
3COM CORPORATION

IMPACT (3C871, 3C876)

Card Type                    ISDN TA
I/O Options                  Analog adapter (optional)
Chipset                      Unidentified
Error Correction/Compression STAC
ISDN Transfer Rate           56Kbps x 2/64Kbps x 2
ISDN Protocol                V.120, PPP
Switch Type                  5ESS, DMS100, EWSD, NI-1
Data Bus                     Serial

[Image]

                                CONNECTIONS

         Function           Label             Function             Label

  ISDN interface                 CN1       Serial port              CN4

  Analog adapter                 CN2       AC power in              CN5

  Serial port                    CN3       Power switch             SW1

            Note: CN2 may not be present on all models.

                             DIAGNOSTIC LED(S)

     LED         Color         Status                Condition

     B2          Green           On           Data call connected on B2
                                                      channel

     B2          Yellow          On          Voice call connected on B2
                                                      channel

     B2          Green        Blinking      TA is dialing data call on B2
                                                      channel

     B2          Yellow       Blinking       TA is dialing voice call on
                                                     B2 channel

     B2           N/A            Off        B2 channel is not connected

     B1          Green           On           Data call connected on B1
                                                      channel

     B1          Yellow          On          Voice call connected on B1
                                                      channel

     B1          Green        Blinking      TA is dialing data call on B1
                                                      channel

     B1          Yellow       Blinking       TA is dialing voice call on
                                                     B1 channel

     B1           N/A            Off        B1 channel is not connected

                         DIAGNOSTIC LED(S) (CON'T)

     LED         Color          Status                Condition

      D          Yellow           On          Signal is not synchronized
                                               or ISDN is not connected

      D          Yellow        Blinking       Signal is synchronized but
                                                D-channel protocols not
                                                     established

      D          Yellow          Off            Signal is synchronized

    TEST         Yellow           On             TA failed last test

    TEST         Yellow        Blinking          TA is executing test

    TEST         Yellow          Off           TA is not executing test

    POWER        Yellow           On                 Power is on

    POWER        Yellow          Off                 Power is off

                 SUPPORTED STANDARD COMMANDS

                      Basic AT Commands

  +++, A/

  A, D, E, H, O, V, Z

  &D, &F, &W

                     Extended AT Commands

  \Q, \T

                         S-Registers

  S0

            Note: See MHI help file for complete information.

                         Proprietary AT Command Set

                                 CALL TYPE

  Type:                   Register

  Format:                 AT [cmds] S61=n [cmds]

  Description:            Selects the type of call the ISDN will make.
                          This register has no function on these models.

        Command                              Function

         S61=0            TA will dial according to dial modifiers.

         S61=2            TA will place ISDN call.

                             CALLER ID - DATA

  Type:          Register (read-only)

  Format:        AT [cmds] S66? [cmds]

  Description:   Displays the Caller ID information for data calls.

                             CALLER ID - VOICE

  Type:          Register (read-only)

  Format:        AT [cmds] S65? [cmds]

  Description:   Displays the Caller ID information for voice calls.

                                DCD SIGNAL

  Type:          Configuration

  Format:        AT [cmds] &Cn [cmds]

  Description:   Controls the behaviour of the DCD signal.

    Command                              Function

      &C0        DCD forced high.

      &C1        DCD forced high after carrier signal is detected.

      &C2        DCD forced high except at disconnect.

                         DISPLAY FIRMWARE REViSION

  Type:          Immediate

  Format:        AT [cmds] %V [cmds]

  Description:   Displays the TA's firmware revision.

                            DISPLAY INFORMATION

  Type:                  Immediate

  Format:                AT [cmds] In [cmds]

  Description:           Displays information requested about the TA.

        Command                              Function

          I0             Displays product identification code.

          I1             Displays ROM checksum.

          I4             Displays numeric product identification code,
                         precomputed checksum value, firmware revision,
                         model name, interface type, country code, and
                         data pump model.

                         DISPLAY MODIFIED COMMANDS

  Type:           Immediate

  Format:         AT [cmds] \S [cmds]

  Description:    Displays the settings of all commands that have been
                  modified.

                             DISPLAY REGISTERS

  Type:          Immediate

  Format:        AT [cmds] %R [cmds]

  Description:   Displays the settings of all status registers.

                       DYNAMIC BANDWIDTH ALLOCATION

  Type:                  Register

  Format:                AT [cmds] S70=n [cmds]

  Description:           Selects whether dynamic bandwidth allocation
                         will be used to allow simultaneous data and
                         voice calls.

        Command                              Function

         S70=0           Dynamic bandwidth allocation disabled.

         S70=1           Dynamic bandwidth allocation enabled.

                          ENDPOINT DISCRIMINATOR

  Type:                  Register

  Format:                AT [cmds] S83=nnnn [cmds]

  Description:           Sets the endpoint discriminator address for
                         multipoint PPP systems. Up to twenty numbers may
                         be specified.

                       ENDPOINT DISCRIMINATOR CLASS

  Type:            Configuration

  Format:          AT [cmds] S82=n [cmds]

  Description:     Sets the endpoint discriminator class for multipoint
                   PPP systems.

     Command                              Function

      S82=1        User-defined address.

      S82=2        IP address.

      S82=3        802.1 MAC address.

      S82=4        PPP magic number block.

      S82=5        Public Switched Network Directory number.

                                LINE SPEED

  Type:           Register

  Format:         AT [cmds] S60=n [cmds]

  Description:    Selects the line speed that the TA will attempt to
                  connect at.

