SPORTSTER 14,400
                                APPENDIX B.  SUMMARIES AND TABLES
                                                                 
      
FRONT PANEL INDICATORS

           Table B.1_LED Indicators
                       
SymbolMeaning    Status
 AA Auto Answer/ Answer mode only:  ON if DIP
                 switch 5 is UP (OFF) when
                 Answer    the modem is
                 powered on, or register S0 is
                 set to 1 (Auto Answer mode),
                 and when answering a call;
                 OFF when the modem originates
                 a call.
 CDCarrier DetectON if DIP switch 6 is UP
                 (factory setting) and the
                 modem receives a valid data
                 signal (carrier) from a
                 remote modem, indicating that
                 data transmission is
                 possible.  Always ON if the
                 CD override is ON (DIP switch
                 6 DOWN).
 OH   Off Hook   ON when the modem takes
                 control of the phone line to
                 establish a data link.
 RDReceived Data Flashes when the modem sends
                 result codes or passes
                 received data bits to the
                 computer or terminal.
 SD  Send Data   Flashes when the computer or
                 terminal sends a data bit to
                 the modem.
 TRData Terminal ON if DIP switch 1 is UP
                 (factory setting) and the
                 modem
       Ready     receives a DTR signal from
                 the computer or terminal.  Al
                 ways ON if the DTR override
                 is on, DIP switch 1 DOWN.
 RS Request to   ON if your computer or
                 terminal sends the RTS signal
        Send     (your computer or terminal
                 and software must support
                 RTS).  OFF if the modem is
                 set to &R2 (Received Data
                 hardware flow control) and
                 the computer or terminal
                 lowers RTS.
 CSClear to Send ON until the modem lowers CTS
                 when Transmit Data hardware
                 flow control is enabled (&H1,
                 &H3).
ARQ/Error Control/    Data Mode:  Automatic
                 Repeat Request.  ON when the
FAX Fax Operations    modem is set to &M4 or
                 &M5 and successfully connects
                 with another modem under
                 error control.  Flashes
                 randomly when the modem
                 retransmits data to the
                 remote modem.
                 Fax Mode:  Flashes steadily
                 to indicate fax mode.

THE RS-232 INTERFACE

Description

      The RS-232 interface is a standard
      developed by the Electronic Industries
      Association (EIA).  It defines the
      signals and voltages used when data is
      exchanged between a computer or terminal
      and a modem or serial printer.
      The entire standard covers many more
      functions than are used in most data
      communications applications.  Data is
      transmitted between the devices over an
      RS-232 cable with a 25-pin male (DB-25P)
      connector to the modem and a 25-pin, 9-
      pin, 8-pin or custom-built connector to
      the computer or terminal.
      
Pin Assignments

      Pin assignments are factory-set in the
      Sportster 14,400 to match the standard
      DB-25 assignments in the following
      table.  DB-9 connectors for IBM PC/AT-
      compatible computers should be wired at
      the computer end of the cable as shown
      in the DB-9 column.  If you're using an
      Apple computer, ask your dealer for the
      correct modem cable for your Apple
      model.
      
      Table B.2_RS-232 Interface Pin Definitions
                       
                                Signal Source
      DB-25     DB-9 Circuit       Function
Terminal*_ Modem
      1    _   AA   Chassis Ground  Both
       2    3   BA   Transmitted DataTerminal
       3    2   BB   Received Data  Modem
       4    7   CA   Request to SendTerminal
       5    8   CB   Clear to Send  Modem
       6    6   CC   Data Set Ready Modem
       7    5   AB   Signal Ground   Both
       8    1   CF   Carrier Detect Modem
       12   _  SCF   Speed Indicate Modem
       20   4   CD   Data Terminal Ready
Terminal
       22   9   CE   Ring Indicate  Modem

      * Indicates terminal or computer.
Minimum Requirements

      Some computer/terminal equipment
      supports only a few of the RS-232 signal
      functions set in the Sportster 14,400.
      The minimum required for the modem to
      operate is as follows.
             Table B.3_Minimum Required Pins
                       
          DB-25    DB-9
           Pin     Pin      Function
           2       3       Transmitted
           Data
            3       2       Received Data
            7       5       Signal Ground
            20      4       Data Terminal
Ready*
           * Required only if you have
           the Data Terminal Ready
           Override switch OFF (DIP
           switch 1 UP).
           
