
U.S. ROBOTICS, INC.

COURIER 2400E/PS

Card Type                Modem (Asynchronous)
Chip Set                 U.S. Robotics
Maximum Data Rate        2400bps
Data Bus                 Unidentified
Data Modulation Protocol Unidentified

                                                                      V1983

                         Proprietary AT Command Set

                                   ABORT

  Type:          Immediate

  Format:        Any key

  Description:   Aborts answering/originating a call; modem hangs up.

                                  ANSWER

  Type:              Immediate

  Format:            AT [cmds] A

  Description:       Enables answer mode, the modem goes off-hook;
                     pressing any key will abort.

                              ANSWER SEQUENCE

  Type:          Configuration

  Format:        AT [cmds] Bn [cmds]

  Description:   Selects the answer sequence the modem will use

    Command                              Function

       B0        ITU-T answer sequence enabled

       B1        Bell answer sequence enabled

                                 ATTENTION

  Type:              Immediate

  Format:            AT [cmds]

  Description:       Tells the modem that a command follows or use alone
                     to test OK result code

                          BIT-MAPPED REGISTER S13

  Format                 AT [cmds] S13=n [cmds]

  Default:               0

  Range:                 0-222

  Unit:                  Bit-mapped

  Description:           Controls auto-answer, result code pause, DTR
                         dialing, reset dialing, MNP3 and hardware reset.

    Bit       Value                         Function

     0              0    Not used

     1               0   Auto-answer mode disabled

                    1    Auto-answer mode on originate enabled

     2               0   Result code pause enabled

                    1    Result code pause disabled

     3               0   DTR dialing disabled

                    1    DTR dialing enabled

     4               0   Reset dialing disabled

                    1    Reset dialing enabled, dials number at position
                         0 in NVRAM.

     5              0    Not used

     6               0   MNP 3 enabled

                    1    MNP 3 disabled

     7               0   Hardware reset disabled

                    1    Hardware reset enabled

                          BIT-MAPPED REGISTER S15

  Format           AT [cmds] S15=n [cmds]

  Default:         0

  Range:           0-81

  Unit:            Bit-mapped

  Description:     Controls escape sequence, MNP4, and MNP compliance.

   Bit    Value                           Function

    0          0   Normal operation

              1    Hang up on receiving +++

  1 - 3     000    Not used

    4          0   MNP 4 enabled

              1    MNP 4 disabled

    5         0    Not used

    6          0   MNP normal

              1    MNP adjusted for non compliant modems

                                BREAK TYPE

  Type:          Configuration

  Format:        AT [cmds] &Yn [cmds]

  Description:   Configures action of break signal

    Command                              Function

      &Y0        Empty buffer only

      &Y1        Empties buffer and break is sent immediately

      &Y2        Do not empty buffer and break is sent immediately

      &Y3        Do not empty buffer or send break

                            CARRIER DETECT (CD)

  Type:          Configuration

  Format:        AT [cmds] &Cn [cmds]

  Description:   Controls the CD signal

    Command                              Function

      &C0        Modem does not respond to CD signal

      &C1        CD signal normal

                           CARRIER FAILURE CODES

  Type:             Register

  Format:           AT [cmds] S20=n [cmds]

  Description:      Reports codes which correspond to the possible causes
                    of NO CARRIER

      Value                                Meaning

        0           Ant key abort

        1           DTR dropped

        2           Escape sequence

        3           Loss of carrier

        4           Inactivity time-out

        5           ARQ connection not established, hang-up.

        6           ARQ retry time-out

        7           Receive link disconnect

                                COMPRESSION

  Type:          Configuration

  Format:        AT [cmds] &Kn [cmds]

  Description:   Selects data compression

    Command                              Function

      &K0        Data compression disabled

      &K1        Auto enabled/disable data compression

      &K2        Data compression enabled

                         CONNECTION FAILURE CODES

  Type:               Register

  Format:             AT [cmds] S17=n [cmds]

  Default:            0

  Description:        Reports codes which correspond to the possible
                      causes of a connection failure

                             CONNECTION SPEED

  Type:            Configuration

  Format:          AT [cmds] &Nn [cmds]

  Description:     Sets connection speed, modem will hang up if it cannot
                   connect.

     Command                             Function

       &N0         Normal link

       &N1         300bps

       &N2         1200bps

       &N3         2400bps

                         DATA TERMINAL READY (DTR)

  Type:          Configuration

  Format:        AT [cmds] &Dn [cmds]

  Description:   Selects modem response to DTR

    Command                              Function

      &D0        Modem does not respond to DTR

      &D1        Modem goes to command mode after DTR toggles

      &D2        Modem is initialized after DTR goes off

                                   DIAL

  Type:                 Immediate

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

  Example:              ATDT 443-3388,,,1111;

  Description:          Dials telephone number according to any modifiers
                        included in the string

  Note:                 Any combination of modifiers can be used to
                        produce the desired dial functions in sequence.

