Default)
Bits 6-7 Reserved.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
42
Chapter 4 - V.22bis Commands
S41 - General Bit Mapped Options Status
S41 indicates the status of command options.
Default: 13 (C3h) (00001101b)
Bits 0-1 Compression selection (%Cn).
0 = Disabled (%C0).
1 = MNP 5 (%C1).
2 = V.42 bis (%C2).
3 = MNP 5 and V.42 bis (%C3). (Default)
Bits 2 Auto retrain (%En).
0 = Retrain disabled (%E0).
1 = Retrain enabled (%E1). (Default)
Bit 3-7 Reserved.
S48 - V.42 Negotiation Action
The V.42 negotiation process determines the capabilities of the remote modem. However, when the capabilities of
the remote modem are known and negotiation is unnecessary, this process can be bypassed if so desired.
Range: 0, 7, or 128 If an invalid number is entered, it is accepted into the S-Register, but S48 will act as if 128 has
been entered.
Default: 7
S48=0
S48=7
Disable negotiation; bypass the detection and negotiation phases; and proceed with LAPM.
Enable negotiation. (Default.)
S48=128 Disable negotiation; bypass the detection and negotiation phases; and proceed at once with the fallback
action specified in S36. Can be used to force MNP.
S82 - Break Handling Options
Break Signals provide a way for the user to get the attention of the remote modem. The break type depends on the
speed application. LAPM specifies three methods of break signal handling; in sequence, expedited, and destructive,
If an in number is entered, it is accepted into the S register, but S82 will act as if the default value has been entered.
Range: 3,7, or 128
Default: 128
S82 = 3 Expedited: Modem sends a break immediately; data integrity is maintained ahead of and after the break.
S82 = 7 Destructive: Modem sends a break immediately; data being processed by each modem at the time of the
break is destroyed.
S82 =128 In sequence: Modem sends a break in sequence with any transmitted data; data integrity is maintained
both ahead of and after the break (default)
S86 - Call Failure Reason Code
When the modem issues a NO CARRIER result code, a value is written to S86 Register to help determine the reason
for the failed connection. S86 records the first event that contributes to a NO CARRIER message. Code definitions are:
Range: 0-26
Default: 21
S86=0 Normal hangup, no error occurred.
S86=1 Reserved.
S86=2 Reserved.
S86=3 Call Waiting caused disconnect.
S86=4 Physical carrier loss.
S86=5 No error correction at the other end.
S86=6 No response to feature negotiation.
S86=7 This modem is async only; the other modem is sync only.
S86=8 No framing technique in common.
S86=9 No protocol in common.
S86=10 Bad response to feature negotiation.
S86=11 No sync information from the remote modem.
S86=12 Normal hangup initiated by the remote modem.
S86=13 Retransmission limit reached.
S86=14 Protocol violation occurred.
S86=15 Lost DTR.
S86=16 Received GSTN cleardown.
S86=17 Inactivity timeout.
S86=18 Speed not supported.
S86=19 Long space disconnect.
S86=20 Key abort disconnect.
S86=21 Clears previous disconnect reason.
S86=22 No connection established.
S86=23 Disconnect after three retrains.
S86=24 Call Waiting tone detected.
S86=25 Extension Pickup detected.
S86=26 Remote Hangup detected.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
43
Chapter 4 - V.22bis Commands
S91 – PSTN Transmit Attenuation Level
S91 sets transmit attenuation level from 0 to 15 dBm for the PSTN mode, resulting in a transmit level from 0 to -15
dBm.
Range: 0 to 15 dBm (Corresponding to 0 to -15 dBm transmit level.)
Default: 10 (-10 dBm transmit level.)
S95 - Extended Result Codes Control
A bit set to a 1 in this parameter, in conjunction with the W command, will enable the corresponding extended result
code.
The W command determines the corresponding actual result code reporting (see W command).
Default: 0
Bit 0
Bit 1
CONNECT result code indicates DCE speed instead of DTE speed.
Append/ARQ to CONNECT XXXX result code in error-correction mode (XXXX = rate).
Bit 2-7 Reserved.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
44
Chapter 4 - V.22bis Commands
V.22bis Result Codes
The modem responds to commands from the DTE and to activity on the line by signaling to the DTE in the form of
result codes. .
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. The long-form results codes can be modified by
the OEM through the .INF file.
Table of Result Code Definitions
Code
0
1
Message
OK
CONNECT
Meaning
A command line has been executed.
For X command values specifying no speed reporting, the modem has connected
to the line and either the line speed is 300 bps and line speed is enabled, or the
DTE speed is 300 bps and DTE speed reporting is enabled.
An incoming ring signal is detected on the line. What qualifies as a ring signal is
determined by country-dependent parameters, modifiable through patch code.
