US Robotics Mobile Communications                           Customer Support
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                           AT Command Set Reference
 Document Title :  Rockwell V.32/V.32bis AT Command Set Reference
  Revision Date :  27 Dec 95       See Also :  Technical Bulletin 3008
  Product Scope :  XJ3144, CC6144, XJ2144, XJ1144, CC3144, CC4144, XJEM1144,
                   CCEM1144, EM1144, XJ196FM, CC396FM, XJ124FM, CC324FM,
                   P2144 (9V), P296FMV (9V), A2144, AR196FM
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 1.0    Basic AT Commands 

 2.0    AT& Commands 

 3.0    AT% Commands

 4.0    AT\ Commands 

 5.0    Error Detection And Data Compression Commands

 6.0    MNP 10 Commands 

 7.0    S REGISTER SUMMARY

 8.0    XJ3144 and CC6144 Commands

 9.0    S Register Definitions

10.0    AT Command Result Codes
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1.0      Basic AT Commands

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TOP OF PAGE

The modem will respond to the commands detailed below.  Parameters applicable
to each command are listed with the command description.  The defaults shown
for each configuration are those used in the Rockwell stored profile 0.


A/      Repeat Last Command

The modem behaves as though the last command line had been re-sent by the
DTE.  "A/" will repeat all the commands in the command buffer. The principle
application of this command is to place another call (using the Dial command)
that failed to connect due to a busy line or no answer. This command must
appear alone on a command line and must be terminated by the "/" character.
This command should not be terminated by a carriage return.


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 +FCLASS command and country
specific requirements.
If +FCLASS=0 is selected, 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.
If +FCLASS=1 or 2 is selected, the modem will go off-hook in V.21 answer
mode.  It will generate the V.21 2100 Hz answer tone for 3 ± 0.5 seconds and,
following a delay of 70 mS, will proceed as if the +FTH=3 command were
issued.  At any stage up to (but excluding) the +FTH=3 command state, any
character will abort the communication. (See the description of the +FTH
command for details)


Bn      CCITT or Bell Modulation

When the modem is configured to allow either option, the modem will select
Bell or CCITT modulation for a line speed connection of 300 or 1200 bps
according to the parameter supplied.  Any other line speed will use a CCITT 
modulation standard.  The parameter value, if valid, is written to S27 
bit 6 (Also, see ATFn command).

    B0  Selects CCITT operation at 300 or 1200 bps during Call Establishment
    and a subsequent connection. (default for W-class models)

    B1  Selects BELL operation at 300 or 1200 bps during Call Establishment
    and a subsequent connection. (default for US models)

        
Dn      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 handshake in originate mode.
In W-class models, the action of going off-hook is affected by the status of
the Line Current Sense input, if the line current sensing is enabled, and by
the blacklist and delayed list.  NOTE: If the ATD command is issued before
the S1 register has cleared, the modem will respond with the NO CONNECT
result code.

If +FCLASS=0 is selected, 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 in progress upon receipt of any DTE character before
completion of the handshake.

If +FCLASS=1 or 2 is selected, the modem will behave as a facsimile modem and
attempt to connect to a facsimile machine (or modem) by entering the HDLC
V.21 channel 2 receive state (as if +FRH=3 had been issued).  This command
will be aborted upon receipt of any DTE character if the modem has not
finished dialing.  In this case, the modem will go on-hook and return to
command mode after displaying the NO CARRIER message.  If the modem has
finished dialing, it proceeds as if the +FRH=3 command has been issued (Refer
to the +FRH command to determine how the modem behaves following this stage).
The valid dial string parameters are described below.  Punctuation characters
may be used for clarity, with parentheses, hyphen, and spaces being ignored.

    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.
    
    J       Perform MNP 10 link negotiation at the highest supported speed
            for this call only.
    
    K       Enable power level adjustment during MNP 10 link negotiation for
            this call only.
    
    L       Re-dial last number:  The modem will re-dial the last valid
            telephone number.  This command must be immediately after the "D"
                with all the following characters ignored.
    
    P       Select pulse dialing:  Pulse dial the numbers that follow until a
            "T" is encountered.  Affects current and subsequent dialing. T
            Select tone dialing:  Tone dial the numbers that follow until a
            "P" is encountered.  Affects current and subsequent dialing.
    
    R       This command will cause the modem to wait 10 seconds after
            dialing then go into answer mode.  This command must be placed at
            the end of the dial string.
    
    S=n     Dial the number stored in the directory (n = 0 to 19). (See &Z)
    
    !       Flash.  The modem will go on-hook for a time defined by the value
            of S29.
    
    W       Wait for dial tone:  The modem will wait for a dial tone before
            dialing the digits following "W".  If no dial tone is detected
            within the time specified by S6, the modem will abort the rest of
            the sequence, return on-hook, and generate an error message.
    
    @       Wait for silence:  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.
    
    ,       Dial pause:  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.
    
    ^       Enable calling tone:  Applicable to current dial attempt only.
            The calling tone is a 1800 Hz tone every 3-4 seconds that alerts
            recipient of automatic calling equipment (as defined in CCITT
            V.25).
    
    >       If enabled by country specific parameter, the modem will generate
            a grounding pulse on the EARTH relay output.
            

En      Command Echo

The modem enables or disables the echo of characters to the DTE according to
the parameter supplied. The parameter value, if valid, is written to S14 bit1.

    E0  Disables command echo.    
    E1  Enables command echo.  Default.

Fn      Select Line Modulation

   This command selects the line modulation according to the parameter
   supplied.  The line modulation is fixed unless automode is selected.
   This command interacts with the S37 and the "N" command.  The parameter 
   value, if valid, is written to S37 bit 0-3.  To select line modulation, 
   it is recommended that either the "F" command, or a combination of the 
   S37 and the "N" command, be used, but not both.

    F0      Selects auto-detect mode.  Sets N1 and sets S31 bit 1.  In this
            mode, the modem configures for auto mode operation.  All connect
            speeds are possible according the remote modem's preference.  The
            contents of S37 are ignored as is the sensed DTE speed.   Default
    
    F1      Selects V.21 or Bell 103 according to the "B" setting as the only
            acceptable line speed resulting in a subsequent connection.  Sets
            N0, sets S37 to 1, and clears S31 bit 1.  This command is
            equivalent to the command string: ATN0S37=1.
    
    F2      Not supported (other products use this setting for 600 bps).
    
    F3      Selects V.23 as the only acceptable line modulation for a
            subsequent connection.  Originator is at 75 bps and answerer is
            at 1200 bps.  Sets N0, sets S37 to 7, and clears S31 bit 1. This
            command is equivalent to the command string: ATN0S37=7.
    
    F4      Selects V.22 1200 bps or Bell 212A according to the "B" command
            setting as the only acceptable line speed for a subsequent
            connection.  Sets N0, sets S37 to 5, and clears S31 bit 1.  This
            command is equivalent to the command string:  ATN0S37=5.
    
    F5      Selects V.22bis as the only acceptable line modulation for a
            subsequent connection.  Sets N0, sets S37 to 6, and clears S31
            bit 1.  This command is equivalent to the command string:
            ATN0S37=6.
    
    F6      Select V.32bis 4800 bps or V.32 4800 bps as the only acceptable
            line modulation for a subsequent connection.  Sets N0, sets S37
            to 8, and clears S31 bit 1.  This command is equivalent to the
            command string:  ATN0S37=8.
    
    F7      Selects V.32bis 7200 bps as the only acceptable line modulation
            for a subsequent connection.  Sets N0, sets S37 to 12, and clears
            S31 bit 1.  This command is equivalent to the command string:
            ATN0S37=12.
    
    F8      Selects V.32bis 9600 bps or V.32 9600 bps as the only acceptable
            line modulation for a subsequent connection.  Sets N0, sets S37
            to 9, and clears S31 bit 1.  This command is equivalent to the
            command string:  ATN0S37=9.
    
    F9      Selects V.32bis 12000 bps as the only acceptable line modulation
            for a subsequent connection.  Sets N0, sets S37 to 10, and clears
            S31 bit 1.  This command is equivalent to the command string:
            ATN0S37=10.
    
    F10     Selects V.32bis 14400 bps as the only acceptable line modulation
            for a subsequent connection.  Sets N0, sets S37 to 11, and clears
            S31 bit 1.  This command is equivalent to the command string:
            ATN0S37=11.
            
