Set16()

         Puts a value into an array16 position

    Syntax:

         Set16 ( aArray, nPos, xValue ) -> Nil

         aArray : The previously created array16
         nPos   : The array position to modify
         xValue : The new value of the specified position

    Description:

         Puts a value to an element of an array16. The value of nPos has
         to be equal or lower to the array16 number of elements.

    Return:

         Nothing.

    Example:

         a16 := New16 ( 15000, 0 )
         Set16 ( a16, 100, "Hello" )  // Now the element 100 is "hello"