Sent when attempting to establish a call if:
2
3
RING
NO CARRIER
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.
Also sent when the modem auto-disconnects due to loss of carrier.
For X0, sent for the following conditions:
1. If busy tone detection is enforced, busy or circuit busy has been detected.
2. If dial tone detection is enforced or selected, dial tone has not been detected.
Sent during an attempt to execute a command line if any of the following conditions
occur:
1. The command line contains a syntax error.
2. The modem cannot execute a command contained in the command line, i.e.,
the command does not exist or is not supported.
3. A command parameter within the command line is outside the permitted range.
For X0, X1, X2, and X3, this message is sent instead of DELAYED and
BLACKLISTED.
The modem has connected to the line and either the line speed is 1200 bps and
DCE speed reporting is enabled, or the DTE speed is 1200 bps and DTE speed
reporting is enabled.
4
5
ERROR
CONNECT 1200
6
NO DIAL TONE
BUSY
For X2 and X4, the modem has been instructed to wait for dial tone during dialing
but none is received.
7
For X3 and X4, if busy tone detection is enforced, the busy (engaged) signal is
detected on the line when the modem is attempting to originate a call.
The modem is attempting to originate a call if a continuous ringback signal is
detected on the line until the expiration of the timer S7.
The modem has connected to the line, the DTE speed is 600 bps, and DTE speed
reporting is enabled.
The modem has connected to the line and either the line speed is 2400 bps and
DCE speed reporting is enabled, or the DTE speed is 2400 bps and DTE speed
reporting is enabled.
8
NO ANSWER
CONNECT 600
CONNECT 2400
9
10
11
12
13
14
15
CONNECT 4800
CONNECT 9600
CONNECT 7200
CONNECT 12000
CONNECT 14400
The modem has connected to the line, the DTE speed is 4800 bps and DTE speed
reporting is enabled.
The modem has connected to the line, the DTE speed is 9600 bps and DTE speed
reporting is enabled.
The modem has connected to the line, the DTE speed is 7200 bps and DTE speed
reporting is enabled.
The modem has connected to the line the DTE speed is 12000 bps and DTE speed
reporting is enabled.
The modem has connected to the line, the DTE speed is 14400 bps and DTE
speed reporting is enabled.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
45
Chapter 4 - V.22bis Commands
Code
Message
Meaning
16
CONNECT 19200
The modem has connected to the line, the DTE speed is 19200 bps and DTE
speed reporting is enabled.
22
CONNECT
75TX/1200RX
CONNECT
1200TX/75RX
DELAYED
The modem has established a V.23 originate connection and line speed reporting
is enabled.
The modem has established a V.23 answer connection and line speed reporting is
enabled.
For X4, sent when a call fails to connect and the number dialed is considered
'delayed' due to country blacklisting requirements.
For X4, sent when a call fails to connect and the number dialed is considered
'blacklisted'.
23
24
32
BLACKLISTED
59
CONNECT 16800
CONNECT 21600
CONNECT 24000
CONNECT 26400
CONNECT 28800
LINE IN USE
The modem has connected to the line, the DTE speed is 16800 bps and DTE
speed reporting is enabled.
The modem has connected to the line, the DTE speed is 21600 bps and DTE
speed reporting is enabled.
The modem has connected to the line, the DTE speed is 24000 bps and DTE
speed reporting is enabled.
The modem has connected to the line, the DTE speed is 26400 bps and DTE
speed reporting is enabled.
The modem has connected to the line, the DTE speed is 28800 bps and DTE
speed reporting is enabled.
The modem attempted to go off-hook when an extension was already occupying
the line.
61
62
63
64
83
84
CONNECT 33600
CONNECT 31200
The modem has connected to the line, the DTE speed is 33600 bps and the DTE
speed reporting is enabled.
The modem has connected to the line DTE speed is 31200 bps and the modem is
to report the DTE speed upon connecting.
91
Notes:
1. See Vn for result code selection, i.e., short form (result code) or verbose/extended (result message).
2. See Wn for extended connect message control.
3. See S95 for extended result code enabling options (which override some Wn commands).
4. See Xn for extended result code subset enabling options.
5. See \Vn for single line connect message enable options.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
46
Appendix A – Test/Demo Card Information
Appendix A – Test/Demo Card
Information
Block Diagram
Power
Switch
Power
Supply
Power
Connector
Volume
Control
Speaker
DS1
Modem
Module
DB-25
RS-232
Transceiver
(RS-232)
RJ-11
Connector
Tip/Ring
Fuse
Figure A–1. Serial Test/Demo Board Block Diagram
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
47
Appendix B – Product Approvals, Regulatory Design Considerations, Compliance
Appendix B - Product Approvals,
Compliance, and Layout
Considerations
Product Safety and EMC Approvals
Safety
EMC
UL 60950
CSA 950
EN 60950
AS 3260
FCC Part 15 (Class B)
Canada (Class B)
EN 55022 (Class B)
EN 55024
Country Certifications
While this device can be configured for specific country operation, doing so DOES NOT constitute country
approval. This modem is not approved in or configured for operation in all countries. The following list is displays
the country approvals as of April 1, 2003.
