
MULTITECH SYSTEMS, INC.

MT1932PCS, MT1932PCSI

Modem Type                Data (synchronous/asynchronous)/Fax/Simultaneous
                          voice
Maximum Data Rate         19.2Kbps
Maximum Fax Rate          14.4Kbps
Data Bus                  External
Fax Class                 Class I & II
Data Modulation Protocol  Bell 103A/212A

                          ITU-T V.21, V.22, V.22bis, V.23, V.32, V.32bis

                          AT&T V.32terbo

                          Multitech MSP
Fax Modulation Protocol   ITU-T V.17, V.21CH2, V.27ter, V.29
Error                     MNP2-5, V.42, V.42bis
Correction/Compression

[Image]

                                CONNECTIONS

         Purpose           Location            Purpose           Location

  Handset in                  CN1       Headset in                 CN5

  Line out                    CN2       Microphone                 MIC

  RS-232/422                  CN3       Power switch               SW4

  DC power                    CN4

               DTR MODE

       Mode              SW1/1

    DTR normal             On

  DTR forced high         Off

                               FLOW CONTROL

          Mode                  Async/Sync                 SW1/2

  Hardware flow control           Async                     On

  Software flow control           Async                     Off

          SDLC                     Sync                     On

           BSC                     Sync                     Off

                    RESULT CODES and LINE ATTENUATION

          Mode               Switched/Leased               SW1/3

  Result codes enabled           Switched                   Off

  Result codes disabled          Switched                   On

     Transmit at 0dB              Leased                    Off

    Transmit at -10dB             Leased                    On

                       UUCP SPOOFING and AS/400 MODE

           Mode                  Async/Sync                 SW1/4

  UUCP spoofing disabled            Async                     On

  UUCP spoofing enabled             Async                    Off

     AS/400 disabled                Sync                      On

      AS/400 enabled                Sync                     Off

                   AUTO-ANSWER and ANSWER/ORIGINATE

          Mode              Switched/Leased             SW1/5

  Auto-answer enabled          Switched                   On

  Auto-answer disabled         Switched                  Off

      Answer mode               Leased                    On

     Originate mode             Leased                   Off

                      EFFICIENCY MODE and SLAVE CLOCK

            Mode                    Async/Sync               SW1/6

     Modem set to maximum             Async                    On
         efficiency

   Modem not set to maximum           Async                   Off
         efficiency

  Clock controlled remotely            Sync                    On

  Clock controlled locally             Sync                   Off

               RTS MODE

       Mode              SW1/7

  RTS forced high         Off

    RTS normal             On

                   COMMAND MODE

          Mode                    SW1/8

  Command mode enabled             Off

  Command mode disabled             On

            LOOPBACK MODE

       Mode              SW1/9

  Remote loopback         Off

  Local loopback           On

             LINE TYPE

    Type      SW1/10       SW5

  Switched      On          On

   Leased       Off        Off

                     RESULT CODE TYPE and CLOCK SOURCE

           Mode                  Async/Sync                 SW1/11

  Multitech result codes            Async                    Off

     AT result codes                Async                     On

      Internal clock                Sync                     Off

      External clock                Sync                      On

  ASYNCHRONOUS/SYNCHRONOUS MODE

      Mode            SW1/12

  Asynchronous          Off

   Synchronous          On

          OPERATION SPEED

   Speed       SW2/1      SW2/2

  19.2Kbps      On          On

  14.4Kbps      Off         On

  9600bps       On         Off

  2400bps       Off        Off

                    CD/DSR MODE

           Mode                     SW2/3

    CD and DSR normal                On

  CD and DSR forced high             Off

  FACTORY CONFIGURED - DO NOT ALTER

      Switch            Position

       SW2/4               N/A

                             DIAGNOSTIC LED(S)