Hn      Disconnect (Hangup)

This command initiates a hang up sequence.  This command may not be
available for some countries due to PTT restrictions.

    H0  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.
    H1  If on-hook, the modem will go off-hook and enter command mode.  The
        modem will return on-hook after a period of time determined by S7.

In      Identification

    The modem reports to the DTE the requested result according to the command
    parameter.    

    I0  Reports product code.
    I1  Reports pre-computed checksum from ROM.
    I2  The modem will respond OK.    
    I3  Reports firmware revision.
    I4  Reports modem identifier string.      Mfr=MEGAHERTZ        CmdSet=MHZR
        Mod=V.32bis        Fax=1, 2        ErrC=V.42bis, MNP5, MNP10
    I5  Reports Country Code parameter (e.g., "022").
    I6  Reports modem data pump model and internal code revision

Ln      Speaker Volume

The modem sets the speaker volume control according to the parameter
supplied.  The parameter value, if valid, is written to S22 bits 0 and 1.

    L0  Low speaker volume (Not supported defaults to medium).
    L1  Low speaker volume (Not supported defaults to medium).
    L2  Medium speaker volume  Default.
    L3  High speaker volume (Not supported defaults to medium).

Mn      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.    

    M0  Speaker is always off.
    M1  Speaker is on during call establishment, but off when receiving
        carrier.  Default    M2  Speaker is always on.
    M3  Speaker is off when receiving carrier and during dialing, but on
        during answering.

Nn      Automode Enable

This command enables or disables automode detection.  The parameter value, if
valid, is written to S31 bit 1.

    N0  Automode detection is disabled.  A subsequent handshake will be
        conducted according to the contents of S37 or, if S37 is 0, according
        to the most recently sensed DTE speed.
    N1  Automode detection is enabled.  A subsequent handshake will be
        conducted according to the automode algorithm supported by the modem.
        This command is equivalent to F0.  Default

On      Return to On-Line Data Mode:

This command determines how the modem will enter the on-line data mode.  If
the modem is in the on-line command mode, it enters the on-line data mode
with or without a retrain.  If the modem is in the off-line command mode (no
connection), ERROR is reported.

    O0  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 (+++).
    O1  Enters on-line data mode with a retrain before returning to on-line
        data mode.

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 mode for that particular call (e.g.,
ATDT...), this command is overridden so that all future dialing will be tone
dialed.

Qn      Quiet Results Codes Control

This command enables or disables the sending of result codes to the DTE
according to the parameter supplied.  The parameter value, if valid, is
written to S14 bit 2.    

    Q0  Enables result codes to the DTE.  Default.
    Q1  Disables result codes to the DTE.

Sn      Read/Write S Registers:

The modem selects an S Register, performs an S Register read or write
function, or reports the value of an S Register.
    n=v     Sets S Register "n" to the value "v".
    n?      Reports the value of S Register "n".  The parameter "n" can be
            omitted, in which case S0 will be assumed.  The "S" can be
            omitted in which case the last S Register accessed (default
            register) will be assumed.

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 Register bit to indicate that
all subsequent dialing should be conducted in tone mode.  Note that the "DP"
command will override this command.  Clears S14 bit 5. This command may not
be permitted in some countries.

Vn      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.

    V0  Enables short-form (terse) result codes.  Line feed is not issued
        before a short-form result code.
    V1  Enables long-form (verbose) result codes.  Default

Wn      Error Correction Message Control

This command controls the format of CONNECT messages.  The parameter value,
if valid, is written to S31 bits 2 and 3. (Also, see S95 description)

    W0  Upon connection, the modem reports only the DTE speed (e.g, CONNECT
        9600).  Subsequent responses are disabled.  Default
    W1  Upon connection, the modem reports the line speed, the error
        correction protocol, and the DTE speed, respectively.  Subsequent
        responses are disabled.
    W2  Upon connection, the modem reports the DCE speed (e.g, CONNECT 2400).
        Subsequent responses are disabled.
        
Xn      Extended Result Codes

This command selects which subset of the result messages will be 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).  Table
VI indicates the messages which are enabled for each "X" value.  If the modem
is in facsimile mode (+FCLASS=1 or 2), the only message sent to indicate a
connection is CONNECT without a speed indication.

    X0  Disables monitoring of busy tones unless forced 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.
    X1  Disables monitoring of busy tones unless forced by country
        requirements;  send only OK, CONNECT, RING, NO CARRIER, ERROR, NO
        ANSWER, and CONNECT XXXX (XXXX = rate).  Blind dialing is 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.
    X2  Disables monitoring of busy tones unless forced 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.
    X3  Enables monitoring of busy tones;  send only OK, CONNECT, RING, NO
        CARRIER, ERROR, NO ANSWER, CONNECT XXXX and BUSY.  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.
    X4  Enables monitoring of busy tones;  send all messages.  The value 111b
        is written to S22 bits 6, 5, and 4, respectively.  Default


TOP OF PAGE
                     TABLE  VI.  AT Command Result Codes
                     -----------------------------------

NOTE: In the chart below, the "*" indicates which Xn command is supported. 
A numeral indicates which result code will display in place of that message.
For example, the "BUSY" message (result code 7) will be returned when an
ATX3DT or an ATX4DT is issued, but a "NO CARRIER" (result
code 3) will be returned when ATX1DT or ATX2DT is issued.
Furthermore, no result at all is returned when an ATX0DT is issued.

     Short  Long                     n Value in ATXn Command
                                          0  1  2  3  4
     -----  ----------------------   -----------------------
     0         OK                         *  *  *  *  *
     1         CONNECT                    *  *  *  *  *
     2         RING                       *  *  *  *  *
     3         NO CARRIER                 *  *  *  *  *
     4         ERROR                      *  *  *  *  *
     5         CONNECT 1200               1  *  *  *  *
     6         NO DIALTONE                            *
     7         BUSY                          3  3  *  *
     8         NO ANSWER                  *  *  *  *  *
     9         CONNECT 0600               1  *  *  *  *
     10        CONNECT 2400               1  *  *  *  *
     11        CONNECT 4800               1  *  *  *  *
     12        CONNECT 9600               1  *  *  *  *
     13        CONNECT 7200               1  *  *  *  *
     14        CONNECT 12000              1  *  *  *  *
     15        CONNECT 14400              1  *  *  *  *
     16        CONNECT 19200              1  *  *  *  *
     17        CONNECT 38400              1  *  *  *  *
     18        CONNECT 57600              1  *  *  *  *
     22        CONNECT 1200TX/75RX        1  *  *  *  *
     23        CONNECT 75TX/1200RX        1  *  *  *  *
     24        DELAYED                    4  4  4  4  *
     32        BLACKLISTED                            *
     35        DATA                       *  *  *  *  *
     40        CARRIER 300                            *
     44        CARRIER 1200/75                        *
     45        CARRIER 75/1200                        *
     46        CARRIER 1200                           *
     47        CARRIER 2400                           *
     48        CARRIER 4800                           *
     49        CARRIER 7200                           *
     50        CARRIER 9600                           *
     51        CARRIER 12000                          *
     52        CARRIER 14400                          *
     66        COMPRESSION: CLASS 5                   *
     67        COMPRESSION: V.42bis                   *
     69        COMPRESSION: NONE                      *
     76        PROTOCOL: NONE                         *
     77        PROTOCOL: LAPM                         *
     80        PROTOCOL: ALT                          *
     81        PROTOCOL: ALT-CELLULAR                 *
     33        FAX                        *  *  *  *  *

Yn      Long Space Disconnect

This command enables/disables the generation and response to long space (a
break signal greater than 1.6 seconds)disconnect.  The parameter value, if
valid, is written to S21 bit 7.    

    Y0  Disables long space disconnect.  Default
    Y1  Enables long space disconnect.  In non-error correction mode, the
        modem will send a long space of four seconds prior to going on-hook.
        In error correction mode, the modem will respond to the receipt of a
        long space  by going  on-hook.

Zn      Soft Reset and Restore Profile

The modem performs a soft reset and restores (recalls) the configuration
profile according to the parameter supplied.  If no parameter is specified,
zero is assumed.    

