1  startloop

   Causes a Physical layer to place the line in loopback mode
  
   startloop [node node-id] modem connect line line-name -
             mode mode-type


   The Mode argument is required.  It specifies the type of loopback 
   used on the line.  The possible mode-types are:

   connector        Data is looped through a loopback connector
                    attached to the communications device.

   device           Data is looped in the communications device.

   driver           Data is looped in the driver of the
                    communications device.

   external         Data is looped through a null modem or a modem in
                    loopback mode.

   local            The communications device switches its local
                    modem into loopback mode by asserting the local
                    loopback signal. Data is then looped through that
                    modem.

   remote           The communications device switches the remote
                    modem into loopback mode by asserting the remote
                    loopback signal. Data is then looped through that
                    modem.

2  Exception_Messages

o  already in loopback

   The modem connect line entity specified in the command is already
   in loopback mode. Check that you specified the correct entity.
   Reissue the command with the correct name.


o  line not connected

   You have specified the value remote for the mode argument, yet the
   line is not connected. Connect the line (using the dial command)
   and the reissue the startloop command.


o  line disabled

   The line entity must be enabled before loopback.


o  constraint violation

   A startloop mode constraint has been violated.