     LED         Color        Status                 Condition

     SD           Red           On          Modem is transmitting data

     SD           Red           Off       Modem is not transmitting data

     RD           Red           On            Modem is receiving data

     RD           Red           Off         Modem is not receiving data

     CD           Red           On            Carrier signal detected

     CD           Red           Off         Carrier signal not detected

    19.2          Red           On          Modem connected at 19.2Kbps

    19.2          Red           Off       Modem not connected at 19.2Kbps

    14.4          Red           On          Modem connected at 14.4Kbps

    14.4          Red           Off       Modem not connected at 14.4Kbps

     96           Red           On          Modem connected at 9600bps

     96           Red           Off       Modem not connected at 9600bps

     96           Red           On          Modem connected at 9600bps

     96           Red           Off       Modem not connected at 9600bps

     24           Red           On          Modem connected at 2400bps

     24           Red           Off       Modem not connected at 2400bps

     12           Red           On          Modem connected at 1200bps

     12           Red           Off       Modem not connected at 1200bps

     OH           Red           On               Modem is off-hook

     OH           Red           Off              Modem is on-hook

     TR           Red           On              DTR signal is high

     TR           Red           Off              DTR signal is low

     EC           Red           On           Error correction enabled

     EC           Red           Off          Error correction disabled

     EC           Red        Blinking       Error correction activated

     FX           Red           On        Modem is connected in FAX mode

     FX           Red           Off        Modem is not connected in FAX
                                                       mode

                         Proprietary AT Command Set

                         AMBIENT NOISE SENSITIVITY

  Type:           Configuration

  Format:         AT [cmds] >HVn [cmds]

  Example:        AT >HV10 >C0<CR>

  Default:        7

  Range:          0-14

  Description:    Sets the modems sensitivity to ambient noise, with 0
                  being the most sensitive.

                  AUTO-RELIABLE TIME BUFFER CONFIGURATION

  Type:          Configuration

  Format:        AT [cmds] $An [cmds]

  Example:       AT $A1 &W<CR>

  Description:   Controls the handling of incoming data during
                 auto-reliable time period.

    Command                              Function

      $A0        Data is discarded.

      $A1        Data is buffered.

                                 BIT MODE

  Type:          Configuration

  Format:        AT [cmds] $EBn [cmds]

  Example:       AT $EB1 E1<CR>

  Description:   Selects 10- or 11-bit mode.

    Command                              Function

      $EB0       Sets 10-bit mode.

      $EB1       Sets 11-bit mode.

                             CALLBACK ATTEMPTS

  Type:          Register

  Format:        AT [cmds] S16=n [cmds]

  Example:       ATS16=6<CR>

  Default:       4

  Range:         1-255

  Unit:          1 attempt

  Description:   Sets the maximum number of login attempts after initial
                 callback connection.

                              CALLBACK NUMBER

  Type:               Configuration

  Format:             AT [cmds] [+/-]DT<#>Nnn

  Examples:           AT#DB2 +-DT555-1212N10<CR>

  Description:        Sets the phone number associated with the password
                      at memory location nn.

       Command                             Function

         +DT          Modem will initiate callback on successful login.

         -DT          Modem will allow immediate entry on successful
                      login without callback.

        +-DT          If password is followed by a -, modem will allow
                      immediate entry. If password is followed by a + or
                      nothing, modem will initiate callback.

                              CALLBACK PARITY

  Type:          Configuration

  Format:        AT [cmds] #Pn [cmds]

  Example:       AT #P0 #DB1<CR>

  Description:   Sets the parity of the modem when in callback mode.

    Command                              Function

      #P0        No parity.

      #P1        Odd parity.

      #P2        Even parity.

                             CALLBACK PASSWORD

  Type:                Configuration

  Format:              AT [cmds] #CBNnnxxxx

  Example:             AT#DB2 #CBN09snarf<CR>

  Description:         Sets the callback password at memory location nn
                       to xxxx. The password must be between 6 and 10
                       characters, inclusive.

                             CALLBACK SECURITY

  Type:          Configuration

  Format:        AT [cmds] #DBn [cmds]

  Example:       AT #DB1 S0=1<CR>

  Description:   Sets the security level of the callback function.

    Command                              Function

      #DB0       Disables security and clears callback memory.

      #DB1       Enables remote security only.

      #DB2       Enables local and remote security.

                            COMMAND ESCAPE TYPE

  Type:          Configuration

  Format:        AT [cmds] %En [cmds]

  Example:       AT %E3 &W<CR>

  Description:   Sets type and response of command escape sequence.

    Command                              Function

      %E0        Command escape disabled.