    Z0  Soft reset and restore stored profile 0.
    Z1  Soft reset and restore stored profile 1.2.0     
    

=============================================================================
    
2.0      AT& COMMANDS:

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TOP OF PAGE

&Cn     RLSD (DCD) Option

The modem controls the RLSD output in accordance with the parameter supplied.
The parameter value, if valid, is written to S21 bit 5.

    &C0     RLSD remains ON at all times.  Default.
    &C1     RLSD follows the state of the carrier.

&Dn     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.

    &D0     DTR drop is interpreted according to the current &Q setting as
            follows.  Default.
        &Q0,5,6         DTR is ignored (assumed ON).  Allows operation with
                        DTE's which don't provide DTR.
        &Q1,4           DTR drop causes the modem to hang up.  Auto-answer is
                        not affected.
        &Q2,3           DTR drop causes the modem to hang up.  Auto-answer is
                        inhibited.
    &D1     DTR drop is interpreted according to the current &Q setting as
            follows:
        &Q0,1,4,5,6     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.
        &Q2,3           DTR drop causes the modem to hang up.  Auto-answer is
                        inhibited.
    &D2     DTR drop is interpreted according to the current &Q setting as
            follows:
        &Q0..6          DTR drop causes the modem to hang up.  Auto-answer is
                        inhibited.
    &D3     DTR drop is interpreted according to the current &Q setting as
            follows:
        &Q0,1,4,5,6     DTR drop causes the modem to perform a soft reset as
                        if the "Z" command were received. The &Y setting
                        determines which profile is loaded.
        &Q2,3           DTR drop causes the modem to hang up.  Auto-answer is
                        inhibited.

&Fn     Restore Factory Configuration (Profile)

The modem loads a factory default configuration profile. Two different
factory profiles are available. After issuing an AT&F1 or AT&F0, you can view
the profile's defaults by issuing an AT&V. A configuration profile consists
of a subset of S Registers.    

    &F0     Restore factory configuration 0
    &F1     Restore factory configuration 1
    
&Gn     Select Guard Tone

The modem generates the guard tone selected by this command according to the
parameter supplied (DPSK modulation modes only).  This command may not be
permitted in some countries.  The parameter value, if valid, is written to
S23 bits 6 and 7.    
    
    &G0     Disables Guard Tone.  Default.
    &G1     Disables Guard Tone.    &G2     Selects 1800 Hz guard tone.

&Kn     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.

    &K0     Disables flow control.
    &K3     Enables RTS/CTS flow control. (default for data modem modes)
    &K4     Enables XON/XOFF flow control.
    &K5     Enables transparent XON/XOFF flow control.
    &K6     Enables both RTS/CTS and XON/XOFF flow control.

&Mn     Asynchronous/Synchronous Mode Selection

This command determines the DTR operating mode.  The modem treats the &M
command as a subset of the &Q command.

    &M0     Selects direct asynchronous operation.  Note that the command
            sequence &M\N0 selects normal buffered mode, but the command
            sequence \N0&M0 selects the direct mode.  This is because the \N0
            command is analogous to the &Q6 command.  The value 000b is
            written to S27 bits 3, 1, and 0 respectively. (See &Q)
    &M1     (This command is not supported and will return "OK" but will
            cause unknown results.)Selects synchronous connect mode with
            async off-line command mode. The value 001b is written to S27
            bits 3, 1, and 0, respectively.
    &M2     (This command is not supported and will return "OK" but will
            cause unknown results.) Selects synchronous connect mode with
            async off-line command mode. Same as &M1 except &M2 enables DTR
            dialing of directory slot 0. The modem will disconnect if DTR is
            OFF for more than the period in S25 ( in units of hundredths of a
            second):  The data connection will be synchronous.  The value
            010b is written to S27 bits 3, 1, and 0, respectively.
    &M3     (This command is not supported and will return "OK" but will
            cause unknown results.) Selects synchronous connect mode.  This
            mode allows DTR to act as a talk/data switch.  The call is
            manually initiated while DTR is inactive.  When DTR becomes
            active, the handshake proceeds in originate or answer mode
            according to S14 bit 7.  The value 011b is written to S27 bits 3,
            1, and 0, respectively.
            
&Qn     Sync/Async Mode

This command is an extension of the &M command and is used to control the
connection modes permitted.  It is used in conjunction with S36 and S48.
NOTE:   When the &Q0 to &Q4 command is issued to select the mode, the
subsequent connect message will report the DCE speed regardless of the W
command and S95 settings.

    &Q0     Selects direct asynchronous operation.  The value 000b is written
            to S27 bits 3, 1, and 0 respectively. (See &M0)

    &Q1     Selects synchronous connect mode with async off-line command
            mode.  The value 001b is written to S27 bits 3, 1, and 0,
            respectively. (See &M1) (This command is not supported and will
            return "OK" but will cause unknown results.)
    
    &Q2     Selects synchronous connect mode with async off-line command
            mode.  The value 010b is written to S27 bits 3, 1, and 0,
            respectively. (See &M2) (This command is not supported and will
            return "OK" but will cause unknown results.)
    
    &Q3     Selects synchronous connect mode.  This mode allows DTR to act as
            a talk/data switch.  The call is manually initiated while DTR is
            inactive.  When DTR becomes active, the handshake proceeds in
            originate or answer mode according to S14 bit 7.  The value 011b
            is written to S27 bits 3, 1, and 0, respectively. (This command
            is not supported and will return "OK" but will cause unknown
            results.)
    
    &Q4     Select AutoSync operation.  AutoSync operation, when used in
            conjunction with the Hayes Synchronous Interface (HSI) capability
            in the DTE, provides synchronous communication capability from an
            asynchronous terminal.  Writes 100b to S27 bits 3, 1, and 0,
            respectively.
            Starting AutoSync.  Set registers S19, S20, and S25 to the
                                desired values before selecting AutoSync
                                operation with &Q4.  After the CONNECT
                                message is issued, the modem waits the period
                                of time specified by S25 before examining
                                DTR.  If DTR is on, the modem enters the
                                synchronous operating state;  if DTR is off,
                                the modem terminates the line connection and
                                returns to the asynchronous command state.
            Stopping AutoSync.  AutoSync operation is stopped upon loss of
                                carrier or the ON-to-OFF transition of DTR.
                                Loss of carrier will cause the modem to
                                return to the asynchronous command state.  An
                                ON-to-OFF transition of DTR will cause the
                                modem to return to the asynchronous command
                                state and either not terminate the line
                                connection (&D1 active) or terminate the line
                                connection (any other &Dn command active).
    
    &Q5     The modem will try to negotiate an error-corrected link.  The
            modem can be configured using S36 to determine whether a failure
            will result in the modem returning on-hook or will result in
            fallback to an asynchronous connection.  The value 101b is
            written to S27 bits 3, 1,and 0, respectively.  Default
    
    &Q6     Selects asynchronous operation in normal mode (speed buffering).
            The value 110b is written to S27 bits 3, 1, and 0, respectively.

&Rn     RTS/CTS Option

This selects how the modem controls CTS.  CTS operation is modified if
hardware flow control is selected   The parameter value, if valid, is written
to S21 bit 2.  (see &K command)

    &R0     In sync mode, CTS tracks the state of RTS; the RTS-to-CTS delay
            is defined by S26.  In Async mode, CTS acts according to V.25bis
            handshake.
    &R1     In sync mode, CTS is always ON (RTS transitions are ignored).  In
            Async, CTS will drop only if required by flow control.  Default.

&Sn     DSR Override

This command selects how the modem will control DSR.  The parameter value, if
valid, is written to S21 bit 6.

    &S0     DSR will remain ON at all times.  Default
    &S1     DSR will become active after answer tone has been detected and
            inactive after the carrier has been lost.

&Tn     Test and Diagnostics

The modem will perform selected test and diagnostic functions according to
the parameter supplied.  A test can be run only when in an asynchronous
operation in non-error-correction mode (normal or direct mode).  To terminate
a test in progress, the escape sequence (+++) must be entered first, except
for parameters 7, and 8.  If S18 is non-zero, a test will terminate
automatically after the time specified by S18 and display the OK message.
NOTE:  The DTE must be less than or equal to the DCE.

    &T0     Terminates test in progress.  Clears S16.
    
    &T1     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.    &T2     Returns ERROR.
    
    &T3     Initiates local digital loopback, V.54 Loop 2.  Sets S16 bit 2.
            If no connection exists, ERROR is returned. Sets S16 bit 4 when
            the test is in progress.
    
