Configuring a TTY Device for a Modem

Use this procedure to configure a RealPort device for a Dial-in/Dial-out modem connection. Configuring a device for a modem requires familiarity with both the operating system and the modem being used. While the following procedure is sufficient for most cases, it may be necessary to take additional steps to properly configure your modem or to set up the operating system for a specific application.

The Digi One RealPort or PortServer and RealPort should be properly installed, configured and functioning before proceeding. This procedure assumes that a tty has been created for the modem. See Creating and Configuring ttys.

Procedure

  1. Connect a proper cable between the port and modem. See the Digi One RealPort or PortServer Cable Guide.
  2. Set the port to dev=rp on the Digi One RealPort or PortServer by entering this command at a root prompt:

    set port dev=rp ra=12

    This example sets PortServer port 12 to be a RealPort device.

    Note: If your PortServer firmware does not support the dev=rp option, use dev=prn instead.

  3. If you are using 8-pin RJ-45 cabling from the Digi One RealPort or PortServer to the terminal, set the port to altpin=on by entering this command at a root prompt:

    set port altpin=on ra=12

    This example sets altpin=on for port 12 of a Digi One RealPort or PortServer.

  4. Turn the modem on.
  5. Access a root prompt on the AIX system.
  6. Add an entry for the device in the file /usr/lib/uucp/Devices. The following example allows a connection of 9600 baud to the device:

    Direct tty3 - 9600 direct

  7. Use the following command to connect to the modem:

    cu -ml ttyX

    In this command, ttyX is the device name for the port.

    Alternately, telnet can also be used to connect to the modem:

    telnet [ipaddress] 20XX

    In this command, [ipaddress] is the IP address of the Digi One RealPort and PortServer and XX is the number of the port to which the modem is connected.

    The modem should respond with an AT prompt.

  8. Train the modem to the port speed by entering this command at the AT prompt: 

at&w

  1. Terminate the connection by entering: 

    ~. (a tilde followed by a period)

and choosing Enter at the AT prompt.

  1. At an AIX root prompt, enter this command:

    smit tty

  2. Choose Change/Show Characteristics of a TTY.
  3. Choose a TTY device. This is an example of a listed device:

    tty7 Available 00-00-04-02 Asynchronous Terminal

    In this example, the first 00 is the bus number. This is unused and will always be 00. The second 00 is the slot number. This is unused and will always be 00. The number 04 is the sa device number. The number 02 is the port number.

  4. Set Enable LOGIN to share.
  5. Set BAUD rate to the modem's highest configurable baud rate.
  6. Set PARITY, BITS per character, and number of STOP BITS to match the settings of the modem.
  7. Set FLOW CONTROL to be used to match the flow control used by the modem.