Defining alternative FDM overlays

An overlay definition contains an alternative softkey and screen setup that can be called from the main definition by a load_overlay statement.

The syntax of an overlay definition is:

overlay overlay_ref
{
      statement 1;
      ...
      statement n;
}

where:

overlay_ref
The name of the overlay. This must be an ASCII value that is unique within the file. It can have a maximum of 20 characters.
statement 1 ... statement n
A list of FDM script definition statements that define the setup to be used on the ADSI telephone. These statements can use any of the substitution parameters that are included in the main statement definition that contains this overlay, subject to the conditions described in Defining FDM main overlays.

For more information, see overlay.

The following is an example of an FDM overlay statement:

overlay Fred
{
      install_softkey fred;
      clear display;
      display "$message";
}

In this example, the softkey definition named fred is installed on a softkey, the display is cleared, and the value of the parameter called message is shown on the first line of the display. The parameter message must be passed to the ADSI state table. The parameter name must be included in the main definition that includes this overlay definition.