     Command                             Function

     S60=56       TA will attempt to connect at 56Kbps.

     S60=64       TA will attempt to connect at 64Kbps.

                          LOCAL SERIAL PORT SPEED

  Type:          Configuration

  Format:        AT [cmds] $Bn [cmds]

  Description:   Sets the speed that the TA will communicate with the
                 DTE.

    Command                              Function

      $B0        Auto-detects current serial port speed.

     $B1200      Sets the serial port to 1200bps.

     $B2400      Sets the serial port to 2400bps.

     $B4800      Sets the serial port to 4800bps.

     $B9600      Sets the serial port to 9600bps.

    $B19200      Sets the serial port to 19.2Kbps.

    $B38400      Sets the serial port to 38.4Kbps.

    $B57600      Sets the serial port to 57.6Kbps.

    $B115200     Sets the serial port to 115.2Kbps.

                               MULTILINK PPP

  Type:          Register

  Format:        AT [cmds] S80=n [cmds]

  Description:   Selects whether the TA will use Multilink PPP.

    Command                              Function

     S80=0       Multilink PPP disabled.

     S80=1       Multilink PPP enabled.

                    MULTILINK PPP - SECOND PHONE NUMBER

  Type:                   Register

  Format:                 AT [cmds] S81=<#> [cmds]

  Description:            Sets the second phone number to be dialed when
                          attempting to connect with multilink PPP. If
                          this register is left blank then the number
                          given with the D command will also be dialed
                          for the second number.

                              PHONE NUMBER 1

  Type:          Register

  Format:        AT [cmds] S51=<#> [cmds]

  Description:   Sets the TAs first phone number.

                              PHONE NUMBER 2

  Type:          Register

  Format:        AT [cmds] S53=<#> [cmds]

  Description:   Sets the TAs second phone number.

                           PROTOCOL - B-CHANNEL

  Type:          Register

  Format:        AT [cmds] S71=n [cmds]

  Description:   Selects the protocol the TA will use on the B channels.

    Command                              Function

     S71=0       Auto-select common protocol.

     S71=1       TA will use PPP conversion.

     S71=2       TA will use V.120.

                               RESULT CODES

  Type:          Configuration

  Format:        AT [cmds] Qn [cmds]

  Description:   Enables modem to send result codes to the DTE.

    Command                              Function

       Q0        Result code sending enabled.

       Q1        Result code sending disabled.

       Q2        Result code sending enabled on originate mode only.

                       SERVICE PROFILE IDENTIFIER 1

  Type:          Register

  Format:        AT [cmds] S52=<#> [cmds]

  Description:   Sets the TAs first SPID.

                       SERVICE PROFILE IDENTIFIER 2

  Type:          Register

  Format:        AT [cmds] S54=<#> [cmds]

  Description:   Sets the TAs second SPID.

                                SWITCH TYPE

  Type:          Register

  Format:        AT [cmds] S50=n [cmds]

  Description:   Selects the type of IDSN switch the TA is connected to.

    Command                              Function

       1         AT&T 5ESS custom switch type.

       3         NI-1/AT&T 5ESS switch type.

       6         NI-1/National Telecom NI-1 or Siemens EWSD switch type.

                      TERMINAL ENDPOINT IDENTIFIER 1

  Type:                  Register (read-only)

  Format:                AT [cmds] S55? [cmds]

  Description:           Displays the first TEI assigned by the ISDN
                         switch. A value of 255 indicated that the switch
                         did not assign a TEI.

                   TERMINAL ENDPOINT IDENTIFIER 1 STATUS

  Type:          Register (read-only)

  Format:        AT [cmds] S57? [cmds]

  Description:   Returns a value indicating the status of the first TEI.

     Value                               Meaning

       0         TA has not attempted to initialize with SPID 1.

       1         TA succeeded in initializing with SPID 1.

       2         TA failed in initializing with SPID 1.

                      TERMINAL ENDPOINT IDENTIFIER 2

  Type:                  Register (read-only)

  Format:                AT [cmds] S56? [cmds]

  Description:           Displays the second TEI assigned by the ISDN
                         switch. A value of 255 indicated that the switch
                         did not assign a TEI.

                   TERMINAL ENDPOINT IDENTIFIER 2 STATUS

  Type:          Register (read-only)

  Format:        AT [cmds] S58? [cmds]

  Description:   Returns a value indicating the status of the second TEI.

     Value                               Meaning

       0         TA has not attempted to initialize with SPID 2.

       1         TA succeeded in initializing with SPID 2.

       2         TA failed in initializing with SPID 2.

                            U INTERFACE STATUS

  Type:          Register (read-only)

  Format:        AT [cmds] S59? [cmds]

  Description:   Returns a value indicating the status of the U
                 interface.

    Command                              Function

       0         U interface is not synchronized.

       1         U interface is synchronized.

                             V.120 FRAME TYPE

  Type:            Register

  Format:          AT [cmds] S73=n [cmds]

  Description:     Selects the frame type that the TA will use when in
                   V.120 mode.

     Command                             Function

      S73=0        TA will use I frames.

      S73=1        TA will use UI frames.

                         V.120 MAXIMUM FRAME SIZE

  Type:          Register

  Format:        AT [cmds] S74=n [cmds]

  Default:       256

  Range:         240 - 256

  Unit:          1 byte

  Description:   Selects the maximum frame size used for V.120 mode.

  Note:          Adtran ISDN uses a maximum frame size of 253 bytes.