    &T4     Enables digital loopback acknowledgement for remote request,
            i.e., an RDL request from a remote modem is allowed.  Sets S23
            bit 0. Default
    
    &T5     Disables digital loopback acknowledgement for remote request,
            i.e., an RDL (remote digital loopback) request from a remote
            modem is denied.  Clears S23 bit 0.
    
    &T8     Initiates local analog loopback, V.54 Loop 3, with self test. (In
            self test, a test pattern is looped back and checked by the
            modem.)  If a connection exists, the modem hangs up before the
            test is initiated.  When the test is terminated either via
            expiration of S18, or via the &T0 or "H" command, the number of
            detected errors is reported to the DTE.  Sets S16 bit 6 when the
            test is in progress.  This command may not be available in some
            countries due to PTT restrictions.

&V      Display Current Configuration and Stored Profiles

Reports the current (active) configuration, the stored (user) profiles, and
the four stored telephone numbers.  The stored profiles and telephone numbers
are not displayed if the NVRAM is not installed or is not operational as
detected by the NVRAM test during reset processing.

&Wn     Store Current Configuration

Saves the current (active) configuration (profile), including S Registers, in
one of the two user profiles in NVRAM as denoted by the parameter value.
This command will yield an ERROR message if the NVRAM is not installed or is
not operational as detected by the NVRAM test. The current configuration is
comprised of a list of storable parameters illustrated in the &V command.
These settings are restored to the active configuration upon receiving an Zn
command or at power up. (see &Yn command)

    &W0     Store the current configuration as profile 0.
    &W1     Store the current configuration as profile 1.

&Yn     Designate a Default Reset Profile

Selects which user profile will be used after a hard reset.  When &Yn is
changed (e.g. &Y1 command) the parameter is automatically written to NVRAM.

    &Y0     The modem will use profile 0.
    &Y1     The modem will use profile 1.
    
&Zn=x   Store Telephone Number

The modem can store up to 4 telephone numbers.  Each dial string can contain
a maximum of 42 digits.

    &Zn=x   (n = 0 to 3, and x = dial string) (requires 256-byte NVRAM)


=============================================================================

3.0      AT% COMMANDS:

=============================================================================

TOP OF PAGE

%En     Enable/Disable Line Quality Monitor and Auto-Retrain
        Fallback/Fall Forward:

Controls whether or not the modem will automatically monitor the line quality
and request a retrain (%E1 and %E3) or fall back when line quality is
insufficient or fall forward when line quality is sufficient (%E2).  Applies
to dialup line only.  The parameter value, if valid, is written to S41 bits
2 and 6. If enabled, the modem attempts to retrain for a maximum of 30seconds.

    %E0     Disable line quality monitor and auto-retrain.  Default.
    %E1     Enable line quality monitor and auto-retrain.
    %E2     Enable line quality monitor and fallback/fall forward.
    %E3     Enable line quality monitor and auto-retrain, but hang-up
            immediately when EQM reaches hang-up threshold.  AKA Fast Hangup.

When %E2 is active, the modem monitors the line quality (EQM).  When line
quality is insufficient, the modem will initiate a rate renegotiation to a
lower speed within the V.32bis/V.32 modulation speeds.  The modem will keep
falling back if necessary until the speed reaches 4800 bps.  Below this rate,
the modem will do retrains only if EQM thresholds are exceeded.  If the EQM
is sufficient for at least one minute, the modem will initiate a rate
renegotiation to a higher speed within the V.32/V.32bis modulation speeds.
The rate renegotiation will be done without a retrain if a V.32bis connection
is established.

Speeds attempted during fallback/fall forward are those shown to be available
in the rate sequences exchanged during the initial connection. Fallback/fall
forward is available in error correction and normal modes, but not in direct
mode or synchronous mode with external clocks.


%L-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.
   
%Q - 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 or fallback/fall 
   forward may be initiated if enabled by %E1, %E2 or %E3.   Example:   AT%Q
         015

%TTn - PTT Testing Utilities:

   Facilitates PTT testing of signal levels by providing continuous signals    
   regardless of whether the modem is connected or not.  The signal 
   transmitted is in accordance with the parameter provided.
   This is a range of commands that allow the user to initiate a series of 
   signals that are necessary for PTT approval.  The signals emitted include 
   answer tone, modulation, carriers, and other pertinent signals.  A test is 
   initiated on the receipt of an %TT ("T" is a password), and the test is 
   aborted when any keyboard character is entered.  The modem will 
   continuously transmit the tone or carrier according to the parameter 
   supplied.      
   
      %TT00-%TT09 DTMF tone dial digits 0 to 9.
      %TT0A      DTMF digit *.      %TT0B      DTMF digit A.
      %TT0C      DTMF digit B.      %TT0D      DTMF digit C.
      %TT0E      DTMF digit #.      %TT0F      DTMF digit D.
      %TT10      V.21 channel no. 1 mark (originate) symbol.
      %TT11      V.21 channel no. 2 mark symbol.
      %TT12      V.23 backward channel mark symbol.
      %TT13      V.23 forward channel mark symbol.
      %TT14      (NotSupported) V.22 originate (call mark) signall at 600 bps.
      %TT15      V.22 originate (call mark) signalling at 1200 bps.
      %TT16      V.22bis originate (call mark) signalling at 2400 bps.
      %TT17      V.22 answer signalling (guard tone if PTT required).
      %TT18      V.22bis answer signalling (guard tone if required).
      %TT19      V.21 channel no. 1 space symbol.      %TT20    V.32 9600 bps.
      %TT21      V.32bis 14400 bps.
      %TT1A      V.21 channel no. 2 space symbol.
      %TT1B      V.23 backward channel space symbol.
      %TT1C      V.23 forward channel space symbol.
      %TT30      Silence (on-line), i.e., go off-hook.
      %TT31      V.25 answer tone.      %TT32      1800 Hz guard tone.
      %TT33      V.25 calling tone (1300 Hz).
      %TT34      Fax calling tone (1100 Hz).      %TT40      V.21 channel 2.
      %TT41      V.27ter 2400 bps.      %TT42      V.27ter 4800 bps.
      %TT43      V.29 7200 bps.      %TT44      V.29 9600 bps.
      %TT45      V.17 7200 bps long train.
      %TT46      V.17 7200 bps short train.
      %TT47      V.17 9600 bps long train.
      %TT48      V.17 9600 bps short train.
      %TT49      V.17 12000 bps long train.
      %TT4A      V.17 12000 bps short train.
      %TT4B      V.17 14400 bps long train.
      %TT4C   V.17 14400 bps short train.

   To permit output signal spectra measurement, it is possible to transmit 
   data in the absence of a received signal by setting S10 equal to 255.


============================================================================

4.0      AT\ COMMANDS:

============================================================================

TOP OF PAGE

\An - Select Maximum MNP Block Size:

   The modem will operate an MNP error corrected link using a maximum block 
   size controlled by the parameter supplied.  The parameter value, if 
   valid, is written to S40 bits 6 and 7.      \A0  64 characters

      \A1  128 characters  Default      
      \A2  192 characters
      \A3  256 characters
      
      
\Bn - 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 break through the active error correction protocol, 
   giving no indication of the length.

      \B1-\B9   Break length in 100 mS units. (default = 3) (Non-error 
                corrected mode only) 

   NOTE:   When the modem receives a break from the remote modem, break is 
           passed to the DTE as follows:  In non-error correction mode, the 
           length is passed.  
           

\Ln - MNP Block/Stream Mode Select:

   At connection time, this command controls the selection between block and 
   stream modes of operation in MNP.  The parameter value, if valid, is 
   written to S41 bit 4.      
      
      \L0   Use stream mode for MNP connection.  Default
      \L1   Use interactive block mode for MNP connection.  This command will 
            accept block mode but implement stream mode.


\Gn - Modem-to-Modem Flow Control (XON/XOFF):

   In non-error correction mode, the modem enables or disables the generation 
   or recognition of modem-to-modem XON/XOFF flow control according to the 
   parameter supplied.  The parameter value, if valid, is written to S41 
   bit 3.   In error correction mode, the setting of modem-to-modem XON/XOFF 
   flow control is ignored.  However, the serial port flow control settings 
   (AT&K) remain active during a reliable link.   Due to the buffering system 
   used in the modem, modem-to-modem flow control is normally disabled.