Additional Flow Control Functions

      If your computer and software support
      Clear to Send and you wish to use
      Transmit Data hardware flow control
      (&H1), Pin 5 (DB-25) or Pin 8 (DB-9) is
      required.
      If your computer and software support
      Request to Send and you wish to use
      Received Data hardware flow control
      (&R2), Pin 4 (DB-25) or Pin 7 (DB-9) is
      required.
      
For 57.6K and 38.4K bps Serial Port Rate

      Your software and terminal or computer
      must support the 57.6K or 38.4K bps
      rate.  Make sure the RS-232 cable is
      shielded.  Cables are normally six feet
      long, but longer lengths are possible.
      If you encounter problems with signal
      degradation, try a shorter cable.
      If you decide to build your own cable,
      use a low-capacitance cable.  To further
      minimize the capacitance, connect only
      those functions (pins) that your
      application requires.
DIP SWITCH SUMMARY

Purpose

      The DIP switches, located at the rear of
      the modem, are for adapting the modem to
      your equipment and personal require
      ments.  The quick configuration guide
      that came with the modem indicates the
      recommended switch settings for many
      communications software packages.  If
      your software isn't included, you may
      need to review your software
      documentation to set DIP switches 1 and
      6 correctly for your program's
      requirements.
      Some users are able to move a single
      switch with a finger tip.  If this
      doesn't work for you, use a toothpick or
      other small instrument.
      
Operations

      The DIP switch settings are power-on and
      reset defaults, read by the Sportster
      14,400 when the computer is turned on or
      when you reset the modem.  If changed
      when the modem is on, switches 2-5
      require the ATZ (software reset) command
      to initiate the new settings.  The
      remaining (hardware) switches are
      automatically operative when set UP or
      DOWN.
            Table B.4_DIP Switches
                       
      Factory
SwitchSetting   Function
  1      UP     Data Terminal Ready (DTR)
                     Operations
                UP   Normal DTR operations:
                     computer or terminal must
                     provide DTR signal for
                     modem to accept commands;
                     dropping DTR terminates a
                     call
                DOWN Modem ignores DTR
                     (Override)
  2      UP     Verbal/Numeric Result Codes
                UP   Verbal (word) results
                DOWN Numeric results
  3     DOWN    Result Code Display
                UP   Results suppressed
                DOWN Results enabled
  4      UP     Command Mode Local Echo
                UP   Keyboard commands
                     displayed
                DOWN Echo suppressed
  5     DOWN    Auto Answer
                UP   Modem answers on first
                     ring
                DOWN Auto answer disabled
  6      UP     Carrier Detect (CD) Operations
                UP   Modem sends CD signal
                     when it connects with
                     another modem, drops CD
                     on disconnect
                DOWN CD always ON (Override)
  7      UP     Power-on and ATZ Reset
                     Software Defaults
                UP   Load from user-defined
                     nonvolatile memory
                     (NVRAM)
                DOWN Load factory settings
                     from read only memory
                     (ROM)
  8     DOWN    AT Command Set Recognition
                UP   Command recognition
                     disabled (Dumb Mode)
                DOWN Recognition enabled
                     (Smart mode)
DEFAULT SETTINGS

User-Programmable Defaults

      You can create your own default
      configuration and store it in
      nonvolatile random access memory (NVRAM)
      using the &W command described in
      Chapter 5.  As long as DIP switch 7 is
      UP when you power on or reset the modem,
      your defaults are loaded into the
      modem's random access memory (RAM).  To
      view your NVRAM settings, use the ATI5
      command.
      Tables on the next two pages list the
      options you can store in NVRAM,
      including S-Register settings.  If DIP
      switch 7 is DOWN at power-on, the
      factory settings listed in the tables
      are loaded instead.  The first time the
      modem is turned on, the NVRAM settings
      are the same as the factory settings.
      The following command example
      substitutes several user-defined
      defaults for factory settings.  The
      modem also stores the rate, word length
      and parity it detects from the command's
      AT prefix, which depend on how you first
      set those parameters in your software.
             AT X4 &B1 &M5 &H1 M3 &W <Enter>
        Table B.5_NVRAM Command Options
                       
NVRAM Options        Factory Setting
Handshake option       B0 CCITT answer
sequence
Normal/error control (ARQ) mode    &M4
Normal/ARQ
Data compression      &K1 Auto enable/disable
Transmit data flow control    &H0  Disabled

