uses crt,dos;
type
 datetimetype=string[8];
  var
    reg:registers;
    h,m,s,w,time:datetimetype;
    i:integer;
  begin
  clrscr;
 repeat
   reg.ax:=$2c00;
   intr($21,reg);
   str(hi(reg.cx):2,h);
   str(lo(reg.cx):2,m);
   str(hi(reg.dx):2,s);
   w:=h+':'+m+':'+s;
   for i:=1 to length(w) do
     if w[i]=' ' then w[i]:='0';
  gotoxy(30,10); write(w);
  delay(500);
  clrscr;
 until keypressed;
  readkey;
end.