      %E1        TIES escape (+++AT...)

      %E2        <BREAK>AT method.

      %E3        Both TIES and BREAK methods.

      %E4        OK response to command escape disabled.

      %E5        OK response to command escape enabled.

                                COMMAND SET

  Type:          Configuration

  Format:        AT &Qn

  Example:       AT &Q1<CR>

  Description:   Selects standard Hayes or custom command sets.

    Command                              Function

      &Q0        Multi-Tech custom command set enabled.

      &Q1        Standard Hayes command set enabled.

                                COMPRESSION

  Type:          Configuration

  Format:        AT &En

  Example:       AT &E15 #L0<CR>

  Description:   Selects data compression.

    Command                              Function

      &E14       Data compression disabled.

      &E15       Data compression enabled.

                             COMPRESSION MODE

  Type:          Configuration

  Format:        AT #Ln

  Example:       AT #L2 DT555-1212<CR>

  Description:   Selects active compression protocols.

    Command                              Function

      #L0        V.42 negotiation enabled.

      #L1        MNP negotiation enabled.

      #L2        LAP-M negotiation enabled.

      #L3        LAP-M enabled, no negotiation.

                                CTS SIGNAL

  Type:          Configuration

  Format:        AT [cmds] &RFn [cmds]

  Example:       AT &RF0<CR>

  Description:   Selects the function of the CTS signal.

    Command                              Function

      &RF0       CTS is set to RTS.

      &RF1       CTS is independent of RTS.

                              DETECTION MODE

  Type:          Configuration

  Format:        AT [cmds] >DTn [cmds]

  Example:       AT >DT1<CR>

  Description:   Sets the responses the modem will detect.

    Command                              Function

      >DT0       Detection disabled.

      >DT1       DTMF detection enabled.

      >DT2       All signals will be detected.

                         DIAL STORED PHONE NUMBER

  Type:                 Immediate

  Format:               AT [cmds] Nn1 [Nn2, Nn3...]

  Example:              ATM0 N1N3N5<CR>

  Description:          Dials stored phone number(s). If the first number
                        is busy, the modem will proceed to the next
                        number in the list.

                               DIALING MODE

  Type:          Configuration

  Format:        AT [cmds] $VDn [cmds]

  Example:       AT $VD <CR>

  Description:   Selects voice/data mode dialing.

    Command                              Function

      $VD0       Disables voice/data mode.

      $VD1       Enables voice/data mode.

                                 DSP INPUT

  Type:          Configuration

  Format:        AT [cmds] >DIn [cmds]

  Example:       AT >DI4 >DO6<CR>

  Description:   Sets the input source of the digital signal processor.

    Command                              Function

      >DI0       Input disabled.

      >DI1       Input from line in.

      >DI2       Input from handset.

      >DI3       Input from phone.

      >DI4       Input from PC.

      >DI5       Input from voicemail.

      >DI6       Input from Digital Simultaneous Voice Mode session.

                                DSP OUTPUT

  Type:          Configuration

  Format:        AT [cmds] >DOn [cmds]

  Example:       AT >DI5 >DO3<CR>

  Description:   Sets the output device of the digital signal processor.

    Command                              Function

      >DO0       Output disabled.

      >DO1       Output to line out.

      >DO2       Output to handset.

      >DO3       Output to phone.

      >DO4       Output to PC.

      >DO5       Output to voicemail.

      >DO6       Output to Digital Simultaneous Voice Mode session.

                                DSR SIGNAL

  Type:          Configuration

  Format:        AT [cmds] &SFn [cmds]

  Example:       AT &SF0<CR>

  Description:   Selects the function of the DSR signal.

    Command                              Function

      &SF0       DSR is set to CD.

      &SF1       DSR is independent of CD.

                         DSVD TALK ANYTIME&trade;

  Type:          Configuration

  Format:        AT [cmds] >Cn [cmds]

  Example:       AT >C1 O<CR>

  Description:   Enables DSVD (Digital Simultaneous Voice Data)
                 connection.

    Command                              Function

      >C0        Talk Anytime&trade; enabled.

      >C1        Talk Anytime&trade; disabled.