Rec'd data hardware flow control   &R1  Ignore
RTS
Rec'd data software flow control   &I0
Disabled
Serial port rate select&B0     Detect from AT
                          command; then follow
                          connection rate
Connection rate select&N0 Variable

Result code subset     X1 Extended
Error-control response codes  &A1  Enabled
Tone/Pulse dialing      P Pulse dial
Online local echo      F1 Disabled

Speaker control        M1 ON during dial
                          through connect
Remote Digital Loopback (RDL) &T5  Deny RDL
Data Set Ready override&S0    Enabled

Break handling        &Y1 Clear buffer, send
                          immediately
Stored telephone number&Zs    Blank
Pulse dial make/break ratio   &P0  U.S./Canada
Guard tone            &G0 U.S./Canada

Word length*              7
Parity*                   Even
Serial port rate*         19.2K bps


*  Detected by the modem from the AT prefix of
the &W command that writes your defaults to
NVRAM.  Set your software to the desired word
length, parity, and serial port rate defaults
before sending the modem the AT . . . &W
string.
      Table B.6_NVRAM S-Register Options
                                Factory
      NVRAM S-Register Options  Setting
      S2 Escape code character     43
      S3 Carriage Return character 13
      S4 Line Feed character       10
      S5 Backspace character        8
      S6 Dial wait-time, sec.       2
      S7 Carrier wait-time, sec.   60
      S8 Dial pause, sec.           2
      S9 Carrier Detect time, 1/10th
      sec.                          6
      S10Carrier loss wait-time, 1/10th
      sec.                          7
      S11Touch-Tone duration, spacing,
      msec.                        70
      S12Escape code guard time, 1/50th
      sec.                         50
      S13Bit-mapped functions       0
      S14Bit-mapped functions       0
      S15Bit-mapped functions       0
      S19Inactivity/hang up timer   0
      S21Break length, 1/100th msec.10
      S22XON character             17
      S23XOFF character            19
      S25DTR recognition time, 1/100th
      sec.                          5
      S27Bit-mapped functions       0
      S28V.21/V.23 fallback delay,
      1/10th msec.                  8
      S34Bit-mapped functions       6
      S38Disconnect wait time, sec. 0
     
     
      NOTE:  Bit-mapped registers have up
      to eight functions.  See instruc
      tions under S13 in the S-Register
      Summary in this appendix or the
      briefer summary in the Quick
      Reference Card.
S-REGISTER SUMMARY

Usage

      Users typically require the default
      values.  To change a setting, use the
      ATSr=n command, where r is the register
      and n is a decimal value from 0O255
      (unless otherwise indicated).
      The example below sets the modem's test
      timer to 10 seconds.
             ATS18=10 <Enter>
      The modem does not perform a value-range
      check.  Some values you select may not
      work with some equipment, and you'll
      have to readjust the settings.
      Use ATSr? to display the contents of a
      register, as follows.
             ATS20? <Enter>
             
