Configuring a Device for a Modem

Use this procedure to configure a Digi 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.

Procedure

1. Connect a serial cable between the port and modem. 
2. Power the modem on.
3. At the command prompt enter:

   chown uucp:uucp /dev/ttyaa00

   where ttyaa00 is the name of the device.

4. Connect to the modem by entering this command at a command prompt

   cu -l /dev/ttyaa00 -s 38400

   where ttyaa00 is the name of the non modem control device for the port.

5. Set the modem to answer after the first ring with this command:

   ats0=1

6. Train the modem to the port speed with this command:

   at&w

7. Enter any other desired modem commands.
8. Terminate the connection to the modem with a tilde followed by a period:

   ~.

9. To manually configure the port to use hardware flow control by inserting this command in a Linux startup file:

   ditty-rp rtspace ctspace /device

   where /device is the name of the Digi device. Insert the command in a startup file so it remains in effect after a reboot.

   Alternately, use a gettydef entry that uses hardware flow control (see the next step)

10. Edit the /etc/inittab file and add a getty entry for the device. The getty name that configures your device can vary from system to system. The following example is only meant to serve as a guide.

    Example:

    An example of an mgetty modem script which is available both in RedHat and Debian is:

    T3:23:respawn: /sbin/mgetty -x0 -s 115200 ttyaa00

    where ttyaa00 is the name of the device.

11. Enable the port for login by rebooting the system or by entering this command at your Linux command prompt:

    init q