Digital input.

 Configures a digital input signal in the Plant
 Configuration.

 The internal filter function, where FilterType
 specifies selected filter, concerns local Di signals,
 i.e. remote Di-signals are not affected by the internal
 filter function.
 The filter function means e.g. that the designer
 without any extra configuration and direct in the
 object may specify if:

 - the sampled signal have to be set for a certain time
 to be valid
 - a minimum of time have to elapse from that the
 sampled signal latest become FALSE until it is
 allowed to be TRUE again.

        Hints

 Put the object below a $PlantHier object in the
 development environment in such a way that it belongs
 to the same target node as its associated channel
 object.

 Optional text, for example the name of the signal or
 what it represents.

 Name of the associated channel object.

 Index in the DIValue array at the DiArea objects
 that are used for base frequency and partial frequency
 samples. Initiated at boot time by rt_ini.

 Pointer to ActualValue. The value is updated
 continuously. ConversionOn and InvertOn in the channel
 object ChanDi, see page 3-66, specifies if the value
 shall be converted before storage.

 InitialValue specifies starting value of the signal at
 so called 'cold start'. Which value that is used as
 starting value at warm restart ( = change of PLC
 program ) depends on whether the signal is new or not.
 If the signal has exist in the last program its last
 value will be used as starting value, otherwise InitialValue

 Not used.

 Xtt method configuration.
 Specification of the available methods for the object.
 If Flags.IsConfigured is set, the methods can be specified in
 the development environment. Otherwise they will be calculated
 in runtime.

 A XttGraph object that will open a graph that contains data for
 this object. This graph can be opened from the popup menu for
 this object.

 A DsTrend or PlotGroup object that contains a trend for this object.
 The trend can be opened from the popup menu for this object.

 A help topic in the xtt help file that contains help for this hierarchy.
 The help can be displayed from the popup menu for this object.

 A URL to the data sheet for the equipment in this hierarchy.
 The data sheet can be displayed from the popup menu for this object.

 A URL to the circuit diagram for the equipment in this hierarchy.
 The circuit diagram can be displayed from the popup menu for this object.

 If the attribute is empty, the CircuitDiagram method will look at the
 closest ancestor that has supplied a value in CircuitDiagram and use this
 URL instead. If this behavior is unwanted, put the string 'Disabled' in the
 attribute. This will disable the CircuitDiagram method for this object, and
 for any child with empty CircuitDiagram attribute.

 A photograph of the plant.
 A URL to a photo of the equipment.
 The photo can be displayed from the popup menu for this object.

 A note of the current status of the object.
 Notes are used to exchange information between operators. It is handled
 by the Note method.

 The internal filter function concerns only local
 Di-signals.

 Specifies the selected filter. The possible types of
 filters are:

 0 -- No filtering.
 1 -- Set and reset delay.

 Define filter constants in selected filter function,
 see FilterType. The constants are in seconds.

 If FilterType = 1, specifies FilterAttribute[0] the set
 delay and FilterAttribute[1] the rest delay.