var i;

begin
  call cvclear;
  i:=1;
  while 1=1 do 
  begin
    while cvx<0 do
      call wait(10);
    while cvx]0 do
      begin
        call cvclear;
        call cvdraw(i,0,0,cvx,cvy);
        call wait(100)
      end;
    i:=i+1;
    if i>imagemax then
      i:=1
  end
end.