|An instance of
this function block type encapsulates a text field which can be used
to display the character string representation of a variable of any elementary
or derived IEC 61131-3 type, i.e., any subtype of the
generic type ANY.
- The data type name of the variable to be displayed is
specified by the TYPE input.
- An initial value to be displayed is spcified by the IVAL
- The displayed string is updated to the representation of the
IN input upon an occurrence of an event at the REQ
- The maximum number of characters displayable without
overflowing the text field is specified by the W (width)