This information can be deemed reliable, but is not guaranteed. All information is subject to change.
Contact your Multi-Tech Systems, Inc. sales representative or call the world headquarters at 800-328-9717.
Country
US
Canada
Austria
Belgium
Cyprus
Denmark
Finland
France
Germany
Greece
Iceland
Ireland
Country Code
B5
B5
B5
B5
B5
B5
B5
B5
B5
B5
B5
B5
B5
B5
B5
B5
B5
B5
B5
B5
B5
B5
Italy
Liechtenstein
Luxembourg
Netherlands
Norway
Portugal
Spain
Sweden
Switzerland
UK
More planned.
Note: See the AT+GCI command. Reporting uses of this command will show you the current country code and
the country profiles stored in the modem’s ROM.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
48
Appendix B – Product Approvals, Regulatory Design Considerations, Compliance
Regulatory Design Considerations
This section discusses hardware considerations, safety, and Telecom labeling requirements.
Hardware Considerations
Disclaimer: Multi-Tech Systems makes no warranty claims for vendor product recommendations listed below.
Other vendor products may or may not operate satisfactorily. Multi-Tech System’s recommended vendor
products only indicate that the product has been tested in controlled conditions and were found to perform
satisfactorily.
Figure B–1. Recommended Main Board Filtering
Surface mount ferrites are used on T&R (Tip and Ring) to mitigate emission levels out the RJ-11 cable. 220pF
capacitors are also used on T&R to reduce the common mode emissions that may be present in certain systems.
The ferrite and capacitors also aid in reducing the effects of transients that may be present on the line.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
49
Appendix B – Product Approvals, Regulatory Design Considerations, Compliance
Recommended Ferrite (SMT)
Manufacturer – Associated Component Technology (ACT) – Part # - YCB-1206
Manufacturer – Murata Erie – Part # - BLM31A601SPT
Recommended Ferrite (Thru-Hole)
Manufacturer – Associated Component Technology (ACT) – Part # - WB2-2.OT
Recommended Capacitor
Manufacturer – Murata Erie – Part # - GHM3045X7R221K-GC (Surface mount device) and
Part # - DE0807B221K-KH (Thru-hole device)
Manufacturer – Ever Grace Electronic Industrials -- Part # - YP221K2EA7PS
Note: The capacitors used on T&R must have a Y2 safety rating.
Recommended Connector
Manufacturer – Stewart – Part # - SS-6446-NF-A431
Recommended Fuse
Manufacturer – RayChem – Part # - TR600-150
Note: The fuse is also needed to meet UL1950 3rd edition protection against over-voltage from power line
crosses.
Common Mode Choke
Manufacturer – TDK – Part # - ZJYS51R5-2PT
Recommended Sidactor
Manufacturer – Teccor Electronics – Part # - P#3100SA
Manufacturer – ST Microelectronics -- Part 1 – SMP100-270
Recommended Transceiver
Manufacturer – Analog Devices – Part # - ADM207EAR
Safety
All creepages and clearances for the MT2456SMI have been designed to meet requirements of safety standards
EN 60950. The requirements are based on a working voltage of 250V. When the recommended DAA circuit
interface is implemented in a third party design all creepage and clearance requirements must be strictly adhered
to. The third party safety design must be evaluated by the appropriate national agency per the required
specification.
User accessible areas: Based on where the third party design is to be marketed/sold or used, it may be
necessary to provide an insulating cover over all TNV exposed areas. Consult with the recognized safety agency
to determine the requirements.
Notice: Even if the recommended design considerations are followed, there are no guarantees that a particular
system will comply with all the necessary regulatory requirements. It is imperative that specific designs be
completely evaluated by a qualified/recognized agency.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
50
Appendix B – Product Approvals, Regulatory Design Considerations, Compliance
SocketModem Placement
This figure illustrates where to place the SocketModem on a typical application. It must be placed so that the
analog end is near the phone jack.
0.035 [0.889] Drill with 0.060 [1.524] Pad
.0787 TYP
[2]
0.125 [3.175] Non-Plated
Analog to Digital Barrier
(Shown for Reference Only)
1.732
[44]
.750
[19.05]
.145
[3.683]
.945
[24.003]
B or C
Note: The locking end of C should
go in the Motherboard.