        Command                             Function

           P            Pulse dialing enabled

           T            Tone dialing enabled

           ,            Dialing paused for 2 seconds to a maximum amount
                        of time specified in S8 register

           ;            Modem returned to command state after dialing.
                        Can only be placed at the end of the dial
                        command.

           "            Dials letters that follow, ATDT"GOMICRO

           !            Flash function initiated

           W            Dialing resumed following dial tone detection

           @            Wait for quiet answer, then proceeds to execute
                        the rest of the dial string.

           R            Answer mode enabled; originate mode disabled
                        following handshake initiation.

                           DIAL - STORED NUMBER

  Type:          Immediate

  Format:        AT [cmds] DSn [cmds]

  Description:   Dial stored number from memory location n

                                   ECHO

  Type:            Configuration

  Format:          AT [cmds] En [cmds]

  Description:     Controls echo function; display keyboard commands when
                   enabled.

     Command                             Function

       E0          Echo function disabled

       E1          Echo function enabled

                              ECHO - ON-LINE

  Type:           Configuration

  Format:         AT [cmds] Fn [cmds]

  Description:    Selects whether commands sent while in data mode are
                  echoed

    Command                              Function

       F0         Local echo enabled

       F1         Local echo disabled

                        ERROR CORRECTION MODE (ARQ)

  Type:          Configuration

  Format:        AT [cmds] &Mn [cmds]

  Description:   Selects active error correction protocols

    Command                              Function

      &M0        Normal mode only enabled

      &M4        Normal/ARQ mode enabled

      &M5        ARQ mode only enabled

                              ESCAPE SEQUENCE

  Type:                   Immediate

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

  Description:            Initiates the escape sequence and returns the
                          modem to the on-line command state if it
                          receives three escape characters set in S2
                          within the time allotted by S12.

            Note: Do not precede this command with AT.

                           EXTENDED RESULT CODES

  Type:          Configuration

  Format:        AT [cmds] &An [cmds]

  Description:   Selects extended result codes

    Command                              Function

      &A0        ARQ result codes disabled

      &A1        ARQ result codes enabled

                          FACTORY DEFAULT PROFILE

  Type:          Configuration

  Format:        AT [cmds] &F [cmds]

  Description:   Load default profile in NVRAM

                         FLOW CONTROL PASSTHROUGH

  Type:          Configuration

  Format:        AT [cmds] &In [cmds]

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

    Command                              Function

      &I0        Flow control disabled

      &I1        XON/XOFF passthrough enabled

      &I2        XON/XOFF passthrough disabled

                             FLOW CONTROL TYPE

  Type:          Configuration

  Format:        AT [cmds] &Hn [cmds]

  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

                             FLOW CONTROL TYPE

  Type:           Configuration

  Format:         AT [cmds] &Rn [cmds]

  Description:    Controls receive data hardware flow control and RTS
                  signals

    Command                              Function

      &R1         Modem ignores RTS

      &R2         Received data to DTE when RTS is on

                                GUARD TONE

  Type:          Configuration

  Format:        AT [cmds] &Gn [cmds]

  Description:   Commands the modem to transmit a guard tone

            Note: Used primarily for international data transmission

    Command                              Function

      &G0        Guard tone disabled

      &G1        550Hz guard tone enabled

      &G2        1800Hz guard tone enabled

                               HOOK CONTROL

  Type:          Immediate

  Format:        AT [cmds] Hn [cmds]

  Description:   Selects whether the modem is on-hook or off-hook

    Command                              Function

       H0        Modem commanded to go on-hook (hang-up)

       H1        Modem commanded to go off-hook (pick-up)

                             INACTIVITY TIMER

  Type:                  Register

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

  Default:               0

  Range:                 0-90

  Unit:                  1 minute

  Description:           Sets the length of time that the modem does not
                         receive information before it disconnects; S19=0
                         will disable.

                                 JACK TYPE

  Type:          Configuration

  Format:        AT [cmds] &Jn [cmds]

  Description:   Selects jack type

    Command                             Jack Type

      &J0        RJ-11C

      &J1        RJ-12, RJ-13

                          LIST AMPERSAND COMMANDS

  Type:          Immediate

  Format:        AT [cmds] &$ [cmds]

  Description:   Displays ampersand (&) commands

                            LIST DIAL COMMANDS

  Type:          Immediate

  Format:        AT [cmds] D$ [cmds]

  Description:   Displays dial commands

                             LIST S-REGISTERS

  Type:          Immediate

  Format:        AT [cmds] S$ [cmds]

  Description:   Displays the S-registers

                                  ON-LINE

  Type:           Immediate

  Format:         AT [cmds] O [cmds]

  Description:    Return to on-line command (data transmission) mode

            Note: The O command must be placed at the end of the command
            string.

                               PULSE DIALING

  Type:              Configuration

  Format:            AT [cmds] P [cmds]

  Description:       Enables pulse dialing

            Note: This command can be duplicated with the P modifier in
            the D (Dial) command.