             Table B.7_S-Registers
Register  Default   Function
   S0    See DIP    Sets the number of rings
                    on which to an-
         Switch 5   swer in Auto Answer Mode.
                    When DIP switch 5 is UP
                    the modem answers on the
                    first ring; S0=1 does the
                    same.  When DIP switch 5
                    is DOWN (factory setting),
                    Auto Answer is disabled;
                    S0=0 (modem answers on 0
                    rings, or never) does the
                    same.
   S1       0       Counts and stores the
                    number of rings from an
                    incoming call.
   S2       43      Stores the ASCII decimal
                    code for the escape code
                    character.  Default
                    character is I+U.  A value
                    of 128O255 disables the
                    escape code.
   S3       13      Stores the ASCII code for
                    the Carriage Return
                    character.  Valid range is
                    0O127.
   S4       10      Stores the ASCII decimal
                    code for the Line Feed
                    character.  Valid range is
                    0O127.
Register  Default   Function
   S5       8       Stores the ASCII decimal
                    code for the Backspace
                    character.  A value of
                    128O255 disables the
                    Backspace key's delete
                    function.
   S6       2       Sets the number of seconds
                    the modem waits before
                    dialing.  If set to X2 or
                    X4, the modem ignores this
                    register and dials as soon
                    as it detects a dial tone
                    (fast dials).
   S7       60      Sets the number of seconds
                    the modem waits for a
                    carrier.  May be set for
                    much longer duration if,
                    for example, the modem is
                    originating an
                    international connection.
   S8       2       Sets the duration, in
                    seconds, for the pause (,)
                    option in the Dial
                    command.
   S9       6       Sets the required
                    duration, in tenths of a
                    second, of the remote
                    modem's carrier signal
                    before recognition by the
                    Sportster.
  S10       7       Sets the duration, in
                    tenths of a second,  that
                    the modem waits after loss
                    of carrier  before hanging
                    up.  This guard time
                    allows the modem to
                    distinguish between a line
                    hit, or other disturbances
                    that momentarily break the
                    connection, from a true
                    disconnect (hang up) by
                    the remote modem.
                    While we don't recommend
                    connecting the modem to a
                    line with call waiting, if
                    you have it, you may wish
                    to adjust this setting up
                    ward to prevent the modem
                    from misinterpreting the
                    second call signal as a
                    disconnect by the remote
                    modem.  A better al
                    ternative is to ask your
                    phone company how to
                    temporarily disable call
                    waiting.
                    NOTE:  If you set S10=255,
                    the modem will not hang up
                    when carrier is lost.
                    Dropping DTR will force
                    the modem to hang up.
Register  Default   Function
  S11       70      Sets the duration and
                    spacing, in milliseconds,
                    of dialed Touch-Tones.
  S12       50      Sets the duration, in
                    fiftieths of a second, of
                    the guard time for the
                    escape code sequence
                    (+++).
  S13       0       Bit-mapped register.
                    Select the bit(s) you want
                    on and set S13 to the
                    total of the values in the
                    Value column.  For
                    example, ATS13=17 enables
                    bit 0 (value is 1) and bit
                    4 (value is 16).
                   BitValue   Result
                    0   1  Reset when DTR
                           drops
                    1   2  Reserved
                    2   4  Reserved
                    3   8  On DTR signal, Auto
                           Dial the number
                           stored in NVRAM
                    4   16 At power on/reset,
                           Auto Dial number
                           stored in NVRAM
                    5   32 Reserved
                    6   64 Disable MNP Level 3
                           (used for testing
                           Level 2)
                    7  128 Reserved
  S14       0       Bit-mapped.  Allowable non-
                    default value is 1.
                   BitValueResult
                    0   1  The modem hangs up
                           on receipt of +++,
                           returns to command
                           mode and sends the
                           NO CARRIER result
                           code; see Escape
                           Code Operations in
                           Chapter 6
                   1O7  _  Reserved
Register  Default   Function
  S15       0       Bit-mapped register.  To
                    set the register, see the
                    instructions for S13.
                   BitValueResult
                   0O2  _  Reserved
                    3   8  Reset non-ARQ mode
                           Transmit buffer
                           from 1.5K bytes to
                           128*
                    4   16 Disable MNP Level
                           4; retransmitting
                           the larger Level 4
                           data blocks may be
                           a problem if you
                           expect a great
                           number of errors
                           during a call
                   5O7  _  Reserved
      *The 1.5K-byte non-ARQ buffer allows
      data transfer with X- and Ymodem-type
      file transfer protocols without using
      flow control.
      The 128-byte option allows remote users
      with slower modems to stop data you're
      transmitting from scrolling off their
      screens.  When remote users send your
      computer an XOFF (Ctrl-S) and you stop
      transmitting, the data in transit from
      your modem's buffer doesn't exceed the
      size of their screen.
  S16       0       Bit-mapped test register.
                    Allowable value is 2.  For
                    information on the Dial
                    test (used in factory
                    testing), see Appendix F.
                   BitValueResult
                    0   _  Reserved
                    1   2  Dial test
                   2O7  _  Reserved
  S17       0       Reserved.
  S18       0       Test timer for &Tn
                    loopback testing.  Sets
                    the duration of testing,
