3COM CORPORATION

US ROBOTICS 2400

Modem Type             Data (synchronous/asynchronous)
Maximum Data Rate      2400bps
Data Bus               External
Fax Class              Class I & II
Data Modulation        Bell 103A/212A
Protocol
                       ITU-T V.22bis

[Image]

                                CONNECTIONS

         Purpose             Location          Purpose           Location

  Line out                     CN1       Power in                  CN4

  Line in                      CN2       Volume                    R1

  RS-232/422                   CN3       Power switch              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

  » Off                             Extended result codes enabled

  On                               Extended result codes disabled

          RESULT CODES DISPLAY

  Setting                  SW1/3

  » On               Display disabled

  Off                 Display enabled

                 ECHO DISPLAY

  Setting                      SW1/4

  » Off                  Local echo enabled

  On                    Local echo disabled

                                AUTO ANSWER

  Setting                                            SW1/5

  » On                                Modem doe not answer on first ring

  Off                                     Modem answers on first ring

           CARRIER DETECT

  Setting               SW1/6

  » Off               CD normal

  On               CD forced high

               MULTIPLE PHONE INSTALLATION

  Setting                               SW1/7

  » Off                         Single phone connected

  On                          Multiple phones connected

                      AT COMMAND SET

  Setting                               SW1/8

  » On                        AT command set recognized

  Off                          AT command set disabled

                         Proprietary AT Command Set

                               TIME DISPLAY

  Type:          Immediate

  Format:        AT [cmds] Kn [cmds]

  Example:       AT K1 *L2 #E1<CR>

  Description:   Displays the current call time or clock time.

    Command                              Function

       K0        Display length of last call.

       K1        Display actual time.

                               HELP SCREENS

  Type:                Immediate

  Format:              AT <prefix>$

  Example:             AT &$<CR>

  Description:         Shows command help screens for all commands
                       beginning with the given prefix, or no prefix if
                       none is given.

       Command                              Function

          $            Shows ATx help screen.

         D$            Shows ATDx help screen.

         S$            Shows S-register help screen.

                           REPEAT COMMAND STRING

  Type:          Configuration

  Format:        AT [cmds] >

  Example:       AT DT1(303) 443-3388 > <CR>

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

                         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.

       2         Dial testing.

       4         Test pattern.

       5         Analog loopback and test pattern.