                                   DSVD

  Type:          Immediate

  Format:        AT [cmds] >VDn [cmds]

  Example:       AT >VD1 O<CR>

  Description:   Activates DSVD (Digital Simultaneous Voice Data)
                 connection.

    Command                              Function

      >VD0       Deactivates DSVD.

      >VD1       Activates DSVD.

                                DTR DIALING

  Type:          Configuration

  Format:        AT [cmds] $Dn [cmds]

  Example:       AT $D1 DT555-1212<CR>

  Description:   Turns DTR dialing on and off.

    Command                              Function

      $D0        DTR dialing disabled.

      $D1        DTR dialing enabled.

                                DTR TIMEOUT

  Type:          Register

  Format:        AT [cmds] S24=n [cmds]

  Example:       ATS24=40<CR>

  Default:       20

  Range:         0-255

  Unit:          50 ms

  Description:   Sets the time to drop the DTR signal to hangup.

                          ERASE CALLBACK PASSWORD

  Type:          Immediate

  Format:        AT [cmds] #RCBNn [cmds]

  Example:       AT #RCBN05 #RDN05<CR>

  Description:   Erases the callback password at the memory location
                 specified.

                           ERASE CALLBACK NUMBER

  Type:          Immediate

  Format:        AT [cmds] #RDNn [cmds]

  Example:       AT #RCBN05 #RDN05<CR>

  Description:   Erases the callback phone number at the memory location
                 specified.

                    ERROR CORRECTION DISABLE ON CONNECT

  Type:          Configuration

  Format:        AT [cmds] $Fn [cmds]

  Example:       AT $F1 DT555-1212<CR>

  Description:   Selects whether error correction can be disabled by a
                 <CR> while handshaking.

    Command                              Function

      $F0        Error correction handshake interrupt disabled.

      $F1        Error correction handshake interrupt enabled.

                        ESCAPE SEQUENCE BUFFER SIZE

  Type:          Register

  Format:        AT [cmds] S34=n [cmds]

  Example:       ATS34=30<CR>

  Default:       10

  Range:         0-60

  Unit:          1 byte

  Description:   Sets the size of the buffer used to store commands
                 during an escape sequence.

                       ESCAPE SEQUENCE - OUT OF BAND

  Type:          Immediate

  Format:        <BREAK> AT [cmds]<CR>

  Example:       <BREAK> AT #F1<CR>

  Description:   Puts the modem in Command Mode.

  Notes:         Do not precede this command with AT.

                 <BREAK> refers to the hardware modem break signal.

                          ESCAPE SEQUENCE TIMEOUT

  Type:              Register

  Format:            AT [cmds] S32=n [cmds]

  Example:           ATS32=30<CR>

  Default:           20

  Range:             0-255

  Unit:              1 second

  Description:       Sets the maximum amount of time the modem will wait
                     for a <CR> while executing an escape sequence.

                             FACTORY DEFAULTS

  Type:          Immediate/Configuration

  Format:        AT &F[n]

  Example:       AT &F8<CR>

  Description:   Loads factory defaults, or sets write protect on NVRAM.

    Command                              Function

       &F        Reloads defaults by setting. (Immediate, see below.)

      &F8        Sets &F to read factory defaults from ROM, and disables
                 NVRAM write protect.

      &F9        Sets &F to read defaults from NVRAM, and enables
                 write-protect.

                         FAILED PASSWORD ATTEMPTS

  Type:          Register

  Format:        AT [cmds] S26?

  Example:       ATS26?<CR>

  Default:       Read-only

  Range:         0-255

  Unit:          1 attempt

  Description:   This register stores the number of failed password
                 attempts.

                               FALLBACK MODE

  Type:          Configuration

  Format:        AT [cmds] #Fn [cmds]

  Example:       AT #F1 O<CR>

  Description:   Sets direction of fallback.

    Command                              Function

      #F0        Fallback disabled.

      #F1        Fallback from 19.2Kbps to 2400bps as line quality
                 degrades.

      #F2        Fallback from 2400bps to 19.2Kbps as line quality
                 improves.

                         FLOW CONTROL NORMAL MODE

  Type:          Configuration

  Format:        AT [cmds] &En [cmds]

  Example:       AT &E11 O<CR>

  Description:   Selects normal flow control.