E (Digital)
F
G
Note: The modem should be placed with the
analog pins as close as possbile to the line jack.
D (Power and GND)
A
D (Analog)
Figure B–3. SocketModem Placement
Note: The dimensions in this diagram are examples only.
See the mechanical drawing in Chapter 2 for true dimensions.
Key
Qty
1
Ref
A
Name
Reference
Description
Generic Motherboard
1
1
2
2
B (or C)
C (or B)
D
E
F
Recommended
Recommended
Recommended
Recommended
Reference
RICHCO DLMSPM-4-01 Support Post (L=.250”)
RICHCO MSPM-4-01 Support Post (L=.250”)
Singatron Enterprises 1211-04-S-01-B)
Singatron Enterprises 1211-10-S-01-B)
ModemModule Assembly
1
1
G
Reference
Line Jack
Note: The analog to digital barrier is really a safety isolation barrier between TNV and SELV.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
51
Appendix B – Product Approvals, Regulatory Design Considerations, Compliance
Compliance
Multi-Tech Systems, Inc. Compliance
This section discusses Multi-Tech’s SocketModem compliance with 47 CFR Part 68 and Industry Canada CS-03
Telecom regulations.
Telecom Requirements for the United States
FCC Part 15 Regulation
This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to Part
15 of the FCC rules. These limits are designed to provide reasonable protection against harmful interference in a
residential installation. This equipment generates, uses, and can radiate radio frequency energy, and if not
installed and used in accordance with the instructions, may cause harmful interference to radio communications.
However, there is no guarantee that interference will not occur in a particular installation. If this equipment does
cause harmful interference to radio or television reception, which can be determined by turning the equipment off
and on, the user is encouraged to try to correct the interference by one or more of the following measures:
Reorient or relocate the receiving antenna.
Increase the separation between the equipment and receiver.
Plug the equipment into an outlet on a circuit different from that to which the receiver is connected.
Consult the dealer or an experienced radio/TV technician for help.
This device complies with Part 15 of the FCC rules. Operation of this device is subject to the following conditions:
(1) This device may not cause harmful interference, and (2) this device must accept any interference that may
cause undesired operation.
WARNING – Changes or modifications to this unit not expressly approved by the party responsible for
compliance could void the user’s authority to operate the equipment.
47 CFR Part 68 Telecom
1. This equipment complies with Part 68 of the FCC rules and the requirements adopted by the ACTA. Located
on this equipment is a label that contains, among other information, the FCC registration number and ringer
equivalence number (REN) for this equipment or a product identifier in the format US:AAAEQ##TXXXX. If
requested, this number must be provided to the telephone company.
2. A plug and jack used to connect this equipment to the premises wiring and telephone network must comply
with the applicable FCC Part 68 rules and requirements adopted by the ACTA. It’s designed to be connected
to a compatible modular jack that is also compliant.
3. The ringer equivalence number (REN) is used to determine the number of devices that may be connected to
a telephone line. Excessive RENs on a telephone line may result in the devices not ringing in response to an
incoming call. In most but not all areas, the sum of RENs should not exceed five (5.0). To be certain of the
number of devices that may be connected to a line, as determined by the total RENs, contact the local
telephone company. For products approved after July 23, 2001, the REN for this product is part of the
product identifier that has the format US:AAAEQ##TXXXX. The digits represented by ## are the REN
without a decimal point (e.g., 03 is a REN of 0.3). For earlier products, the REN is separately shown on the
label.
4. If this equipment causes harm to the telephone network, the telephone company will notify you in advance
that temporary discontinuance of service may be required. But if advance notice isn't practical, the telephone
company will notify the customer as soon as possible. Also, you will be advised of your right to file a
complaint with the FCC if you believe it is necessary.
5. The telephone company may make changes in its facilities, equipment, operations or procedures that could
affect the operation of the equipment. If this happens, the telephone company will provide advance notice in
order for you to make necessary modifications to maintain uninterrupted service.
6. If trouble is experienced with this equipment, please contact Multi-Tech Systems, Inc. at the address shown
below for details of how to have the repairs made. If the equipment is causing harm to the telephone
network, the telephone company may request that you disconnect the equipment until the problem is
resolved.
7. Connection to party line service is subject to state tariffs. Contact the state public utility commission, public
service commission or corporation commission for information.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
52
Appendix B – Product Approvals, Regulatory Design Considerations, Compliance
8. No repairs are to be made by you. Repairs are to be made only by Multi-Tech Systems or its licensees.
Unauthorized repairs void registration and warranty.
9. If your home has specially wired alarm equipment connected to the telephone line, ensure the installation of
this equipment does not disable your alarm equipment.
If you have questions about what will disable alarm equipment, consult your telephone company or a
qualified installer.
