
3COM CORPORATION

COURIER HST DUAL STANDARD W/ V.32BIS & ASL

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

                             ITU-T V.22, V.22bis, V.23, V.32, V.32bis
Error Correction/Compression MNP5, V.42, V.42bis

[Image]

                                CONNECTIONS

         Purpose             Location          Purpose           Location

  Line out                     CN1       DC power                  CN4

  Line in                      CN2       Volume                    R1

  RS-232/422                   CN3       Power switch              SW2

                       MI/MIC POLARITY

  Setting                     J6                  J8

   Normal             Pins 1 & 2 closed   Pins 1 & 2 closed

  Reversed             Pins 2 & 3 closed   Pins 2 & 3 closed

                       TX/RX PIN ASSIGNMENT

  Setting                                      SW3

        Normal operation           Off

  Reverse TX/RX pin assignments   On

              DTR SIGNAL

  Setting                SW1/1

  DTR forced high          On

   DTR normal            Off

                            RESULT CODES

  Setting                                       SW1/2

   Verbose result codes enabled                 Off

  Numeric result codes enabled                   On

           RESULT CODES DISPLAY

  Setting                   SW1/3

   Display enabled           On

  Display disabled           Off

             ECHO COMMANDS DISPLAY

  Setting                        SW1/4

   Local echo enabled            Off

  Local echo disabled             On

                                AUTO ANSWER

  Setting                                             SW1/5

   Modem answers on first ring                        On

  Modem does not answer on first ring                  Off

           CARRIER DETECT

  Setting               SW1/6

   CD normal            Off

  CD forced high         On

                           RESULT CODES DISPLAY

  Setting                                             SW1/7

   Display result codes in originate                  Off
  and answer modes

  Display result codes in Answer mode                   On

                     AT COMMAND SET

  Setting                              SW1/8

   AT command set enabled              On

  AT command set disabled               Off

                                ESCAPE CODE

  Setting                                           SW1/9

   Off                               Disconnect, go to command mode and
                                        display NO CARRIER when escape
                                            character is received

  On                                   Go to command mode and display OK
                                     result code when escape character is
                                                   received

                 USER PROFILE

  Setting                      SW1/10

   Off                  Use stored profile

  On                    Use factory default

                        VOICE/DATA

           Setting                        SW4

  Note: for switch functions see table for register S32.

                             DIAGNOSTIC LED(S)

    LED        Color         Status                  Condition

    HS          Red            On          Modem is operating at 4800bps
                                                     or faster

    HS          Red            Off          Modem is operating at slower
                                                   than 4800bps

    AA          Red            On               Auto-answer enabled

    AA          Red            Off             Auto-answer disabled

    CD          Red            On             Carrier signal detected

    CD          Red            Off          Carrier signal not detected

    OH          Red            On                Modem is off-hook

    OH          Red            Off               Modem is on-hook

    RD          Red            On             Modem is receiving data

    RD          Red            Off          Modem is not receiving data

    TD          Red            On           Modem is transmitting data

    TD          Red            Off        Modem is not transmitting data

    TR          Red            On               DTR signal is high

    TR          Red            Off               DTR signal is low

    MR          Red            On                   Power is on

    MR          Red            Off                 Power is off

    MR          Red         Blinking       Modem is retraining or in test
                                                       mode

    RS          Red            On               RTS signal is high

    RS          Red            Off               RTS signal is low

    CS          Red            On               CTS signal is high

    CS          Red            Off               CTS signal is low

    EC          Red            On              Error control enabled

    EC          Red            Off            Error control disabled

    EC          Red         Blinking       Modem is retransmitting data

    SYN         Red            On                Synchronous mode

    SYN         Red            Off               Asynchronous mode

                         Proprietary AT Command Set

                          BIT-MAPPED REGISTER S13

  Format                     AT [cmds] S13=n [cmds]

  Example:                   ATS13=139<CR>

  Default:                   0

  Range:                     0 - 255

  Unit:                      Bit-mapped

  Description:               Controls DTR reset, DTR dialing, auto
                             answer, result code delay, reset dialing,
                             HST and MNP3.

       Bit          Value                       Function

        0            0         DTR normal.

                    1           Reset on low DTR.

        1            0         Auto answer operation normal.

                    1           When ring detected, enter originate mode
                                and listen for answer tone.

        2            0         Pause 250 msec. before displaying result
                                codes.
                    1
                                Display result codes immediately.

        3            0         DTR dialing disabled.

                    1           DTR dialing enabled.

        4            0         Reset dialing disabled.

                    1           Reset dialing enabled.

        5            0         HST enabled.

                    1           HST disabled.

        6            0         MNP 3 enabled.

                    1           MNP 3 disabled.

                          BIT-MAPPED REGISTER S15

  Format:                   AT [cmds] S15=n [cmds]

  Example:                  ATS15=139<CR>

  Default:                  0

  Range:                    0 - 255

  Unit:                     Bit-mapped

  Description:              Controls HST high frequency equalization,
                            online fallback, back channel,
                            non-error-correcting mode buffer, MNP4,
                            BS/DEL switch, and MNP compliance.

       Bit          Value                       Function

        0            0        HST high frequency equalization enabled.

                    1          HST high frequency equalization disabled.

        1            0        Online fallback enabled.

                    1          Online fallback disabled.

        2            0        450bps back channel enabled.

                    1          450bps back channel disabled.

