Logical Operators on Words

[JimKueneman]

Is this normal:

Code: Select all

const
  MASK = $0001;

type
  TMyRec = record
     Bob: Word
  end;

var
  MyRec: TMyRec;

begin
  MyRec.Bob := $FF01;
  MyRec.Bob := MyRec.Bob and not MASK 
end; 

What happens is the upper byte is also cleared.

To fix do this:

Code: Select all

const
  MASK = Word($0001);

For a compiler/MCU that is based on words this seems like the compiler should be able to see I am working with words and I should not have to remember to always force constants into words.

Jim

[zristic]

It defaults to byte, in order to generate smaller code. Yes, you have to explicitly specify word if you want word.