      \G0   Disables modem-to-modem XON/XOFF flow control.  Default
      \G1   Enables modem-to-modem XON/XOFF flow control.


\Kn - Break Control:

   Controls the response of the modem to a break received from the DTE or the 
   remote modem or the \B command according to the parameter supplied.  The 
   parameter value, if valid, is written to S40 bits 3, 4, and 5.  The 
   response is different for 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:

      \K0   Enter on-line command mode, no break sent to the remote modem.
      \K1   Clear data buffers and send break to remote modem.
      \K2   Same as 0.      \K3   Send break to remote modem immediately.
      \K4   Same as 0.
      \K5   Send break to remote modem in sequence with transmitted data. 
             Default.

   The second state 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:
      \K0   Clear data buffers and send break to remote modem.
      \K1   Clear data buffers and send break to remote modem. (Same as 0)
      \K2   Send break to remote modem immediately.
      \K3   Send break to remote modem immediately. (Same as 2)
      \K4   Send break to remote modem in sequence with data.
      \K5   Send break to remote modem in sequence with data. (Same as 4) 
            Default

   The third state is where a break is received from a remote modem during a 
   non-error corrected connection:
      \K0   Clears data buffers and sends break to the DTE.
      \K1   Clears data buffers and sends break to the DTE. (Same as 0)
      \K2   Send a break immediately to DTE.
      \K3   Send a break immediately to DTE. (Same as 2)
      \K4   Send a break in sequence with received data to DTE.
      \K5   Send a break in sequence with received data to DTE. (Same as 4) 
             Default

   Note:   When S82 is modified, the modem converts the Hayes specific value 
           to the \K format and updates S40 to match.


============================================================================

5.0      Error Detection And Data Compression Commands

============================================================================

TOP OF PAGE

\Nn - Operating Mode:

   This command controls the preferred error correcting mode to be negotiated 
   in a subsequent data connection.  This command is affected by the firmware  
   configuration.

      \N0   Selects normal speed buffered mode (disables error-correction 
            mode) (Forces &Q6)
      
      \N1   Serial interface selected - selects direct mode and is equivalent 
            to &M0, &Q0 mode of operation. (forces &Q0)  Parallel interface 
            selected - Same as \N0.
      
      \N2   Selects reliable (error-correction) mode.  The modem will first 
            attempt an 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) 
      
      \N3   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)  Default
      
      \N4   Selects LAPM error-correction mode.  Failure to make a LAPM error-
            correction connection results in the modem hanging up. (Forces &Q5 
            and S48=0) NOTE:  The   -K1 command can override the \N4 command.
      
      \N5   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)


\S - Report Active Configuration (Not supported on all modems)
     The modem reports the current (active) configuration for display.


AT% Commands:


%C - Enable/Disable Data Compression:

   Enables or disables data compression negotiation.  The modem can perform
   data compression only on an error corrected link.  The parameter value,
   if valid, is written to S41 bits 0 and 1.

      %C0   Disables data compression.  Resets S46 bit 1.
      %C1   Enables MNP 5 data compression negotiation.  Resets S46 bit 1.
      %C2   Enables V.42bis data compression.  Sets S46 bit 1.
      %C3   Enables both V.42bis and MNP 5 data compression.  Sets S46 bit 1. 
             Default


============================================================================

6.0      MNP 10 COMMANDS: 
         (Applies only to XJ2144, CC4144, and EM1144T models.)

============================================================================

TOP OF PAGE

AT) Commands:


)Mn - Enable Cellular Power Level Adjustment:

   Enables or disables automatic adjustment of the transmit power level during 
   link negotiation for reliable links to accommodate the signaling 
   requirements of cellular telephone equipment.  The parameter value, if 
   valid, is written to S40 bit 2.  Note that the @Mn command sets the 
   initial transmit level.

      )M0   Disables power level adjustment during MNP 10 link negotiation. 
             Default
      )M1   Enables power level adjustment during MNP 10 link negotiation.


AT* and AT- Commands:


*Hn - Link Negotiation Speed:

   This command controls the connection speed for link negotiations before 
   upshift occurs between two MNP Class 10 modems.  The parameter value, if 
   valid, is written to S28 bits 6 and 7.

      *H0   Link negotiation occurs at the highest supported speed.  Default
      *H1   Link negotiation occurs at 1200 bps.
      *H2   Link negotiation occurs at 4800 bps.


-Kn - MNP Extended Services:

   Enables or disables conversion of a V.42 LAPM connection to an MNP 10 
   connection.    The parameter value, if valid, is written to S40 bit 0.

      -K0   Disables V.42 LAPM to MNP 10 conversion.   Default
      -K1   Enables V.42 LAPM to MNP 10 conversion.
      -K2   Enables V.42 LAPM to MNP 10 conversion; inhibits MNP Extended 
            Services initiation during V.42 LAPM answer mode detection 
            phase.
            

-Qn - Enable Fallback to V.22 bis/V.22:

   Enables or disables fallback from MNP 10 to V.22 bis/V.22.  The parameter 
   value, if valid, is written to S41 bit 7.

      -Q0   Disables fallback to 2400 bps (V.22bis) and 1200 bps (V.22).  
            Fallback is enabled only to 4800 bps.
      -Q1   Enables fallback to 2400 bps (V.22bis) and 1200 bps (V.22). 
             Default


@Mn - Initial Cellular Power Level Setting:

   Sets the initial transmit power level for upshift at connect until line 
   conditions can be determined.  @M0 corresponds to -26 dBm, @M1 corresponds 
   to -30 dBm, @M2 through @M10 correspond to -10 dBm, and @M11 through @M31 
   correspond to -11 dBm to -31 dBm , respectively.  The parameter value, if 
   valid, is written to S201 bit 0-4.      
      @M0       -26 dBm      @M1       -30 dBm      @M2      -10 dBm
      @M3 - @M10   -10 dBm
      @M11      -11 dBm      @M12      -12 dBm      @M13     -13 dBm
      @M14      -14 dBm      @M15      -15 dBm      @M16     -16 dBm
      @M17      -17 dBm      @M18      -18 dBm      @M19     -19 dBm
      @M20      -20 dBm      @M21      -21 dBm      @M22     -22 dBm
      @M23      -23 dBm      @M24      -24 dBm      @M25     -25 dBm      
      @M26      -26 dBm *    Default                @M27     -27 dBm      
      @M28      -28 dBm
      @M29      -29 dBm      @M30      -30 dBm      @M31     -31 dBm      


:E - Compromise Equalizer Enable:

   Enables or disables the V.32 compromise equalizer.  The parameter value, if
   valid, is written to S201 bit 5.  This command can be used when the modem 
   is attached to either a flat line or a cellular connection.

      :E0   Disables the equalizer.      
      :E1   Enables the equalizer.  Default

=============================================================================

7.0   S REGISTER SUMMARY:How S Registers work (See also: S Register Definitions)

=============================================================================

TOP OF PAGE

     Your Megahertz modem has storage spaces called registers which can hold 
     a user-specified range of values. To set all registers to their default
     values issue an AT&F  in the terminal mode of a communications 
     package. To set the value of a specific register, issue an 
     ATSn=xxx , where n is the register number, and xxx is the 
     decimal (base 10) value. 
     
     For example, to change register 8 to wait for 3 seconds when a comma 
     is encountered in the dialing string, you would type in ATS8=3 
     in terminal mode.     
     The "Save?" column indicates if the register's contents are saved
     in a user profile when an AT&W or AT&W1 is issued to the modem.         

Registers not specifically listed are reserved or unsupported.

