3COM CORPORATION
================

   US ROBOTICS 1200

   Modem Type               Data (synchronous/asynchronous)       
   Maximum Data Rate        1200bps                               
   Data Bus                 External                              
   Data Modulation Protocol Bell 103A/212A                        

<gopher://bitreich.org/I/th99/t/0-9/54131-1.png>
   

   +------------------------------------------------------------+
   |                        CONNECTIONS                         |
   |------------------------------------------------------------|
   |      Purpose       | Location |     Purpose     | Location |
   |--------------------+----------+-----------------+----------|
   | Line out           |   CN1    | Power           |   CN4    |
   |--------------------+----------+-----------------+----------|
   | Line in            |   CN2    | Volume          |   SW3    |
   |--------------------+----------+-----------------+----------|
   | RS-232/422         |   CN3    | Power           |   SW2    |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                     DIAGNOSTIC LED(S)                      |
   |------------------------------------------------------------|
   | LED  | Color |  Status  |            Condition             |
   |------+-------+----------+----------------------------------|
   | LED1 |  Red  |    On    |  Analog loopback self test mode  |
   |------+-------+----------+----------------------------------|
   | LED1 | Green |    On    |            Data mode             |
   |------+-------+----------+----------------------------------|
   | LED2 |  Red  | Blinking | Modem is transmitting/receiving  |
   |      |       |          |               data               |
   |------+-------+----------+----------------------------------|
   | LED2 | Green |    On    |     Carrier signal detected      |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                         DTR SIGNAL                         |
   |------------------------------------------------------------|
   | Setting                    |             SW1/1             |
   |----------------------------+-------------------------------|
   |>> On                       |        DTR forced high        |
   |----------------------------+-------------------------------|
   | Off                        |          DTR normal           |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                        RESULT CODES                        |
   |------------------------------------------------------------|
   | Setting                        |           SW1/2           |
   |--------------------------------+---------------------------|
   |>> Verbose result codes enabled |            On             |
   |--------------------------------+---------------------------|
   | Numeric result codes enabled   |            Off            |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                    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 doe not answer on first ring |         On          |
   |--------------------------------------+---------------------|
   | Modem answers on first ring          |         Off         |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                       CARRIER DETECT                       |
   |------------------------------------------------------------|
   | Setting                       |           SW1/6            |
   |-------------------------------+----------------------------|
   |>> CD normal                   |            Off             |
   |-------------------------------+----------------------------|
   | CD forced high                |             On             |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                   MULT-LINE INSTALLATION                   |
   |------------------------------------------------------------|
   | Setting                       |           SW1/7            |
   |-------------------------------+----------------------------|
   |>> Single phone connected      |            Off             |
   |-------------------------------+----------------------------|
   | Multiple phones connected     |             On             |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                       AT COMMAND SET                       |
   |------------------------------------------------------------|
   | Setting                       |           SW1/8            |
   |-------------------------------+----------------------------|
   |>> AT command set recognized   |             On             |
   |-------------------------------+----------------------------|
   | AT command set disabled       |            Off             |
   +------------------------------------------------------------+

                     Proprietary AT Command Set

   +------------------------------------------------------------+
   |                 ANALOG LOOPBACK SELF TEST                  |
   |------------------------------------------------------------|
   | Type:        | Register                                    |
   |--------------+---------------------------------------------|
   | Format:      | AT [cmds] S16=n [cmds]                      |
   |--------------+---------------------------------------------|
   | Example:     | ATS16=139<CR>                               |
   |--------------+---------------------------------------------|
   | Description: | Selects the tone dialing test               |
   |--------------+---------------------------------------------|
   | Command      |                  Function                   |
   |--------------+---------------------------------------------|
   |      0       | Data mode.                                  |
   |--------------+---------------------------------------------|
   |      1       | Analog loopback.                            |
   +------------------------------------------------------------+