10. Connection to party line service is subject to state tariffs. Contact the state public utility commission, public
service commission or corporation commission for information.
11. This equipment is hearing aid compatible.
12. Manufacturing Information:
Manufacturer:
Trade Name
Multi-Tech Systems, Inc.
SocketModem
Model Number:
Registration No:
Ringer Equivalence:
Modular Jack (USOC):
Service Center in USA:
MT2456SMI-22
US: AU7MD04B2456
0.4B
RJ11C or RJ11W (single line)
Multi-Tech Systems, Inc.
2205 Woodale Drive
Mounds View, MN 55112
U.S.A.
(763) 785-3500
(763) 785-9874 Fax
Label Content and Format
Approved terminal equipment and approved protective circuitry shall prominently display the following information
using the format shown below:
S
S
S
S
S
S
Responsible party
Product Identification
Equipment Code
Ringer Equivalence
Ringer Type
Indication that the product meets the requirements of 47 CFR Part 68
The information required by the first five items shall correspond to the records in the ACTA database of approved
equipment. The required information shall be encoded in the following format:
US: AAAEQ##TXXX
Where:
US: Is a fixed field that indicates the equipment meets all requirements of 47 CFR Part 68 (including the
requirements published by ACTA).
AAA is the responsible party’s Grantee Code obtained previously from the FCC’s Common Carrier Bureau or
currently from ACTA.
EQ Is an Equipment Code indicating to the Service Provider any special signal handling or billing requirements. The
Equipment codes are listed in Annex A (normative).
## Is the Ringer Equivalence Number without a decimal point (e.g. REN of 1.0 = 10, REN of 0.3 = 03). In the case of
a “Z” ringer, ZZ shall appear. In the case of approved equipment without a network interface and equipment not
connecting to circuits with analog ringing supplied then “NA” shall appear.
T is the ringer type letter associated with the Ringer Equivalence Number, in accordance with the technical
requirements. In the case of approved equipment without a network interface and equipment not connecting to
circuits with analog ringing supplied, the letter “N” shall appear.
XXX Is a product identifier, unique when combined with the responsible party’s Grantee Code, of at least one and up
to nine alphanumeric characters (including one or more dashes (-) if desired. A dash shall not appear as the first or
last character nor shall the identifier consist entirely of dashes). The responsible party shall define this identifier.
Label Physical Characteristics
The information required above shall be permanently affixed and legible without magnification. It may be etched,
engraved, stamped, indelibly printed or otherwise permanently marked. Alternatively, the required information may be
permanently marked on a nameplate of metal, plastic or other material fastened to the enclosure by welding, riveting
or with a permanent adhesive. Such a nameplate shall be able to last for the expected lifetime of the equipment and
shall not be readily detachable.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
53
Appendix B – Product Approvals, Regulatory Design Considerations, Compliance
Labeling Continuity and Changes
The labeling content and format requirements in effect when a product was approved shall be effective for the life of
the product. The labeling content and format requirements in effect at approval shall also continue to be effective for
modified products. However, the responsible party shall have the option of conforming a product's labeling to current
content and format requirements at any time.
Other Label Requirements
The label shall be placed in one of the following locations in a location where it can be found after installation:
S
S
S
on an outside surface
inside a readily available access door or panel
on another readily accessible surface
For example, the label should not be placed on the rear of a permanently wall-mounted device in a manner such that
it is not readily accessible.
Telecommunications Regulations for Canada
The following requirements are established under section 69.3 of the Telecommunications Act for purposes of section
5 of the Telecommunications Apparatus Regulations.
Registered equipment shall bear the following identifying marks, and the Declaring Party shall ensure that these
marks are permanently affixed to the equipment:
(a) The registration number — Specifications of this mark are given in the document: Self-Marking of the
Certification/Registration Number on Terminal Equipment — Application Procedure and Agreement; and
(b) The model identification number under which the product was registered.
A statement of compliance with Industry Canada requirements, such as the one given below, shall accompany each
unit of equipment whether registered under this procedure or previously certified:
"This product meets the applicable Industry Canada technical specifications"
For terminal equipment intended for connection to loop-start or ground-start interfaces, the Ringer Equivalence
Number (REN) must be calculated as per Section 1.8 of CS-03, Part I. A REN higher than that determined may be
assigned by manufacturers to allow for production variations. The REN must be marked on the terminal equipment
itself or added to the note below. A note similar to the following shall accompany each unit of equipment whether
registered under this procedure or previously certified:
"The Ringer Equivalence Number is an indication of the maximum number of devices allowed to be
connected to a telephone interface. The termination on an interface may consist of any combination of
devices subject only to the requirement that the sum of the RENs of all the devices does not exceed five".
