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-- Copyright (C) 2002 Morgan Kaufmann Publishers, Inc
-- This file is part of VESTs (Vhdl tESTs).
-- VESTs is free software; you can redistribute it and/or modify it
-- 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.
-- VESTs 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 VESTs; if not, write to the Free Software Foundation,
-- Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
entity counter is
port ( clk, reset : in bit; count : out natural );
end entity counter;
--------------------------------------------------
architecture behavior of counter is
begin
incrementer : process is
variable count_value : natural := 0;
begin
count <= count_value;
loop
loop
wait until clk = '1' or reset = '1';
exit when reset = '1';
count_value := (count_value + 1) mod 16;
count <= count_value;
end loop;
-- at this point, reset = '1'
count_value := 0;
count <= count_value;
wait until reset = '0';
end loop;
end process incrementer;
end architecture behavior;
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