    Command                              Function

      &E10       Normal mode disabled.

      &E11       Normal mode enabled.

                             FLOW CONTROL TYPE

  Type:          Configuration

  Format:        AT [cmds] &En [cmds]

  Example:       AT &E4 &W<CR>

  Description:   Sets type of flow control used by modem.

    Command                              Function

      &E3        Flow control disabled.

      &E4        CTS/RTS flow control enabled.

      &E5        XON/XOFF flow control enabled.

                            HANDSHAKE ATTEMPTS

  Type:             Configuration

  Format:           AT [cmds] #An [cmds]

  Example:          AT #A1 #L3<CR>

  Description:      Configures the initial handshake phase.

     Command                              Function

       #A0          Attempts in order: 19.2Kbps, 14.4Kbps, 12Kbps,
                    9600bps, 4800bps, 2400bps, 1200bps, 300bps.

       #A1          Attempts only 19.2Kbps.

       #A2          Attempts in order: 19.2Kbps, 14.4Kbps, 12Kbps,
                    9600bps, 4800bps.

       #A3          Attempts in order: 2400bps, 1200bps, 300bps.

                               HELP SCREENS

  Type:          Immediate

  Format:        AT $Hn

  Example:       AT $H1<CR>

  Description:   Shows modem help screens.

    Command                              Function

      $H1        Shows help screen 1.

      $H2        Shows help screen 2.

      $H3        Shows help screen 3.

                            LIST CONFIGURATION

  Type:          Immediate

  Format:        AT Ln

  Example:       AT L5<CR>

  Description:   Lists modem configuration.

    Command                              Function

       L5        Lists all settings.

       L6        Lists the values of all S-registers.

       L7        Lists extended parameters.

       L8        Lists current diagnostics.

                              LINE CONNECTION

  Type:          Configuration

  Format:        AT [cmds] >PHn [cmds]

  Example:       AT >PH1<CR>

  Description:   Selects the operation mode of the modem.

    Command                              Function

      >PH0       Modem is in data mode.

      >PH1       Modem is in voice mode.

                          LOCAL SERIAL PORT SPEED

  Type:          Configuration

  Format:        AT [cmds] $SBnnn [cmds]

  Example:       AT $MB9600 $SB19200<CR>

  Description:   Sets serial port speed.

    Command                              Function

     $SB300      Sets 300bps speed.

    $SB1200      Sets 1200bps speed.

    $SB2400      Sets 2400bps speed.

    $SB4800      Sets 4800bps speed.

    $SB9600      Sets 9600bps speed.

    $SB19200     Sets 19.2Kbps speed.

    $SB38400     Sets 38.4Kbps speed.

    $SB57600     Sets 57.6Kbps speed.

   $SB115200     Sets 115.2Kbps speed.

                             LOCK SERIAL PORT

  Type:          Configuration

  Format:        AT [cmds] $BAn [cmds]

  Example:       AT $SB57600 $BA0<CR>

  Description:   Sets operation of serial port speed.

    Command                              Function

      $BA0       Serial speed locked at rate set by $SB.

      $BA1       Serial speed follows connect speed, ignoring $SB.

                              LOGIN PASSWORD

  Type:                Configuration

  Format:              AT [cmds] #Ixxxx

  Example:             AT #IMicroHouse<CR>

  Description:         Sets the login password to xxxx. The password must
                       be between 6 and 10 characters, case sensitive. It
                       defaults to MULTI-TECH.

                    MAXIMUM BLOCK SIZE FOR TRANSMISSION

  Type:          Configuration

  Format:        AT [cmds] &BSn [cmds]

  Example:       AT &BS1 &MB28800<CR>

  Description:   Sets the maximum transmittable block size.

    Command                              Function

      &BS0       Maximum block size is 64 characters.

      &BS1       Maximum block size is 128 characters for LAP-M, and 256
                 characters for MNP.

                                MICROPHONE

  Type:          Configuration

  Format:        AT [cmds] >Mn>MVn [cmds]

  Example:       AT >M2>MV5<CR>

  Description:   Turns the microphone of the attached telephone handset
                 on or off.

  Note:          An >MV command must be issued on the same line.

    Command                              Function

      >M0        Disables microphone.