Pursuant to section 69.3 of the Telecommunications Act, Certified or self-declared TE will bear a valid identifying
certification or registration number. The marking of the certification or registration number on the product shall be as
follows:
(a) TAC holder/DP will be responsible for permanently affixing the certification/registration number on the TE.
The certification/registration number (see example below) identifies Certified or self-declared TE to the
public, representatives of the telecommunications common carriers, the Department, and other interested
parties. The letter height must be no less than 1.5 mm and the letters must be legible without magnification.
(b) For integrated devices, e.g. a modem or one that is intended to become a sub-assembly of host equipment
e.g. a data terminal, computer etc. that are designed to interface directly with the network, the
certification/registration number shall be affixed to the integrated device itself.
(c) The certification/registration number for a packaged TE will denote that the total package has been
registered. However, the marking will normally be placed on that unit of the package which connects to the
network. e.g. in a PBX, the marking will be placed on the common equipment which connects to the
network, rather than on plug-in components which may be added later. The Terminal Equipment List will
show the common equipment but not the standard station apparatus or any proprietary station apparatus.
(d) The marking format of the certification/registration number is as follows:
IC: XXXXXX-YYYYYYYY
Where:
S
The letters "IC" have no other meaning or purpose than to identify the Industry Canada
certification/registration number, and
S
“XXXXXX-YYYYYYYY” is the certification/registration number; “XXXXXX” is the Company Number¹
(CN); it consists of up to six alphanumeric characters (A-Z, 0-9) assigned by Industry Canada; and
“YYYYYYYY” is the Unique Product Number (UPN); it consists of up to eight alphanumeric
characters (A-Z, 0-9) assigned by the applicant. Other characters, (such as & # *-) may not be
used. Alphabetic characters must be capitalized.
¹ Note: The Company Number of registered equipment ends with an alphabetic character.
(e) Certification Numbers granted prior to the implementation of the above marking format are grandfathered.
(i) For previously certified TE, the self-marking format shall consist of the old certification number preceded
by “IC:” For example, if the certification number is “123 1234 A”, then the self-mark would read “IC: 123
1234 A”.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
54
Appendix B – Product Approvals, Regulatory Design Considerations, Compliance
(ii) For a new model that is registered to a family of previously certified TE, the self-marking format shall be:
IC: XXXXXX-ZZZZZZZZ
Where:
S
S
“XXXXXX” is the Company Number, as in (d) above ; and
“ZZZZZZZZ” is either the old certification number minus the old company number, or a new Unique
Product Number assigned by the applicant. For example, if a new model is registered to the family of
products with certification number “123 1234 A”, and that the Company Number for the registration is
“123A”, then the self-mark for this new model would read “IC: 123A-1234 A”. If the applicant decides to
replace “1234 A” with a new UPN, say “5678", then the self-mark would read “IC: 123A-5678".
Industry Canada
This Class B digital apparatus meets all requirements of the Canadian Interference-Causing Equipment
Regulations.
Cet appareil numérique de la classe B respecte toutes les exigences du Reglement Canadien sur le matériel
brouilleur.
Multiple Listing
This terminal device may be multiple listed to other distributors based upon the approval granted to the original
certificate holder. In order to obtain a multiple listing certification, the following documentation must be presented
to Industry Canada:
(a) The model number, Industry Canada certificate number and certification number of the approved equipment;
(b) A letter from the original certificate holder authorizing the Department to use information on file to grant a
multiple listing certification. The name/model number, certificate number and certification number for the
subject equipment must be shown. The letter must also declare that the model to be multiple listed is
identical in design and construction to the originally approved model;
(c) A letter, from the proposed multiple listee, requesting the certification;
(d) A Terminal Equipment Certification / Testing Application and Agreement form, completed by the proposed
multiple listee;
(e) A drawing, sample or illustration of the product label; and
(f) Payment in accordance with TRC-49 section on Multiple Listings.
New Zealand Telecom Warning Notice
1. The grant of a Telepermit for any item of terminal equipment indicates only that Telecom has accepted that
the item complies with minimum conditions for connection to its network. It indicates no endorsement of the
product by Telecom, nor does it provide any sort of warranty. Above all, it provides no assurance that any
item will work correctly in all respects with another item of Telepermitted equipment of a different make or
model, nor does it imply that any product is compatible with all of Telecom’s network services.
This equipment is not capable under all operating conditions of correct operating conditions of correct
operation at the higher speed which it is designated. 33.6 kbps and 56 kbps connections are likely to be
restricted to lower bit rates when connected to some PSTN implementations. Telecom will accept no
responsibility should difficulties arise in such circumstances.
2. Immediately disconnect this equipment should it become physically damaged, and arrange for its disposal or
repair.
