
3COM CORPORATION

US ROBOTICS 14,400 EXTERNAL

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

                             ITU-T V.21, V.22, V.22bis, V.23, V.32,
                             V.32bis
Fax Modulation Protocol      ITU-T V.17, V.21CH2, V.27ter, V.29
Error Correction/Compression MNP5, V.42, V.42bis

[Image]

                                CONNECTIONS

         Purpose             Location          Purpose           Location

  Line out                     CN3       DC power                  CN1

  Line in                      CN4       Volume                    R1

  RS-232/422                   CN2       Power switch              SW2

              DTR SIGNAL

      Setting            SW1/1

    DTR normal            Off

  DTR forced high          On

                          RESULT CODES

            Setting                          SW1/2

  Verbal result codes enabled                 Off

  Numeric result codes enabled                On

  RESULT CODES DISPLAY

  Setting       SW1/3

  Enabled        On

  Disabled       Off

      ECHO DISPLAY

  Setting      SW1/4

  Enabled       Off

  Disabled      On

      AUTO ANSWER

  Setting      SW1/5

  Disabled      On

  Enabled       Off

           CARRIER DETECT

     Setting            SW1/6

    CD normal            Off

  CD forced high         On

                        SOFTWARE RESET

            Setting                        SW1/7

      Use stored profile                    Off

  Use factory default profile                On

     AT COMMAND SET

  Setting      SW1/8

  Enabled       On

  Disabled      Off

                             DIAGNOSTIC LED(S)

     LED       Color      Status       Mode             Condition

     AA         Red         On        Answer       Auto-answer enabled

     AA         Red        Off         N/A        Auto-answer disabled

     AA         Red      Blinking      N/A          Phone is ringing

     CD         Red         On         N/A       Carrier signal detected

     CD         Red        Off         N/A          Carrier signal not
                                                        detected

     RD         Red      Blinking      N/A       Modem is receiving data
                                                 or sending result codes

     RD         Red        Off         N/A        Modem is not receiving
                                                          data

     SD         Red      Blinking      N/A        Modem is transmitting
                                                          data

     SD         Red        Off         N/A      Modem is not transmitting
                                                          data

     TR         Red         On         N/A          DTR signal is low

     TR         Red        Off         N/A         DTR signal is high

     CS         Red         On         N/A              CTS high

     CS         Red        Off         N/A             CTS normal

   ARQ/FAX      Red         On         Data      Error control connection
                                                       established

   ARQ/FAX      Red      Blinking      Data       Error control data is
                                                    being transmitted

   ARQ/FAX      Red      Blinking      Fax      Modem is connected in FAX
                                                          mode

                         Proprietary AT Command Set

                          BIT-MAPPED REGISTER S13

  Format                    AT [cmds] S13=n [cmds]

  Example:                  ATS13=139<CR>

  Default:                  0

  Range:                    0 - 159

  Unit:                     Bit-mapped

  Description:              Controls DTR reset, DTR dialing, Transmit
                            buffer, backspace for delete, escape causes
                            disconnect.

       Bit          Value                      Function

        0              0      DTR normal.

                      1       Reset on low DTR.

        1              0      Non-error-correcting mode transmit buffer
                              set to 1.5KB.
                      1
                              Non-error-correcting mode transmit buffer
                              set to 128 bytes.

        2              0      Use backspace key for delete disabled.

                      1       Use backspace key for delete enabled.

        3              0      DTR dialing disabled.

                      1       DTR dialing enabled.

        4              0      Reset dialing disabled.

                      1       Reset dialing enabled.

        5             0       Not used.

        6             0       Not used.

        7              0      Escape code causes disconnect disabled.

                      1       Escape code causes disconnect enabled.

                          BIT-MAPPED REGISTER S27

  Format                     AT [cmds] S27=n [cmds]

  Example:                   ATS27=139<CR>

  Default:                   0

  Range:                     0 - 191

  Unit:                      Bit-mapped

  Description:               Controls V.21, V.32 encoding and modulation,
                             V.42 answer tone and handshake, V.32
                             fallback, V.32bis, 9600 result codes.

        Bit           Value                     Function

         0              0       V.21 disabled.

                        1       V.21 enabled.

         1              0       V.32 trellis coding disabled.

                        1       V.32 trellis coding enabled.

         2              0       V.32 modulation enabled.

                        1       V.32 modulation disabled.

         3              0       2100Hz answer tone enabled.

                        1       2100Hz answer tone disabled.

         4              0       V.32 fallback disabled.

                        1       V.32 fallback enabled.

         5              0       V.32bis enabled.

                        1       V.32bis disabled.

         6              0       Not used.

         7              0       Actual result codes displayed.

                        1       Force 9600 result codes.

                               BREAK LENGTH

  Type:          Register

  Format:        AT [cmds] S21=n [cmds]

  Example:       ATS21=20<CR>

  Default:       10

  Range:         0-255

  Unit:          10 milliseconds

  Description:   Sets the length of error correction mode breaks sent
                 from DCE to DTE.

                                BREAK TYPE

  Type:          Configuration

  Format:        AT [cmds] &Yn [cmds]

  Example:       AT &Y0<CR>

  Description:   Configures action of break signal.

    Command                              Function

      &Y0        Break empties buffer.

      &Y1        Break empties buffer and is sent immediately.

      &Y2        Break does not empty buffer and is sent immediately.

                       CONNECTION SPEED UPPER LIMIT

  Type:              Configuration

  Format:            AT [cmds] &Nn [cmds]

  Example:           AT &N1 DT555-1212<CR>

  Description:       Sets required connection speed if &U is set to 0.
                     Otherwise, sets fastest allowed connection speed.