        3            0        Non-error-correcting mode transmit buffer
                               set to 1.5KB.
                    1
                               Non-error-correcting mode transmit buffer
                               set to 128 bytes.

        4            0        MNP 4 enabled.

                    1          MNP 4 disabled.

        5            0        Use backspace key for delete disabled.

                    1          Use backspace key for delete enabled.

        6            0        MNP normal.

                    1          MNP adjusted for non compliant modems.

        7            0        Proprietary network compatibility
                               disabled.
                    1
                               Proprietary network compatibility 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, and 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.

       5, 4           00       V.42 detect, LAPM and MNP enabled.

                     01         V.42 detect and LAPM enabled.

                     10         MNP enabled.

                     11         LAPM enabled.

         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:         Unidentified

  Unit:          10 ms

  Description:   Sets the length of error control 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.

                                COMPRESSION

  Type:          Configuration

  Format:        AT [cmds] &Kn [cmds]

  Example:       AT &K1<CR>

  Description:   Controls data compression.

  Command                                Function

  &K0            Data compression disabled.

   &K1          Data compression disabled when serial port is locked.

  &K2            MNP5 enabled/MNP4 enabled.

  &K3            MNP 5 disabled.

                       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

                           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 - XON

  Type:          Register

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

  Example:       ATS22=20<CR>

  Default:       17

  Range:         11-127

  Unit:          ASCII

  Description:   Sets the character used to represent XON.

                       FLOW CONTROL CHARACTER - XOFF

  Type:          Register

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

  Example:       ATS23=20<CR>

  Default:       19

  Range:         11-127

  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.

  &I3            ENQ/ACK protocol used in host mode.

  &I4            ENQ/ACK protocol used in terminal mode.

  &I5            XON/XOFF passthrough disabled in ARQ mode, XON/XOFF to
                 remote modem.

                             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 AT help screen.

         &$            Shows AT& help screen.

         D$            Shows ATD help screen.

         S$            Shows S-register help screen.

                             INACTIVITY TIMER

  Type:             Register

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

  Example:          ATS19=20<CR>

  Default:          0

  Range:            Unidentified

  Unit:             1 minute

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

                              NETWORK ACCESS

  Type:          Configuration

  Format:        AT [cmds] %Rn [cmds]

  Example:       AT %R1 &W<CR>

  Description:   Used with USR network management system.

  Command                                Function

   %R0          Network access disabled.

  %R1            Network access enabled.

                           REPEAT COMMAND STRING

  Type:          Configuration

  Format:        AT [cmds] > [cmds]

  Example:       AT *D1 > #E1<CR>

  Description:   Causes modem to repeat command string until a keyboard
                 key is pressed.

                            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 call duration.

       I4        Reports current command settings.

       I5        Reports current NVRAM settings.

       I6        Reports current connections statistics.

       I7        Reports configuration.

                            STATUS REGISTER BIT

  Type:          Configuration

  Format:        Read: AT [cmds] Sn.m=0 or 1 [cmds]

                 Write: AT [cmds] Sn.m=? [cmds]

  Example:       AT S40.4=1 S51.3?<CR>

  Description:   Sets/clears or reads bit m of register n.

                                TEST MODES

  Format              AT [cmds] S16=n [cmds]

  Example:            ATS16=32<CR>

  Default:            0

  Range:              0 - 15

  Unit:               Bit-mapped

  Description:        Enables loopback tests.

     Bit       Value                        Function

      0         0      Analog loopback test disabled.

               1        Analog loopback test enabled.

      1         0      Dial test disabled.

               1        Dial test enabled.

      2         0      Test pattern disabled.

               1        Test pattern enabled.

      3.        0      Remote digital loopback test disabled.

               1        Remote digital loopback test enabled.

                               TIME DISPLAY

  Type:          Immediate

  Format:        AT [cmds] Kn [cmds]

  Example:       AT K1 *L2 #E1<CR>

  Description:   Displays the current call time or clock time.

  Command                                Function

   K0           Display length of last call.

  K1             Display actual time.

                          TOUCH TONE RECOGNITION

  Type:          Configuration

  Format:        AT [cmds] %Tn [cmds]

  Example:       AT %T &W<CR>

  Description:   Controls recognition of touch tones while off hook.

                       V.32 AND V.32bis MODULATIONS

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

  Example:            ATS34=139<CR>

  Default:            6

  Range:              0 - 63

  Unit:               Bit-mapped

  Description:        Controls V.32 and V.32bis modulations.

     Bit        Value                       Function

      0         0      V.32bis enabled.

               1        V.32bis disabled.

      1         0      Enhanced V.32bis enabled.

               1        Enhanced V.32bis disabled.

      2         0      Enhanced V.32bis retrain enabled.

               1        Enhanced V.32bis retrain disabled.

      3         0      V.23 disabled.

               1        V.23 enabled.

      4         0      MR LED normal.

               1        MR LED reflects DSR signal.

      5         0      MI/MIC disabled.

               1        MI/MIC 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.

                             VOICE/DATA SWITCH

  Type:          Register

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

  Example:       ATS32=6<CR>

  Default:       1

  Unit:          1-7

  Description:   Controls the function of SW4.

  Command                                Function

  0              Disabled.

   1            Switch between voice and originate mode.

  2              Switch between voice and answer mode.

  3              Redial.

  4              Dial number stored at position 0.

  5              Enable and disable Auto Answer.

  6              Reset.

  7              Start remote digital loopback test.

