-- Copyright (c) 2015 CERN
-- Maciej Suminski <maciej.suminski@cern.ch>
--
-- This source code is free software; you can redistribute it
-- and/or modify it in source code form under the terms of the GNU
-- General Public License as published by the Free Software
-- Foundation; either version 2 of the License, or (at your option)
-- any later version.
--
-- This program is distributed in the hope that it will be useful,
-- but WITHOUT ANY WARRANTY; without even the implied warranty of
-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-- GNU General Public License for more details.
--
-- You should have received a copy of the GNU General Public License
-- along with this program; if not, write to the Free Software
-- Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA


-- Test while loops in VHDL.

library IEEE;
use IEEE.std_logic_1164.all;
use IEEE.numeric_std.all;

entity vhdl_while is
    port(
        start: in std_logic;
        output: out integer
    );
end vhdl_while;

architecture test of vhdl_while is
begin
    process(start)
      variable a : integer := 0;
    begin
        if(rising_edge(start)) then
            while (a < 10) loop
                a := a + 1;
            end loop;
            output <= a;
        end if;
    end process;
end test;