         APPENDIX H.  TECHNICAL SPECIFICATIONS

      

USROBOTICS HIGH SPEED TECHNOLOGY (HST)

      16.8K, 14.4K, 12K, 9600, 7200 bps,
      synchronous/asynchronous, asymmetrical,
      450 bps back channel with automatic
      handshake adjustment to 300 bps, Trellis
      Coded Modulation (TCM), Quadrature
      Amplitude Modulation (QAM)

      4800 bps, synchronous/asynchronous,
      asymmetrical, 450 bps back channel with
      automatic handshake adjustment to 300
      bps, Quadrature Amplitude Modulation
      (QAM)


CCITT V.32 BIS

      14.4K. 12K, 9600, 7200 bps,
      synchronous/asynchronous, Trellis Coded
      Modulation (TCM)

      4800 bps, synchronous/asynchronous,
      Quadrature Amplitude Modulation (QAM)

ADDITIONAL COMPATIBILITY FEATURES

      CCITT V.25 2100 Hz tone

      CCITT V.23, 1200 bps, asymmetrical
      (1200/75 bps), Frequency Shift Keying
      (FSK)

      CCITT V.22 bis, 2400 bps,
      synchronous/asynchronous, Quadrature
      Amplitude Modulation (QAM)
      CCITT V.22, 1200 bps,
      synchronous/asynchronous, Differential
      Phase Shift Keying (DPSK)

      Bell 212A, 1200 bps,
      synchronous/asynchronous, Differential
      Phase Shift Keying (DPSK)

      Bell 103, 300/110 bps, asynchronous,
      Frequency Shift Keying (FSK)
      CCITT V.21, 300 bps, asynchronous,
      Frequency Shift Keying (FSK)

      300/110 bps, asynchronous, variable
      Frequency Shift Keying (FSK)

      USRobotics HST error control protocol,
      asymmetrical mode, at 16.8K, 14.4K, 12K,
      9600, 7200, 4800 bps, 450/300 bps back
      channel

      CCITT V.42 error control protocol at
      14.4K, 12K, 9600, 7200, 4800 bps (V.32
      bis mode) and at 2400/1200 bps

      CCITT V.42 bis data compression (all
      modes and speeds of 1200 bps and higher

      Microcom Networking Protocol (MNP) error
      control protocol, Levels 2-4 at 14.4K,
      12K, 9600, 7200, 4800 bps (V.32 bis
      mode) and at 2400/1200 bps

      Microcom Networking Protocol (MNP) Level
      5 data compression (all modes and speeds
      of 1200 bps and higher)

      DB-25 RS-232 terminal/modem interface

      Superset of industry standard AT command
      set, S-registers, DIP switches

      Optional MI/MIC closure

      Optional pulsed DSR


DTE (SERIAL PORT) RATES

      57.6K, 38.4K, 19.2K, 9600, 4800, 2400,
      1200, 300, 110 bps

LINK RATES

      16.8K (HST only), 14.4K, 12K, 9600,
      7200, 4800, 2400, 1200, 300, 110 bps
ADAPTIVE SPEED LEVELING

      16.8K (HST only), 14.4K, 12K, 9600,
      7200, 4800 bps


PHONE LINE INTERFACE

      RJ11, RJ45S phone jacks


COMMUNICATIONS CHANNEL

      Full/half duplex on 2-wire dial-up,
      dedicated, or leased phone lines;
      demand-driven high speed channel
      turnaround in HST mode; symmetrical
      speeds in V.32 bis mode


OPERATIONAL MODES

      Synchronous/Asynchronous, Auto
      Dial/Answer, Manual Originate/Answer,
      Smart/Dumb mode


DIALING

      Rotary (pulse 0-9), Touch-Tone (DTMF 0-
      9, #, *), a-z when in Quote (") Mode


DATA FORMAT

      Binary, serial; defaults to 7-bit word
      length, even parity

     Start Data             Stop
      Bits Bits   Parity    Bits
      
       1    7   Even, Odd    1
               Mark, Space
       1    7None, Even, Odd,2
               Mark, Space    
       1    8      None     1, 2