Register           Function                   Range        Units      Default
-------- -----------------------------------  ------   ------------   -------
S0       Rings to Auto-Answer                 0-255        Rings      0

S1       Ring Counter                         0-255        Rings      0

S2       Escape Character                     0-255        ASCII      43

S3       Carriage Return Character            0-127        ASCII      13

S4       Line Feed Character                  0-127        ASCII      10

S5       Backspace Character                  0-255        ASCII      8

S6       Wait Time for Dial Tone              2-255        seconds    4

S7       Wait for Carrier                     1-255        seconds    50

S8       Pause Time for (,) Comma             0-255        seconds    2

S9       Carrier Detect Response Time         1-255        1/10 sec   6

S10      Carrier Loss Disconnect Time         1-255        1/10 sec   14

S11      Touch Tone (DTMF) Duration           50-255       1/1000 sec 95

S12      Escape Code Guard Time               0-255        2/100sec   50

S14      General Bit Mapped Options                                   138 (8ah)

S16      Test Mode Bit Mapped Options (&T)                            0

S18      Test Timer                           0-255        seconds

S21      V.24/General Bit Mapped Options--                            4 (04h)

S22      Speaker/Results Bit Mapped Options--                         117 (75h)

S23      General Bit Mapped Options--                                 55 (37h)

S24      Sleep Inactivity Timer               0-255        seconds    0

S25      Delay to DTR off                     0-255        1/100 sec  5

S26      RTS-to-CTS Delay                     0-255        1/100 sec  1

S27      General Bit Mapped Options--                                 73 (49h)

S28      General Bit Mapped Options--                                 0

S29      Flash Dial Modifier Time             0-255        10 ms      0

S30      Disconnect Activity Timer            0-255        10 sec     0

S31      General Bit Mapped Options--                                 2

S32      XON Character                        0-255        ASCII      17 (11h)

S33      XOFF Character                       0-255        ASCII      19 (13h)

S36      LAPM Failure Control--                                       7

S37      Line Connection Speed--                                      0

S38      Delay Before Forced Hangup           0-255        seconds    20

S39      Flow Control--                                               3

S40      General Bit Mapped Options--                                 105 
(69h) No MNP 10. 107 (6Bh) MNP 10

S41      General Bit Mapped Options--                                 3

S46      Data Compression Control--                                   138

S48      V.42 Negotiation Control--                                   7

S80      Soft Switch Functions--                                      0

S82      LAPM Break Control--                                         128 (40h)

S86      Call Failure Reason Code            0-255

S91      PSTN Transmit Attenuation Level     l0-15         dBm        10

S92      Fax Transmit Attenuation Level      l0-15         dBm        10

S95      Result Code Messages Control--                               0

S99      Leased Line Transmit Level          0-15          dBm        10

S201     Cellular Transmit Leve              l0-63                    58

S202     Remote Access Escape Character      0-255         ASCII      170

=============================================================================

8.0      XJ3144 and CC6144 Commands

=============================================================================
TOP OF PAGE
The commands listed below apply only to the XJ3144 and CC6144.

Dn      Dial

In addition to the dial modifiers listed under the Dn command hading in
Section 1.0, the following modifiers are available on the XJ3144 and CC6144.

        J       Perform MNP10 link negotiation at highest speed for this call
                only.
        K       Enable power level adjustment during MNP10 link for this call
                only.
        R       Wait 10 seconds after dialing and go into answer mode.  Must
                appear at end of dial string.
        &       Wait for credit card bong.

In      Product Identification

In addition to the product identification commands listed in Section 1.0, I7
can be used to report which cellular cable is attached, if any.

&Fn     Restore Factory Profile

When an &F is issued, -SEC is set to 0, disabling MNP10EC.  &F1 sets -SEC to
1, enabling MNP10EC.  See -SEC below.

-SDR=n  Distinctive Ring Reporting
----------------------------------
        -SDR=1      Type 1 Distinctive Ring Detect
        -SDR=2      Type 2 Distinctive Ring Detect
        -SDR=3      Type 1 and Type 2 Distinctive Ring Detect
        -SDR=4      Type 3 Distinctive Ring Detect
        -SDR=5      Type 1 and Type 3 Distinctive Ring Detect
        -SDR=6      Type 2 and Type 3 Distinctive Ring Detect
        -SDR=7      Types 1, 2, and 3 Distinctive Ring Detect

    Distinctive Ring Types
    Type        On     Off    On     Off     On     Off    Sound
    -------------------------------------------------------------------------
      1         2.0    4.0                                 Rinnnnnnnnnng
      2         0.8    0.4    0.8    4.0                   Ring Ring
      3         0.4    0.2    0.4    0.2    0.8     4.0    Ring Ring Rinnng

-SEC=n  LAPM and MNP Link Control
---------------------------------
        -SEC=0          Disable LAPM or MNP10.  EC transmit level set in
                        register S91.
        -SEC=1,0..30    Enable LAPM or MNP10.  EC transmit level set to value
                        after comma (0 to 30).

~Dn     Factory Configured Operating Profile
--------------------------------------------
        ~D0     Disable (No Error Correction, No Data Compression)
        ~D1     MNP4        ~D2     MNP5        ~D3     V.42
        ~D4     V.42bis

$H      Help Screen

Sending the $H command causes the modem to return the following help screen:
Type in the letters AT followed by one of the following commands (CMD),
to activate the following modem features.

CMD   MODEM FEATURE                     CMD   MODEM FEATURE
---   -------------                     ---   -------------
$H    Displays this help screen         F0    Enable auto-mode detection
&F0   Reset to Factory Defaults         F5    Force 2400 connection
%C0   Disable Data Compression          F8    Force 9600 connection
%C3   Enable Data Compression           F10   Force 14400 connection
&K0   Disable Flow Control              M0    Set Speaker - always off
&K3   Enable RTS/CTS Flow Control       M1    Set Speaker - on until connect
&K4   Enable XON/XOFF Flow Control      L0    Set Speaker volume low
X3    Disable Dialtone detection        L2    Set Speaker volume medium
X4    Enable Dialtone detection         L3    Set Speaker volume high
~D0   Disable error and data compression
~D1   Enable MNP4 (error correction without data compression)
~D2   Enable MNP5 (MNP4 with 2:1 data compression)
~D3   Enable V.42 (error correction)
~D4   Enable V.42bis (V.42 with 4:1 data compression)


=============================================================================

9.0      S Register Definitions (See also: S REGISTER SUMMARY)

=============================================================================
TOP OF PAGE
S0 - Number of Rings to Auto-Answer:

   Sets the number of the rings required before the modem automatically 
   answers a call.  Setting this register to zero disables auto-answer mode.
      Range: 0-255 rings      Default:  0 (US models)      2 (W-Class models)


S1 - Ring Counter:

   S1 is incremented each time the modem detects 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:

   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:

   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:

   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 for Dial Tone Before Blind Dialing, or After "W" Dial 
              Modifier (W-Class models):

   1.   Sets the length of time, in seconds, the 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.

   2.   For W-Class models, S6 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.  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:  4


S7 - Wait Time For Carrier After Dial, For Silence, or For Dial Tone 
              After "W" Dial Modifier (US Models):

   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.   For US Models, S7 sets the length of time, in seconds, that modem will 
        wait for dial tone when encountering the "W" dial modifier before 
        continuing with the next dial string parameter.
      Range: 1-255 seconds      Default: 50


S8 - Pause Time For Dial Delay:
   
   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:
   
   Sets the time, in tenths of a second, that the carrier must be present 
   before the modem considers it valid and turns on RLSD.  As this time is 
   increased, there is less chance to detect a false carrier due to noise from 
   the telephone line.      Range: 1-255 tenths of a second
      Default: 6 (0.6 second)


S10 - Lost Carrier To Hang Up Delay:
   
   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:
   
   Sets the duration of tones in DTMF dialing (US models only).  This value 
   has no effect on pulse dialing.  For W-Class models, this parameter 
   is a country parameter loaded by ConfigurACE.     Range: 50-255 milliseconds
      Default: 95 (95 milliseconds)


S12 - Escape Code Guard Time:
   
   Defines the maximum period, in fiftieths of a second, allowed between 
   consecutive asynchronous escape characters (+) for the escape sequence to 
   be considered valid.      Range: 0-255 1/50 of a second
      Default: 50 (1 second) 


S13 - Reserved:


S14 - General Bit Mapped Options:
   
   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  Default8.14.16   S15 - Reserved:


S16 - General Bit Mapped Test Options:
   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  Default            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 =  Enabled (&T8)
         Bit 7 -   Not used


S17 - Reserved:


S18 - Test Timer:
   
   Sets the length of time, in seconds, that the modem conducts a test 
   (commanded by &Tn) before returning to the command mode.  If this register 
   value is zero, the test will not automatically terminate; the test must be 
   terminated from the command mode by issuing an &T0 or "H" command.  When 
   S18 is non-zero, the modem returns the OK message upon test termination.
      Range: 0-255 seconds      Default: 0


S19 - AutoSync Register:
   