                    in seconds, before the
                    modem automatically times
                    out and terminates the
                    test.  When S18 is set to
                    0, the timer is disabled.
                    See Appendix F for test
                    instructions.
Register  Default   Function
  S19       0       Sets the duration, in
                    minutes, for the Inac
                    tivity Timer.  The timer
                    activates when there is no
                    data activity on the phone
                    line; at timeout the modem
                    hangs up.  S19=0 disables
                    the timer.
  S20       0       Reserved.
  S21       10      Sets the length, in 10-
                    millisecond units, of
                    Breaks sent from the modem
                    to the computer or
                    terminal; applies to ARQ
                    mode only.
  S22       17      Stores the ASCII decimal
                    code for the XON
                    character.  Valid range is
                    0O127.
  S23       19      Stores the ASCII decimal
                    code for the XOFF
                    character.  Valid range is
                    0O127.
  S24       0       Reserved.
  S25       5       Sets the duration, in
                    hundredths of a second,
                    that DTR must be dropped
                    so that the modem doesn't
                    interpret a random glitch
                    as a DTR loss.  (Most
                    users will want to use the
                    default; this register is
                    useful for setting
                    compatibility with older
                    systems running under
                    older operating software.)
  S26       0       Reserved.
  S27       0       Bit-mapped register.  To
                    set the register, see the
                    instructions for S13.
                   BitValue   Result
                   0   1  Enable CCITT V.21
                           modulation at 300
                           bps for overseas
                           calls; in V.21
                           mode, the modem
                           answers both over
                           seas and domestic
                           (U.S. and Canada)
                           calls, but only
                           originates V.21
                           calls
               S27 continued on following page
Register  Default   Function
S27 (cont.)                Bit     Value
Result
                    1   2  Enable unencoded
                           (non-trellis-
                           coded) modulation
                           in V.32 mode;
                           rarely used part
                           of CCITT
                           Recommendation
                           V.32
                   2   4  Disable V.32
                           modulation
                   3   8  Disable 2100 Hz
                           answer tone to
                           allow two V.42
                           modems to connect
                           more quickly
                   4   16 See below
                   5   32 See below
                   6   64 Reserved
                   7  128 Unusual software
                           incompatibility.
                           Some software may
                           not accept 7200,
                           12,000 and 14,400
                           bps result codes.
                           This setting
                           disables the codes
                           and displays the
                           9600 code instead.
                    Error control handshaking
                    options:  select the total
                    values of bits 4 and 5.
                   Bit 4   Bit 5   Result
                    0   0   Complete
                            handshaking
                            sequence:  V.42
                            Detection, LAPM
                            error control,
                            MNP.
                    16  0   Disable MNP.
                    0   32  Disable V.42
                            Detection and
                            LAPM.
                    16  32  Combined value of
                            48 negotiates LAPM
                            without Detection
                            phase.  Choose
                            this value if the
                            remote modem uses
                            LAPM but does not
                            support the
                            Detection phase.
Register  Default   Function
  S28       8       Sets the duration, in
                    tenths of a second, of the
                    EIA-specified Multimode
                    Training.  Default = 8 (.8
                    seconds).  This gives V.32
                    bis modems additional time
                    to connect with most
                    U.S./Canada modems at 9600
                    bps or higher before
                    falling back to attempt a
                    V.23 connection (some U.K.
                    modems, 1200 bps) or a
                    V.21 connection (European
                    modems, 300 bps).
                    If calling/answering low-
                    speed, overseas modems
                    under V.21 or V.23
                    modulation, setting S28 to
                    zero eliminates the delay,
                    giving a faster connect
                    time.
  S29       20      Reserved for USRobotics'
                    internal use.
  S30       0       Reserved.
  S31       0       Reserved.
  S32       1       Reserved.
  S33       0       Reserved.
  S34       6       Bit mapped.  Allowable
                    values are S34=6, S34=7,
                    S34=14, and S34=15.
                   BitValueResult
                    0   1  Disable V.32 bis.
                           Used for
                           troubleshooting;
                           USRobotics'
                           Technical Support
                           may require that
                           you disable V.32
                           bis for testing
                           purposes.
                   1O2  _  Reserved
                    3   8  Enable V.23
                           modulation
                   4O7  _  Reserved
  S35       0       Reserved.
  S36       0       Reserved.
  S37       0       Reserved.
Register  Default   Function
  S38       0       Sets an optional delay, in
                    seconds, before a forced
                    hang-up and clearing of
                    the Transmit buffer when
                    DTR drops during an ARQ
                    call.  This allows time
                    for a remote modem to
                    acknowledge receipt of all
                    transmitted data before it
                    is disconnected.  Default
                    = 0:  the modem
                    immediately hangs up when
                    DTR drops.
                    This option only applies
                    to connections terminated
                    by dropping DTR.  If the
                    modem receives the ATH
                    command, it ignores S38
                    and immediately hangs up.
ASCII CHART

      The following chart may be useful for
      programming.

