Displays or modifies the contents of the regular AX25 "ID"
beacons, which are transmitted every IDINTERVAL.
The "port" argument is either a valid port number, or zero.
In the latter case the command displays or sets the "global"
IDTEXT.
If "text" is not specified, the current IDTEXT for the
specified port is displayed.
If "text" is specified, the IDTEXT parameter for the specified
port is changed to the new value.
The minimum abbreviation of this command is IDT.