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

   PHONE LINK 300

   Card Type                Modem (asynchronous)                  
   Chip Set                 U.S. Robotics                         
   Maximum Data Rate        300bps                                
   Data Bus                 External                              
   Data Modulation Protocol WE 103/113                            

                                                            54167

   +------------------------------------------------------------+
   |                        CONNECTIONS                         |
   |------------------------------------------------------------|
   |       Function        | Label  |   Function    |   Label   |
   |------------------------------------------------------------|
   | Line out                  |   CN1    | DC power     | CN4  |
   |---------------------------+----------+--------------+------|
   | Line in                   |   CN2    | Power switch | SW1  |
   |---------------------------+----------+--------------+------|
   | RS-232/422                |   CN3    |              |      |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                 USER CONFIGURABLE SETTINGS                 |
   |------------------------------------------------------------|
   |                 Setting                 | Label | Position |
   |-----------------------------------------+-------+----------|
   | Originate enabled                       | SW2/A |   Off    |
   |-----------------------------------------+-------+----------|
   | Answer enabled                          | SW2/A |    On    |
   |-----------------------------------------+-------+----------|
   | Local echo disabled                     | SW2/B |   Off    |
   |-----------------------------------------+-------+----------|
   | Local echo enabled                      | SW2/B |    On    |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |                     DIAGNOSTIC LED(S)                      |
   |------------------------------------------------------------|
   | LED  | Color | Status |             Condition              |
   |------+-------+--------+------------------------------------|
   |  ON  |  Red  |   On   |            Power is on             |
   |------+-------+--------+------------------------------------|
   |  ON  |  Red  |  Off   |            Power is off            |
   |------+-------+--------+------------------------------------|
   |  CD  |  Red  |   On   |      Carrier signal detected       |
   |------+-------+--------+------------------------------------|
   |  CD  |  Red  |  Off   |    Carrier signal not detected     |
   |------+-------+--------+------------------------------------|
   |  TS  |  Red  |   On   |         Test mode enabled          |
   |------+-------+--------+------------------------------------|
   |  TS  |  Red  |  Off   |         Test mode disabled         |
   |------+-------+--------+------------------------------------|
   |  SD  |  Red  |   On   |     Modem is transmitting data     |
   |------+-------+--------+------------------------------------|
   |  SD  |  Red  |  Off   |   Modem is not transmitting data   |
   |------+-------+--------+------------------------------------|
   |  RD  |  Red  |   On   |      Modem is receiving data       |
   |------+-------+--------+------------------------------------|
   |  RD  |  Red  |  Off   |    Modem is not receiving data     |
   +------------------------------------------------------------+

   +------------------------------------------------------------+
   |               MISCELLANEOUS TECHNICAL NOTES                |
   |------------------------------------------------------------|
   |      Note: Transmit level adjustment, this can be made by  |
   |      looking under the Phone Link for a screw              |
   |      potentiometer. Turning the screw clockwise will       |
   |      increase transmit level and turning the screw         |
   |      counterclockwise will decrease transmit level. This   |
   |      should be done if you are experiencing errors         |
   |      receiving data or the remote receiving data from the  |
   |      Phone Link.                                           |
   |                                                            |
   |      Diagram not available.                                |