library IEEE;
use IEEE.STD_LOGIC_1164.ALL;

entity motorstart is
port (clock, a, b: in  std_logic;
        reset : in std_logic;
      u0, ut : out std_logic);
end motorstart;

architecture beh of motorstart is
signal pre_state : std_logic_vector(2 downto 0) := "000";
signal next_state: std_logic_vector(2 downto 0);

begin

process(pre_state)
begin

case pre_state is
when "000" => next_state <= "001";
when "001" => next_state <= "010";
when "010" => next_state <= "011";
when "011" => next_state <= "100";

when others => next_state <= "000";

end case;
end process;

process(a, b, pre_state, reset)
begin
    if pre_state = "000" and a = '1' and b = '0' then
      pre_state <= next_state;
    elsif pre_state /= "000" and pre_state /= "100" and b = '1' and a = '0' then
      pre_state <= next_state;
    elsif a = '0' and b = '0' then
        -- om både a och b är 0 har ingen knapptryking skett.
    else
        pre_state <= "100";
        u0 <= '1';

    end if;

    if reset = '1' then
      pre_state <= "000";
      ut <= '0';
      u0 <= '0';
    end if;

    if pre_state = "011" then
        ut <= '1';
    end if;
end process;

--process(pre_state)
--begin
--if pre_state = "011" then
--  ut <= '1';
--end if;
--end process;
end beh;