I want to read an Unsigned value and display it as a decimal number

Float values should be displayed as decimal values, however it is possible to show an UNSIGNED variable as a decimal in the DD.

For example: read the value 1800 display as 18.0: 

VARIABLE my_variable

{

  LABEL "Input";

  CLASS DEVICE & DYNAMIC;

  HANDLING READ;

  TYPE UNSIGNED_INTEGER (2)

  {

    DISPLAY_FORMAT ".1f";

    SCALING_FACTOR 0.01;

  }

}

TOK 8.1.32 will issue a warning for this (WARNING 622: Invalid Conversion Character 'f'in display format string for variable).