      >M2        Enables microphone.

                          MICROPHONE SENSITIVITY

  Type:          Configuration

  Format:        AT [cmds] >MVn [cmds]

  Example:       AT >MV6<CR>

  Default:       None

  Range:         0-14

  Description:   Sets the microphones sensitivity, with 0 being the most
                 sensitive.

                                 MSP MODE

  Type:          Configuration

  Format:        AT [cmds] %Pn [cmds]

  Example:       AT %P1<CR>

  Description:   Enables or disables Multitech Supervisory Protocol
                 (MSP).

    Command                              Function

      %P0        MSP disabled.

      %P1        MSP enabled.

                                  PACING

  Type:          Configuration

  Format:        AT [cmds] &En [cmds]

  Example:       AT &E13<CR>

  Description:   Selects ENQ/ACK pacing.

    Command                              Function

      &E12       Disables ENQ/ACK pacing.

      &E13       Enables ENQ/ACK pacing.

                             PACING - ENQ/ACK

  Type:          Configuration

  Format:        AT [cmds] &En [cmds]

  Example:       AT &E9<CR>

  Description:   Selects ENQ/ACK pacing.

    Command                              Function

      &E8        Enables ENQ/ACK pacing.

      &E9        Disables ENQ/ACK pacing.

                                  REDIAL

  Type:          Immediate

  Format:        ATA:

  Example:       ATA:<CR>

  Description:   Redials the last number dialed until it is no longer
                 busy.

                           REMOTE CONNECT SPEED

  Type:          Configuration

  Format:        AT $MBnnn

  Example:       AT $MB9600 $SB19200<CR>

  Description:   Sets maximum remote connect speed.

    Command                              Function

     $MB75       Sets V.23 (1200bps/75bps bi-directional).

     $MB300      Sets 300bps connect.

    $MB1200      Sets 1200bps connect.

    $MB2400      Sets 2400bps connect.

    $MB4800      Sets 4800bps connect.

    $MB9600      Sets 9600bps connect.

    $MB14400     Sets 14.4Kbps connect.

    $MB19200     Sets 19.2Kbps connect.

                          RETRANSMIT FAIL ACTION

  Type:          Configuration

  Format:        AT [cmds] $Rn [cmds]

  Example:       AT $R1<CR>

  Description:   Sets whether the modem gives up on a bad connection.

    Command                              Function

      $R0        Hang up after 12 failed retransmissions.

      $R1        Do not hang up after 12 failed retransmissions.

                          SETUP INACTIVITY TIMER

  Type:             Register

  Format:           AT [cmds] S29=n [cmds]

  Example:          ATS29=5<CR>

  Default:          20

  Range:            1-255

  Unit:             1 minute

  Description:      Sets the maximum amount of time between commands
                    until the setup password must be re-entered.

                                  SPEAKER

  Type:          Configuration

  Format:        AT [cmds] >Sn>SVn [cmds]

  Example:       AT >S2>SV5<CR>

  Description:   Turns the speaker of the attached telephone handset on
                 or off.

  Note:          An >SV command must be issued on the same line.

    Command                              Function

      >S0        Disables speaker.

      >S2        Enables speaker.

                              SPEAKER VOLUME

  Type:          Configuration

  Format:        AT [cmds] >SVn [cmds]

  Example:       AT >SV6<CR>

  Default:       None

  Range:         0-14

  Description:   Sets the speakers volume, with 0 being the most
                 sensitive.

                        STORE PHONE NUMBER IN NVRAM

  Type:          Configuration

  Format:        AT [cmds] D<#>Nn [dialstring]

  Example:       ATD555-1212N1<CR>

  Description:   Stores a phone number in the modems memory.

                       TIME UNTIL HANG UP ON LOW DTR

  Type:             Register

  Format:           AT [cmds] S36=n [cmds]

  Example:          ATS36=5<CR>

  Default:          0

  Range:            0-255

  Unit:             1 second

  Description:      Sets the maximum amount of time the modem will wait
                    to hang up after the DTR signal goes low.