      Command                              Function

        &N0          Variable.

        &N1          300bps

        &N2          1200bps

        &N3          2400bps

        &N4          4800bps

        &N5          7200bps

        &N6          9600bps

        &N7          12Kbps

        &N8          14.4Kbps

                           ERROR CORRECTION MODE

  Type:          Configuration

  Format:        AT [cmds] &Mn [cmds]

  Example:       AT &M1 %C1<CR>

  Description:   Selects active error correction protocols.

    Command                              Function

      &M0        Normal mode, error correction disabled.

      &M4        Normal/ARQ.

      &M5        ARQ mode.

                             ERROR CORRECTION

  Format              AT [cmds] S15=n [cmds]

  Example:            ATS15=139<CR>

  Default:            0

  Range:              0 - 255

  Unit:               Bit-mapped

  Description:        Controls error correction.

     Bit        Value                        Function

      0           0      V.22 error correction enabled.

                  1      V.22 error correction disabled.

      1           0      V.22bis error correction enabled.

                  1      V.22bis error correction disabled.

      2           0      V.32/V.32bis/V.32terbo error correction enabled.

                  1      V.32/V.32bis/V.32terbo error correction
                         disabled.

      3           0      MNP handshake enabled.

                  1      MNP handshake disabled.

      4           0      MNP 4 enabled.

                  1      MNP 4 disabled.

      5           0      MNP 3 enabled.

                  1      MNP 3 disabled.

      6           0      MNP incompatibility disabled.

                  1      MNP incompatibility enabled.

      7           0      V.42 enabled.

                  1      V.42 disabled.

                           EXTENDED RESULT CODES

  Type:          Configuration

  Format:        AT [cmds] &An [cmds]

  Example:       AT &A1 %C1<CR>

  Description:   Selects extended result codes.

    Command                              Function

      &A0        Extended result codes disabled.

      &A1        ARQ result codes enabled.

      &A2        V.32 result code enabled.

      &A3        Error control and compression result codes enabled.

                          FLOW CONTROL CHARACTER

  Type:          Register

  Format:        AT [cmds] S22=n [cmds]

  Example:       ATS22=20<CR>

  Default:       17

  Range:         0-127

  Unit:          ASCII

  Description:   Sets the character used to represent XON.

                          FLOW CONTROL CHARACTER

  Type:          Register

  Format:        AT [cmds] S23=n [cmds]

  Example:       ATS23=20<CR>

  Default:       19

  Range:         0-127

  Unit:          ASCII

  Description:   Sets the character used to represent XOFF.

                         FLOW CONTROL PASSTHROUGH

  Type:          Configuration

  Format:        AT [cmds] &In [cmds]

  Example:       AT &I0 &W<CR>

  Description:   Allows modem to act on, then transmit XON/XOFF
                 characters.

    Command                              Function

      &I0        Software flow control disabled.

      &I1        XON/XOFF passthrough enabled.

      &I2        XON/XOFF passthrough disabled.

                             FLOW CONTROL TYPE

  Type:          Configuration

  Format:        AT [cmds] &Hn [cmds]

  Example:       AT &H0 A<CR>

  Description:   Sets type of flow control used by modem.

    Command                              Function

      &H0        Flow control disabled.

      &H1        CTS/RTS flow control enabled.

      &H2        XON/XOFF flow control enabled.

      &H3        CTS/RTS and XON/XOFF flow control enabled.

                               HELP SCREENS

  Type:                Immediate

  Format:              AT <prefix>$

  Example:             AT &$<CR>

  Description:         Shows command help screens for all commands
                       beginning with the given prefix, or no prefix if
                       none is given.

       Command                              Function

          $            Shows ATx help screen.

         &$            Shows AT&x help screen.

                             INACTIVITY TIMER

  Type:             Register

  Format:           AT [cmds] S19=n [cmds]

  Example:          ATS19=20<CR>

  Default:          0

  Range:            0-255

  Unit:             1 minute

  Description:      Sets the length of time that the modem does not
                    receive information before it disconnects.

                             LOCK SERIAL PORT

  Type:          Configuration

  Format:        AT [cmds] &Bn [cmds]

  Example:       AT $ &B0<CR>

  Description:   Sets operation of serial port speed.

    Command                              Function

      &B0        Serial speed follows connect speed

      &B1        Serial speed locked.

      &B2        Serial speed locked in ARQ mode only,

                            REPORT INFORMATION

  Type:          Immediate

  Format:        AT [cmds] In [cmds]

  Example:       AT I1 O<CR>

  Description:   Displays modem properties.

    Command                              Function

       I0        Reports product code.

       I1        Reports ROM checksum result.

       I2        Reports RAM checksum result.

       I3        Reports firmware version.

       I4        Reports current command settings.

       I5        Reports current NVRAM settings.

       I6        Reports current connections statistics.

       I7        Reports configuration.

                             TONE DIALING TEST

  Format              AT [cmds] S16=n [cmds]

  Example:            ATS16=12<CR>

  Default:            0

  Range:              0 - 2

  Unit:               Bit-mapped

  Description:        Tone dialing test

     Bit       Value                        Function

      0          0      Not used.

      1           0     Tone dialing test disabled.

                 1      Tone dialing test enabled.

                            V.32 HANDSHAKE TIME

  Type:          Register

  Format:        AT [cmds] S28=n [cmds]

  Example:       ATS28=20<CR>

  Default:       8

  Range:         0-255

  Unit:          .1 second

  Description:   Sets length of V.32 handshake.