3. This modem shall not be used in any manner which could constitute a nuisance to other Telecom
customers.
4. This device is equipped with pulse dialing, while the Telecom standard is DTMF tone dialing. There is no
guarantee that Telecom lines will always continue to support pulse dialing.
Use of pulse dialing, when this equipment is connected to the same line as other equipment, may give rise
to 'bell tinkle' or noise and may also cause a false answer condition. Should such problems occur, the user
should NOT contact the Telecom Faults Service.
The preferred method of dialing is to use DTMF tones, as this is faster than pulse (decadic) dialing and is
readily available on almost all New Zealand telephone exchanges.
5. Warning Notice: No '111' or other calls can be made from this device during a mains power failure.
6. This equipment may not provide for the effective hand-over of a call to another device connected to the
same line.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
55
Appendix B – Product Approvals, Regulatory Design Considerations, Compliance
7. Some parameters required for compliance with Telecom’s Telepermit requirements are dependent on the
equipment (PC) associated with this device. The associated equipment shall be set to operate within the
following limits for compliance with Telecom’s Specifications:
For repeat calls to the same number:
S
There shall be no more than 10 call attempts to the same number within any 30 minute period for
any single manual call initiation, and
S
The equipment shall go on-hook for a period of not less than 30 seconds between the end of one
attempt and the beginning of the next attempt.
For automatic calls to different numbers:
S
The equipment shall be set to ensure that automatic calls to different numbers are spaced such
that there is no less than 5 seconds between the end of one call attempt and the beginning of
another.
8. For correct operation, total of the RN’s of all devices connected to a single line at any time should not
exceed 5.
International Modem Restrictions
Some dialing and answering defaults and restrictions may vary for international modems. Changing settings may
cause a modem to become non-compliant with national telecom requirements in specific countries. Also note
that some software packages may have features or lack restrictions that may cause the modem to become non-
compliant.
EMC, Safety, and R&TTE Directive Compliance
The CE mark is affixed to this product to confirm compliance with the following European Community Directives:
Council Directive 89/336/EEC of 3 May 1989 on the approximation of the laws of Member States
relating to electromagnetic compatibility;
and
Council Directive 73/23/EEC of 19 February 1973 on the harmonization of the laws of Member States
relating to electrical equipment designed for use within certain voltage limits;
and
Council Directive 1999/5/EC of 9 March on radio equipment and telecommunications terminal
equipment and the mutual recognition of their conformity.
South African Statement
This modem must be used in conjunction with an approved surge protection device.
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
56
Index
Index
$F – FastConnect Control, 33
%L - Report Line Signal Level, 24
%Q - Report Line Signal Quality, 24
&C - RLSD Option, 17
Specifications,Mechanical, 6
Specifications,Technical, 5
–STE= - Set Telephony Extension, 25
T - Set Tone Dial Default, 22
&D - DTR Option, 17
Table of Result Codes, 16
&F - Restore Factory Configuration (Profile), 14
&G - Select Guard Tone, 23
Technical Specifications, 5
-TRV – Tip and Ring Voltage Measurement, 34
&K - Flow Control, 17
&P - Select Pulse Dial Make/Break Ratio, 23
&R - RTS/CTS Option, 18
-TTE - Threshold Adjustments for Telephony Extension,
34
V.22bis Commands
&T - Local Analog Loopback Test, 14
&V - Display Current Configuration and Stored Profiles,
23
$F – FastConnect Control, 33
%L - Report Line Signal Level, 24
%Q - Report Line Signal Quality, 24
&C - RLSD Option, 17
** - Load to Internal RA, 14
*B - Display Blacklisted Numbers, 24, 25
+ESA - Configure Synchronous Access Submode, 31
+ESR - Selective Repeat, 29
+GCI - Country of Installation, 13
+IBC – In Band Commands, 19
+IFC - DTE-Modem Local Flow Control, 18
+MS - Modulation Selection, 27
+PCW - Call Waiting Enable, 26