                      TIME UNTIL PICK UP ON HIGH DTR

  Type:             Register

  Format:           AT [cmds] S37=n [cmds]

  Example:          ATS37=5<CR>

  Default:          0

  Range:            0-255

  Unit:             1 second

  Description:      Sets the maximum amount of time the modem will wait
                    to pick up after the DTR signal goes high.

                            TRELLIS MODULATION

  Type:          Configuration

  Format:        AT [cmds] #Tn [cmds]

  Example:       AT #T1<CR>

  Description:   Controls Trellis Coded Modulation.

    Command                              Function

      #T0        Disables TCM.

      #T1        Enables TCM.

                                 V.25 MODE

  Type:           Configuration

  Format:         AT [cmds] $Vn [cmds]

  Example:        AT $V2 CIC<CR>

  Description:    Configures V.25bis mode.

    Command                              Function

      $V0         Disables V.25bis.

      $V1         Enables V.25bis.

      $V2         Modem will accept one V.25bis command and will then
                  return to AT command mode.

      $V5         DSR follows DTR in V.25bis command mode.

      $V6         DSR operates normally in V.25bis command mode.

                             V.32terbo CONTROL

  Type:          Configuration

  Format:        AT [cmds] #Vn [cmds]

  Example:       AT #V1 DT555-1212<CR>

  Description:   Controls the V.32terbo protocol in answer mode.

    Command                              Function

      #V0        V.32terbo enabled.

      #V1        V.32terbo disabled.

                                 V.42 MODE

  Type:          Configuration

  Format:        AT [cmds] &En [cmds]

  Example:       AT &E0 <CR>

  Description:   Configures the operation of V.42 mode.

    Command                              Function

      &E0        Error correction disabled.

      &E1        V.42 set to auto-reliable.

      &E2        V.42 set to reliable.

                              VOICE BANDWIDTH

  Type:          Configuration

  Format:        AT [cmds] >An [cmds]

  Example:       AT >A0 <CR>

  Description:   Sets the bandwidth reserved for voice transmission.

    Command                              Function

      >A0        Voice bandwidth set to 9600bps.

      >A1        Voice bandwidth set to 16Kbps.

                                 XOFF SEND

  Type:          Configuration

  Format:        AT [cmds] #Xn [cmds]

  Example:       AT #X1<CR>

  Description:   Selects how XOFF signal is sent.

    Command                              Function

      #X0        Single XOFF character sent until ready.

      #X1        Multiple XOFF characters sent until ready.

                           XON/XOFF PASS-THROUGH

  Type:          Configuration

  Format:        AT [cmds] &En [cmds]

  Example:       AT &E7 O<CR>

  Description:   Selects whether XON/XOFF signals are sent to remote
                 modem.

    Command                              Function

      &E6        XON/XOFF signals trapped by local modem.

      &E7        XON/XOFF passed through local modem.

                      Proprietary V.25bis Command Set

                           CLEAR MEMORY LOCATION

  Type:          Immediate

  Format:        CLAn

  Example:       CLA05<CR>

  Description:   Clears the phone number in memory location nn.

                          LOCAL SERIAL PORT SPEED

  Type:          Configuration

  Format:        CSPn

  Example:       CSP38400<CR>

  Description:   Sets serial port speed.

    Command                              Function

     CSP300      Sets 300bps speed.

    CSP1200      Sets 1200bps speed.

    CSP2400      Sets 2400bps speed.

    CSP4800      Sets 4800bps speed.

    CSP9600      Sets 9600bps speed.

    CSP19200     Sets 19.2Kbps speed.

    CSP38400     Sets 38.4Kbps speed.

    CSP57600     Sets 57.6Kbps speed.

   CSP115200     Sets 115.2Kbps speed.

                           CALL REQUESTED NUMBER

  Type:               Immediate

  Format:             CRI<#>;n

  Example:            CRI1-303 555-1212;fubar<CR>

  Description:        Same as CRN. Dials the number given. It will ignore
                      spaces and hyphens in the string. If the string is
                      more than fifty characters long, a result of INV
                      will be returned. The identification string n will
                      be ignored.

                          REQUEST LISTED NUMBERS

  Type:             Immediate

  Format:           RLN

  Example:          RLN<CR>

  Description:      Requests the modem to return the list of stored
                    numbers. If no numbers are stored, the modem will
                    return LSN.