FRONT PANEL STATUS LIGHTS

       HS  High Speed (above 2400 bps)
       AA  Auto Answer/Answer
       CD  Carrier Detect
       OH  Off Hook
       RD  Received Data
       SD  Send Data
       TR  Terminal Ready (DTR)
       MR  Modem Ready/Test Mode
       RS  Request to Send
       CS  Clear to Send
       SYN Synchronous Mode
       ARQ Error control connection
           established
         

FLOW CONTROL BUFFERS

      Transmit Buffer

          Error control:  3.25k bytes

          Non-Error control:  1.5k bytes, 128-
      byte option

      Receive Buffer:  2K bytes


COMMAND BUFFER

      40 characters, exclusive of AT prefix,
      Carriage Return and spaces


TEST OPTIONS

      Analog loopback with test pattern
      Remote digital loopback
      Digital loopback
      Test pattern
      Dial test
CALL PROGRESS CODES

      NO DIAL TONE
      BUSY
      NO ANSWER
      RINGING
      VOICE


FAILED CALL TIMEOUT

      60-sec. default, programmable 2-255 sec.


ANSWER TONE TIMEOUT

      60 sec.


ANSWER TONE DETECTOR

      2200-2300 Hz


LOSS OF CARRIER (DISCONNECT TIMER)

      0.7-sec. default, programmable 0.2-25.5
      sec.


EQUALIZATION

      Adaptive


TRANSMITTER CARRIER FREQUENCIES

      USR-HST, 450 bps back channel
   Originate Mode:375 Hz
      Answer Mode:1800 Hz

      USR-HST, 300 bps back channel
   Originate Mode:350 Hz
      Answer Mode:1800 Hz

      V.32 bis
   Originate Mode:1800 Hz
      Answer Mode:1800 Hz

      V.23
      Originate Mode:   
             Mark:390 Hz
            Space:450 Hz
      Answer Mode:
             Mark:1300 Hz
            Space:2100 Hz
                  
      V.22 bis, V.22, Bell 212A
      Originate Mode:1200 Hz
      Answer Mode:2400 Hz
      
      Bell 103
      Originate Mode:   
             Mark:1270 Hz
            Space:1070 Hz
      Answer Mode:
             Mark:2225 Hz
            Space:2025 Hz
      
      V.21
      Originate Mode:
             Mark:980 Hz
            Space:1180 Hz
       Answer Mode:     
             Mark:1650 Hz
            Space:1850 Hz


RECEIVER CARRIER FREQUENCIES

      USR-HST, 450 bps back channel
   Originate Mode:1800 Hz
      Answer Mode:375 Hz

      USR-HST, 300 bps back channel
   Originate Mode:1800 Hz
      Answer Mode:350 Hz

      V.32 bis
   Originate Mode:1800 Hz
      Answer Mode:1800 Hz

      V.23
      Originate Mode:   
             Mark:1300 Hz
            Space:2100 Hz
      Answer Mode:
             Mark:390 Hz
            Space:450 Hz
      
      V.22 bis, V.22, Bell 212A
   Originate Mode:2400 Hz
      Answer Mode:1200 Hz

      Bell 103
   Originate Mode:      
             Mark:2225 Hz
            Space:2025 Hz
      Answer Mode:
             Mark:1270 Hz
            Space:1070 Hz

      V.21
   Originate Mode:
             Mark:1650 Hz
            Space:1850 Hz
      Answer Mode:
             Mark:980 Hz
            Space:1180 Hz


RECEIVE SENSITIVITY

      - 44 dBm + 2 dBm


TRANSMIT LEVEL

      - 9 dBm maximum


TRANSMITTER FREQUENCY TOLERANCE

      .01%
CERTIFICATION

      FCC Part 68 and Part 15, Class B
      Domestic; DOC (Canada), UL listed


POWER CONSUMPTION

      5 watts


SIZE

      8.30 x 12.65 x 1.57 inches
