Simple loop: count down:

	program blastoff;
	var
		i: integer;
	begin
	i := 10;
	while i >= 0 do
		begin
		writeln(i);
		i := i - 1;
		end;
	writeln('We have ignition!');
	end.

Sample output

>10
>9
>8
>7
>6
>5
>4
>3
>2
>1
>0
>We have ignition!