[fpc-pascal]Week Day

[Rich Pasco]

No assembler is required; it's easily done in Pascal:

function Weekday(D,M,Y: word): word;
  (* Input D=day (1..31), M=month(1..12), Y=year(e.g. 2001) *)
  (* Returns 0=Sunday, 1=Monday, ... 6=Saturday *)
  const
    FD: array[1..12] of byte = (6,2,2,5,0,3,5,1,4,6,2,4);
  var
    Y1: integer;
  begin
    if M > 2 then Y1 := Y else Y1 := Y-1;
    WeekDay := ((D+(Y1 div 4)-(Y1 div 100)+(Y1 div 400)+Y+FD[M]) mod 7);
  end;

I hope this helps.

     - Rich