+VCID - Caller ID (CID), 12
+VDR - Distinctive Ring, 26
+VRID - Report Retrieved Caller ID (CID), 12
A - Answer, 22
&D - DTR Option, 17
&F - Restore Factory Configuration (Profile), 14
&G - Select Guard Tone, 23
&K - Flow Control, 17
&P - Select Pulse Dial Make/Break Ratio, 23
&R - RTS/CTS Option, 18
&T - Local Analog Loopback Test, 14
&V - Display Current Configuration and Stored Profiles,
23
** - Load to Internal RA, 14
*B - Display Blacklisted Numbers, 24, 25
+ESA - Configure Synchronous Access Submode, 31
+ESR - Selective Repeat, 29
B - ITU-T or Bell, 28
B - Transmit Break to Remote, 29
Country Certifications, 48
D - Dial, 21
Design considerations
Vendor recommendations, 49
E - Command Echo, 15
Electrical Characteristics, 9
EMC, Safety, and R&TTE Directive Compliance, 56
FCC Regulations, 52
G - Modem-to-Modem Flow Control (XON/XOFF), 18
H - Disconnect (Hang-Up), 22
Handling Precautions, 9
+ETBM - Call Termination Buffer Management, 29
+GCI - Country of Installation, 13
+IBC – In Band Commands, 19
+IFC - DTE-Modem Local Flow Control, 18
+MS - Modulation Selection, 27
+PCW - Call Waiting Enable, 26
+VCID - Caller ID (CID), 12
+VDR - Distinctive Ring, 26
+VRID - Report Retrieved Caller ID (CID), 12
A - Answer, 22
B - ITU-T or Bell, 28
\B - Transmit Break to Remote, 29
Call Control Commands, 21
I - Identification, 13
International Modem Restrictions, 56
K - Break Control, 30
D - Dial, 21
E - Command Echo, 15
L - Speaker Volume, 22
FastConnect Command, 33
Mechanical Specifications, 6
Multi-Tech Systems, Inc. Compliance, 52
N - Operating Mode, 12
New Zealand Telecom Warning Notice, 55
O - Return to On-Line Data Mode, 22
P - Set Pulse Dial Default, 22
Physical Dimensions, 6
\G - Modem-to-Modem Flow Control (XON/XOFF), 18
Generic Modem Control, 12
H - Disconnect (Hang-Up), 22
I - Identification, 13
\K - Break Control, 30
L - Speaker Volume, 22
Line Side Device Commands, 34
M - Speaker Control, 23
Pin Configurations, 7
Placement, SocketModem, 51
Product Approvals, 48
Modulation Control Commands, 27
\N - Operating Mode, 12
Safety considerations, 50
Serial Demo Board block diagram, 47
South African Statement, Regulations, 56
O - Return to On-Line Data Mode, 22
P - Set Pulse Dial Default, 22
Q - Quiet Results Codes Control, 15
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
57
Index
–STE= - Set Telephony Extension, 25
Synchronous Access Mode Commands, 31
T - Set Tone Dial Default, 22
S25 - Delay To DTR Off, 40
S26 - RTS to CTS Delay, 40
S27 - Bit Mapped Options Status, 41
S28 - Bit Mapped Options Status, 41
S29 - Flash Dial Modifier Time, 41
S3 - Carriage Return Character, 37
S30 - Disconnect Inactivity Timer, 41
S31 - Bit Mapped Options Status, 41
S36 - LAPM Failure Control, 42
S37 - Desired Line Connection Speed, 42
S38 - Delay Before Forced Hang Up, 42
S39 - Flow Control Bit Mapped Options Status, 42
S4 - Line Feed Character, 37
Table of Result Codes, 16
Table of Supported V.80 Commands, 20
-TRV – Tip and Ring Voltage Measurement, 34
-TTE - Threshold Adjustments for Telephony Extension,
34
W - Connect Message Control, 15
X - Extended Result Codes, 16
Z - Soft Reset and Restore Profile, 12
V.22bis S-Parameters, 35
V.22bis S-Registers
Result Codes, 45
S0 - Number of Rings to Auto-Answer, 37
S1 - Ring Counter, 37
S10 - Lost Carrier To Hang Up Delay, 38
S11 - DTMF Tone Duration, 38
S12 - Escape Prompt Delay (EPD), 38
S14 - General Bit Mapped Options Status, 38
S16 - Test Mode Bit Mapped Options Status, 39
S19 - Reserved, 39
S2 - Escape Character, 37
S20 - Reserved, 39
S21 - V.24/General Bit Mapped Options Status, 39
S22 - Speaker/Results Bit Mapped Options Status, 40
S23 - General Bit Mapped Options Status, 40
S24 - Sleep Inactivity Timer, 40
S40 - General Bit Mapped Options Status, 42
S41 - General Bit Mapped Options Status, 43
S48 - V.42 Negotiation Action, 43
S5 - Backspace Character, 37
S7 - Wait Time for Carrier, Silence, or Dial Tone, 37
S8 - Pause Time For Dial Delay, 38
S82 - Break Handling Options, 43
S86 - Call Failure Reason Code, 43, 44
S9 - Carrier Detect Response Time, 38
S95 - Extended Result Codes Control, 44
Summary of S-Parameter Defaults, 36
Summary of S-Parameter Definitions, 37
W - Connect Message Control, 15
X - Extended Result Codes, 16
Z, 12
Multi-Tech Systems, Inc. MT2456SMI-22 SocketModem Developer’s Guide
58
|