                            PULSE DIALING RATIO

  Type:          Configuration

  Format:        AT [cmds] &Pn [cmds]

  Description:   Selects pulse dial make/break ratio

    Command                              Function

      &P0        39/61ms at 10pps (North America)

      &P1        33/67ms at 10pps (Europe)

                           REPEAT COMMAND STRING

  Type:             Configuration

  Format:           AT [cmds] > [cmds]

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

                          REPEAT PREVIOUS COMMAND

  Type:           Immediate

  Format:         A/

  Description:    Repeats previous command, mainly used for redial

            Note: Do not precede this command with AT, or follow it with
            <CR>.

                            REPORT INFORMATION

  Type:          Immediate

  Format:        AT [cmds] In [cmds]

  Description:   Displays information requested

    Command                              Function

       I0        Reports product code

       I1        Reports ROM checksum

       I2        Reports RAM checksum

       I3        Reports call duration

       I4        Reports current command settings

       I5        Reports NVRAM settings

                               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

                            RESULT CODE FORMAT

  Type:             Configuration

  Format:           AT [cmds] Vn [cmds]

  Description:      Selects word or numeric format for information-text
                    and result codes

     Command                              Function

        V0          Numeric format enabled

        V1          Verbose (word) format enabled

                     SELECT CALL PROGRESS RESULT CODES

  Type:                  Configuration

  Format:                AT [cmds] Xn [cmds]

  Description:           Enables selection of tone detection and
                         associated result code format options

        Command                              Function

           X0            Busy and dial tone detection disabled; result
                         codes 0-4 enabled.

           X1            Busy and dial tone detection disabled; result
                         codes 0-5 and 10 enabled

           X2            Busy tone detection disabled, dial tone
                         detection enabled; result codes 0-6 and 10
                         enabled; also adaptive dialing, and fast dialing
                         enabled.

           X3            Busy tone detection enabled, dial tone detection
                         disabled; result codes 0-5, 7-10 enabled; also
                         adaptive dialing, wait for second dial tone, and
                         wait for answer enabled.

           X4            Busy and dial tone detection enabled; result
                         codes 0-10 enabled; also adaptive dialing, wait
                         for second dial tone, wait for answer, and fast
                         dialing enabled.

           X5            Busy tone detection enabled, dial tone detection
                         disabled; result codes 0-5, 7-12 enabled; also
                         adaptive dialing, wait for second dial tone, and
                         wait for answer enabled.

           X6            Busy and dial tone detection enabled; result
                         codes 0-10 enabled; also adaptive dialing, wait
                         for second dial tone, wait for answer, and fast
                         dialing enabled.

  Note: Valid numeric result codes; 0-8, and 10-12.

                             SERIAL PORT SPEED

  Type:                Configuration

  Format               AT [cmds] &Bn [cmds]

  Description:         Sets the maximum allowable data exchange rate from
                       the local computer and modem.

       Command                              Function

         &B0           Speed of last AT command

         &B1           300bps

         &B2           600bps

         &B3           1200bps

         &B4           2400bps

         &B5           4800bps

         &B6           9600bps

         &B7           19.2Kbps

                                SOFT RESET

  Type:          Immediate

  Format:        AT [cmds] Z [cmds]

  Description:   Resets modem to profiles saved in non-volatile RAM

                               SPEAKER MODE

  Type:                Configuration

  Format:              AT [cmds] Mn [cmds]

  Description:         Selects various speaker options

       Command                             Function

         M0            Speaker disabled

         M1            Speaker enabled until carrier signal detected

         M2            Speaker enabled

         M3            Speaker enabled following dialing, then disabled
                       after carrier signal detected.

                              SPEAKER VOLUME

  Type:          Configuration

  Format:        AT [cmds] Ln [cmds]

  Description:   Controls speaker volume

    Command                              Function

       L0        Low volume setting

       L1        Low volume setting

       L2        Medium volume setting

       L3        Highest volume setting

                              STATUS-REGISTER

  Type:          Configuration

  Format:        Read: AT [cmds] Sn? [cmds]

                 Write: AT [cmds] Sn=x [cmds]

  Description:   Writes to or reads from a specified register

                           STORE ACTIVE PROFILE

  Type:          Configuration

  Format:        AT [cmds] &W [cmds]

  Description:   Writes current values to non-volatile RAM templates

                          STORE TELEPHONE NUMBER

  Type:               Configuration

  Format:             AT [cmds] &Zn=(phone # & modifiers)

  Description:        Writes selected telephone numbers into the
                      non-volatile memory at location n

            Note: The characters described in the D command are valid for
            use in the &Z command.

       Command                             Function

        &Zn?          Displays phone number from non-volatile memory at
                      location n

                                TEST MODES

  Type:             Configuration

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

  Description:      Controls tests. Analog loopback, dial, and self tests
                    (test pattern).

      Command                             Function

       S16=0        Testing disabled

       S16=1        Local analog loopback enabled

       S16=2        Dial test enabled

       S16=4        Test pattern enabled

       S16=5        Local analog loopback and test pattern enabled

                               TONE DIALING

  Type:              Configuration

  Format:            AT [cmds] T [cmds]

  Description:       Enables tone dialing mode

            Note: This command can be duplicated with the T modifier in
            the D (Dial) command.