   Defines the options for AutoSync operation (see Q4 command).  S19 must be 
   set to the desired value before &Q4 is issued.      Default: 0

         Bit 0 -   Reserved         Bit 1 -   BSC/HDLC format select
            0 =  BSC selected  Default            1 =  HDLC selected
         Bit 2 -   Address detection enable/disable
            0 =  Disabled  Default            1 =  Enabled
         Bit 3 -   NRZI/NZI coding select            0 =  NRZI  Default
            1 =  NZI         Bit 4 -   Idle indicator select
            0 =  Mark idle  Default            1 =  Flag or sync idle
         Bit 5-7   Reserved


S20 - AutoSync HDLC Address or BSC Sync Character:
   
   Defines the HDLC address (S19 bit 1=1) or BSC Sync character (S19 bit 1=0) 
   for AutoSync operation (See &Q4 command).  S20 must be set to the desired 
   value before &Q4 is issued.      Range: 0-255 seconds      Default: 0


S21 - V.24/General Bit Mapped Options:
   
   Indicates the status of command options.      Default: 4 (04h) (00000100b)

         Bit 0 -   Set by &Jn command but ignored otherwise.
            0 =  &J0  Default            1 =  &J1         Bit 1 -   Reserved
         Bit 2 -   CTS behavior (&Rn)            0 =  CTS tracks RTS (&R0)
            1 =  CTS always on (&R1)  Default
         Bit 3,4 - DTR behavior (&Dn)            0 =  &D0 selected  Default
            1 =  &D1 selected            2 =  &D2 selected
            3 =  &D3 selected         Bit 5 -   RLSD (DCD) behavior (&Cn)
            0 =  &C0 selected  Default            1 =  &C1 selected
         Bit 6 -   DSR behavior (&Sn)            0 =  &S0 selected  Default
            1 =  &S1 selected         Bit 7 -   Long space disconnect (Yn)
            0 =  Y0  Default            1 =  Y1


S22 - Speaker/Results Bit Mapped Options:
   
   Indicates the status of command options.      Default: 118 (76h) (01110110b)

         Bit 0,1 - Speaker volume (Ln)            0 =  Off (L0)
            1 =  Low (L1)            2 =  Medium (L2)  Default
            3 =  High (L3)         Bit 2,3 - Speaker control (Mn)
            0 =  Disabled (M0)            1 =  Off on carrier (M1)  Default
            2 =  Always on (M2)            3 =  On during handshake (M3)
         Bit 4,5,6 - Limit result codes (Xn)            0 =  X0
            4 =  X1            5 =  X2            6 =  X3
            7 =  X4  Default         Bit 7-   Reserved


S23 - General Bit Mapped Options:
   
   Indicates the status of command options.
      Default:  55 (37h) (00110111b) (US models)
         183 (B7h) (10110111b) (W-Class models)         Bit 0-   Grant RDL
            0 =  RDL not allowed (&T5)
            1 =  RDL allowed (&T4)  Default       Bit 1,2,3 - Assumed DTE Rate
            0 =  0 - 300 bps            1 =  600 bps            2 =  1200 bps
            3 =  2400 bps  Default            4 =  4800 bps
            5 =  9600 bps            6 =  19200 bps
         Bit 4,5 - Assumed DTE parity            0 =  even
            1 =  not used            2 =  odd            3 =  none  Default
         Bit 6,7 - Guard tone (&Gn)
            0 =  None (&G0) (default for US models)            1 =  None (&G1)
            2 =  1800 Hz (&G2) (default for W-Class models)


S24 - Sleep Inactivity Timer:
   
   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 the S24 value is zero, neither DTE line nor telephone 
   inactivity will cause the modem to enter the sleep mode.
      Range: 0-255 seconds      Default: 1


S25 - Delay To DTR:
   
   Sets the length of time that the modem will ignore DTR before hanging 
   up.  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:
   
   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


S27 - General Bit Mapped Option:
   
   Indicates the status of command options.
      Default:  73 (49h) (01001001b) (US models with ECC)
         74 (4Ah) (01001010b) (US models without ECC)
          9 (09h) (00001001b) (W-Class models)
   
         Bit  3,1,0   Selection (&Mn/&Qn)            3,1,0
            0,0,0 =     &M0 or &Q0            0,0,1 =     &M1 or &Q1
            0,1,0 =     &M2 or &Q2            0,1,1 =     &M3 or &Q3
            1,0,0 =     &Q4            1,0,1 =     &Q5 (default for ECC models)
            1,1,0 =     &Q6 (default for non-ECC models)
         Bit 2 -   Leased line control (&Ln)
            0 =  Dial up line (&L0)  Default            1 =  Leased line (&L1)
         Bit 4,5 - Internal clock select (&Xn)
            0 =  Internal clock (&X0)  Default
            1 =  External clock (&X1)             2 =  Slave clock (&X2) 
         Bit 6 -   CCITT/Bell mode select (Bn)
            0 =  CCITT mode (B0) (default for W-Class models)
            1 =  Bell mode (B1) (default for US models)
         Bit 7 - Reserved 8.14.29   S28 - General Bit Mapped Options:
      Default: 0         Bit 0 -   V.23 split screen (\W)
            0 =  Disabled (\W0)  Default            1 =  Enabled (\W1)
         Bit 1 -   V.23 split screen direction
            0 =  75 Tx/1200 Rx (%F1)  Default            1 =  1200 Tx/75 Rx
         Bit 2 -   Reserved (always 0)         Bit 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 -   Reserved         Bit 6,7 -  MNP link negotiation speed (*Hn)
            0 =  Link negotiation at highest speed (*H0)  Default
            1 =  Link negotiation at 1200 bps (*H1)
            2 =  Link negotiation at 1200 bps (*H1)


S29 - Flash Dial Modifier Time:
   
   Sets the length of time, in units of 10 mS, that the modem will go on-hook 
   when it encounters the flash (!) dial modifier in the dial string.  The 
   time can be limited as it is a country dependent parameter.
      Range: 70 10 mS intervals      Default: 70 (disabled)


S30 - Disconnect Inactivity Timer:
   
   Sets the length of time, in tens of seconds, that the modem will stay 
   on-line 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 - General Bit Mapped Options:      Default: 194 (C2h) (11000010b)
   
         Bit 0 -   Reserved
         Bit 1 -   Controls auto line speed detection (Nn)
            0 =  Disabled (N0)            1 =  Enabled (N1)  Default
         Bit 2,3 - Controls error correction progress messages (Wn)
            0 =  DTE speed only (W0)  Default
            1 =  Full reporting (W1)            2 =  DCE speed only (W2)
         Bit 3 -   Reserved         Bit 4-7 - Reserved 


S32 - XON Character:   Sets the value of the XON character.
      Range: 0-255, ASCII decimal      Default: 17 (11h)


S33 - XOFF Character:   Sets the value of the XOFF character.
      Range: 0-255, ASCII decimal      Default: 19 (13h)


S34-S35 - Reserved:


S36 - LAPM Failure Control (Applies to ECC Models Only):
      Default: 7 (07h) (00000111b)
   
       Bit 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
      Bit 3-7 - Reserved 8.14.37   S37 - Desired Line Connection Speed:
                Default: 0
      
      Bit 0-3 -   Desired line connection speed.  This is interlinked 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 auto mode connection (F0).  Default
         1-3=   Attempt to connect at 300 bps (F1).
         4  =   Reserved.
         5  =   Attempt to connect at 1200 bps (F4).
         6  =   Attempt to connect at 2400 bps (F5).
         7  =   Attempt to connect at V.23 (F3).
         8  =   Attempt to connect at 4800 bps (F6).
         9  =   Attempt to connect at 9600 bps (F8).
         10 =   Attempt to connect at 12000 bps (F9).
         11 =   Attempt to connect at 14400 bps (F10).
         12 =   Attempt to connect at 7200 bps (F7).
      Bit 4-7 - Reserved8.14.38   S38 - Delay Before Forced Hang Up:

   This register 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 register 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:      Default: 3 (03h) (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 8.14.40   
         
S40 - General Bit Mapped Options:

  Indicates the status of command options.     
  Default:  104 (68h) (01101000b)
  
        Bit 0-1  MNP Extended Services (-Kn) [High Speed]
           0 =  Disable extended services (-K0) (default for non-MNP 10 models)
           1 =  Enable extended services (-K1) (default for MNP 10 models)
           2 =  Enable extended services (-K2)
        Bit 0 -  MNP Extended Services (-Kn) [Low Speed]
           0 =  Disable extended services (-K0) (default for non-MNP 10 models)
           1 =  Enable extended services (-K1) (default for MNP 10 models)
        Bit 1 -  Enable fallback to V.22bis/V.22 (-Qn) [Low Speed]
           0 = Disabled (-Q0)            1 = Enabled (-Q1)  Default
        Bit 2 -  Power Level Adjustment for Cellular Use ()Mn)
           0 = Auto-adjustment ()M0)  Default
           1 = Force adjustment ()M1)         Bit 3-5 -  Break handling (\Kn)
           0 =  \K0            1 =  \K1            2 =  \K2            3 =  \K3
           4 =  \K4            5 =  \K5  Default
        Bit 6-7 -  MNP block size (\An)            0 =  64 chars (\A0)
           1 =  128 chars (\A1)  Default            2 =  192 chars (\A2)
           3 =  256 chars (\A3)8.14.41   
           
S41 - General Bit Mapped Options:

   Indicates the status of command options.      
   Default: 131 (83h) (10000011b)
         
         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
         Bit 2,6 -  Auto retrain and Fallback/fall forward (%En)
            Bit 6   Bit 2
            0   0 =  Retrain and Fallback/fall forward disabled (%E0)  Default
            0   1 =  Retrains enabled (%E1)
            1   0 =  Fallback/fall forward enabled (%E2) (not applicable to  
                     RC96V24AC and RC14V24AC)
         Bit 3 -   Modem-to-modem flow control
            0 =  Disabled (\G0)  Default            1 =  Enabled (\G1)
         Bit 4 -   Block mode control (\Ln)
            0 =  Stream mode (\L0)  Default            1 =  Block mode (\L1)
         Bit 5 -   Reserved
         Bit 7 -   Enable fallback to V.22 bis/V.22 (-Qn) [High Speed] 
            0 =  Disabled (-Q0)            1 =  Enabled (-Q1)  Default


S46 - Data Compression Control:
   
   Controls selection of compression.  The following actions are executed for 
   the given values:      Range: 136 or 138      Default: 138
   
         S46=136   Execute error correction protocol with no compression.
         S46=138   Execute error correction protocol with compression.  Default


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      Disable negotiation; bypass the detection and negotiation 
                    phases; and proceed with LAPM.
         S48=7      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.


S80 - Soft-Switch Functions: (Not Supported)
   
   S80 is only applicable if the EPROM has been so customized by ConfigurACE. 
   S80 bits are the "soft" equivalent of four hardware input signals.  The 
   hardware signal is indicated corresponding to each bit.      Default:  1
   
         Bit 0 - Must be set to a 1         Bit 1 - Reserved
         Bit 2 - Reserved         Bit 3 - Leased line originate/answer select
            0 =  Answer select            1 =  Originate select
         Bit 4 - Leased line enable/disable            0 =  Disabled
            1 =  Enabled
         Bit 5 - V.25bis/AT command mode select (AT/V25B signal)
            0 =  AT selected            1 =  V.25bis selected
         Bit 6 - Remote configuration permitted (REMCONF signal)
            0 = Remote configuration not permitted
            1 = Remote configuration permitted
         Bit 7 - Call back security enforcement (SECACC signal)
            0 =   Call back security disabled
            1 =   Call back security enabled


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 specific application.  LAPM specifies 
   three methods of break signal handling:  In sequence, expedited, and 
   destructive.  If an invalid 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 both 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 this S
Register to help determine the reason for the failed connection.  S86 records
the first event that contributes to a NO CARRIER message.  The cause codesare:

    S86=0   Normal disconnect, no error occurred.    S86=4   Loss of carrier.
    S86=5   V.42 negotiation failed to detect an error-correction modem at
            the other end.    S86=6   No response to feature negotiation.
    S86=7   This modem is asynchronous only; the other modem is synchronous
            only.    S86=8   No framing technique in common.
    S86=9   The modems could not find a common protocol.
    S86=10  Bad response to feature negotiation.
    S86=11  No sync information from remote modem.
    S86=12  Normal disconnect initiated by the remote modem.
    S86=13  Remote modem does not respond after 10 re-transmissions of the
            same message.    S86=14  Protocol violation.

S91     PSTN Transmit Attenuation Level:

Sets the transmit attenuation level from 0 to 15 dbm for the PSTN mode,
resulting in a transmit level from 0 to -15 dbm.
Default:  10 (-10 dBm transmit level)

S92     Fax Transmit Attenuation Level:

Sets the transmit attenuation level from 0 to 15 dbm for the fax mode,
resulting in a transmit level from 0 to -15 dbm.
Default:  10 (-10 dBm transmit level)S95     Extended Result Codes:
The bits in this register can be set to override some of the Wn command
options.  A bit set to a 1 in this register will enable the corresponding
result code regardless of the Wn setting.  Also, refer to Table V.Default: 0

    Bit 0 = CONNECT result code indicates DCE speed instead of DTE speed.
    Bit 1 = Append/ARQ to CONNECT XXXX result code in error-correction mode
            (XXXX = rate; see Table VI).
    Bit 2 = Enable CARRIER XXXX result code (XXXX = rate; see Table VI).
    Bit 3 = Enable PROTOCOL XXXX result code (XXXX = protocol identifier; see
            Table VI).
    Bit 5 = Enable COMPRESSION result code (XXXX = compression type; see
            Table VI).
            
S99     Leased Line Transmit Attenuation Level:

Sets the transmit level, in dbm, for the leased line mode.Default: 10

S201    MNP10 Parameters:

The bits in this register can be set to override some of the Wn command
options.  A bit set to a 1 in this register will enable the corresponding
result code regardless of the Wn setting.  Also, refer to Table V.
Default: 58 (3Ah) (00111010b)
    Bit 0-4 =   Initial Cellular Power Level Setting (@Mn)
    Bit 5 =     Compromise Equalizer Enable Command (:En)

S202    Remote Access Escape Character:

S202 holds the decimal value of the ASCII character used as the escape
character in the escape sequence from on-line to Remote Access.  S202 works
similarly to S2 except that the S2 escape character is used in the escape
sequence from on-line to the command mode.Range: 0-255, ASCII decimal
Default: 170 (Escape disabled)

A value over 127 disables the escape process, i.e., no escape character will
be recognized.  The default S202 value of 170 disables the escape process to
Remote Access (whereas the default S2 value enables escape to command mode).
If 128 is subtracted from 170 (i.e., bit 7 is reset), the resulting 42 is the
ASCII code for the "*" character.  The "*" character is commonly used as the
Remote Access escape character. The Remote Access escape sequence consists of
four characters with a fixed escape guard time of 1 second.  Only the
character selected by S202 is valid.  When the "*" is used for the escape
character, the escape sequence is "****".   The Remote Access escape sequence
works when the modems are connected in any mode (normal, LAPM or MNP) except
direct mode.  The modem on which the remote commands are typed (the "local
modem") does not need any special code associated with the remote
configuration.  The "remote modem" (whose configuration will be modified
remotely) must have Remote Configuration Mode (RCM) enabled (bit 6 of S80).

The escape sequence entered by the user on the local modem is recognized by
the remote modem, which then sends a message to the local modem prompting for
entry of the " remote password".  From then on, operation is similar to RCM
except for slight differences of presentation.  The remote modem will send a
">" prompt before each AT command.  The user must type the AT prefix before
the command(s), which is not required by RCM.  Several commands on the same
line can be accepted.   Some potentially hazardous AT commands are barred in
Remote Access: ATO, ATZ, AT&T, AT\B, AT*C, AT*L, AT*P, and ATZ (note that ATA
and ATD are automatically barred because the modem is already connected).

To exit Remote Access, enter command AT*X.  Upon exiting Remote Access, the
normal data link is re- established and the "CONNECT" message is issued to
the DTE. (note that in RCM, exit is to the command mode, but actually, in
both cases, return is to the previous state before entering Remote
Access/RCM).  AT*R and AT*E commands also operate the same as in RCM.
Remote Access can be exited by typing a remote ATH command. The connection
will be terminated and a "NO CARRIER" response will be issued from the local
modem to the DTE since the hangup was actually performed by the remote modem.

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