Debouncing - Testing

library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_misc.all;
use IEEE.NUMERIC_STD.ALL;

entity LedCounter is
    Port ( clk : in  STD_LOGIC;
           rst : in  STD_LOGIC;
              button : in STD_LOGIC;
           leds : out  STD_LOGIC_VECTOR (7 downto 0));
end LedCounter;

architecture Behavioral of LedCounter is

    -- Clocks since the button was last pressed
    signal csp : unsigned(31 downto 0) := (others => '0');
    -- Holds the value that will be assigned to the LEDs
    signal leds_counter : unsigned(6 downto 0) := (others => '0');
    -- Last sampled value of the button
    signal last_button_value : std_logic := '0';
    signal countdown : unsigned(31 downto 0) := (others => '0');

    signal ffs : std_logic_vector(1 downto 0);
    signal result : std_logic;
begin

    process(result)
    begin
        if(rising_edge(result)) then
            leds_counter <= leds_counter + 1;
        end if;
    end process;

    -- Always assign LEDs the value of leds_counter
    leds(6 downto 0) <= std_logic_vector(leds_counter);
    leds(7) <= '0';
--  process(clk, rst)
--      variable sr : std_logic_vector(3 downto 0) := (others => '0');
--      constant sr_chk : std_logic_vector(sr'high-1 downto 0) := (others => '1');
--  begin
--      if(rst = '1') then
--          leds_counter <= (others => '0');
--          sr := (others => '0');
--      elsif(rising_edge(clk)) then
--          sr(sr'high downto 1) := sr (sr'high-1 downto 0);
--          sr(0) := button;
--          --if(sr(sr'high downto 1) = sr_chk and sr(0) = '0') then
--          --if(sr(19 downto 0) = sr_chk and sr(20) = '0') then
--          if(sr(sr'high-1 downto 0) = sr_chk and sr(sr'high) = '0') then
--              leds_counter <= leds_counter + 1;
--          end if;
--      end if;
--  end process;

--  process(clk)
--      variable ffs : std_logic_vector(9 downto 0) := (others => '0');
--      variable co : unsigned(10 downto 0) := (others => '0');
--      variable a : std_logic;
--  begin
--      if(rising_edge(clk)) then
--          ffs(ffs'high downto 1) := ffs(ffs'high - 1 downto 0);
--          ffs(0) := button;
--          a := xor_reduce(ffs);
--          if(a = '1') then
--              co := (others => '0');
--          elsif(co(co'high) = '0') then
--              co := co + 1;
--          else
--              if(ffs(1) = '1') then
--                  leds_counter <= leds_counter + 1;
--              end if;
--              --result <= ffs(1);
--          end if;
--      end if;
--  end process;

--  process(clk, rst)
--      variable counter : unsigned(31 downto 0) := (others => '0');
--      variable flipflops : std_logic_vector(3 downto 0) := (others => '0');
--      constant max : unsigned(counter'range) := to_unsigned(100_000_000 / 100, counter'length);
--  begin
--      if(rst = '1') then
--          counter := (others => '0');
--          flipflops := (others => '0');
--      elsif(rising_edge(clk)) then
--          flipflops(flipflops'high downto 1) := flipflops(flipflops'high-1 downto 0);
--          flipflops(0) := button;
--
--          if(and_reduce(flipflops) = '1') then
--              counter := to_unsigned(100_000_000 / 100, counter'length);
--          elsif(counter > 0) then
--              counter := counter - 1;
--          else
--              if(button = '1') then
--                  leds_counter <= leds_counter + 1;
--              end if;
--          end if;
--      end if;
--  end process;

--  process(clk, rst)
--      constant max : unsigned(31 downto 0) := to_unsigned(100_000_000/10, 32);
--      variable counter : unsigned(31 downto 0) := max;
--      variable last_button_state : std_logic := '0';
--  begin
--      if(rst = '1') then
--          counter := max;
--          last_button_state := '0';
--      elsif(rising_edge(clk)) then
--          if(counter > 0) then
--              counter := counter - 1;
--          elsif(button = '1' and last_button_state = '0') then
--              counter := max;
--              leds_counter <= leds_counter + 1;
--          end if;
--
--          last_button_state := button;
--      end if;
--  end process;


    process(clk, rst)

        constant start : unsigned(31 downto 0) := to_unsigned(100_000_000 / 1000, 32);
        variable counter : unsigned(start'range) := (others => '0');
    begin
        if(rst = '1') then
            counter := (others => '0');
            ffs <= (others => '0');
        elsif(rising_edge(clk)) then
            ffs(1) <= ffs(0);
            ffs(0) <= button;

            if(ffs = "10" or ffs = "10") then
                counter := start;
            elsif(counter > 0) then
                counter := counter - 1;
            else
                result <= button;
            end if;
        end if;
    end process;

--  PROCESS(clk)
--  variable flipflops : std_logic_vector(1 downto 0) := (others => '0');
--  variable counter_out : unsigned(27 downto 0) := (others => '0');
--  --variable result : std_logic;
--  variable counter_set : std_logic;
--  BEGIN
--
--    IF(clk'EVENT and clk = '1') THEN
--      flipflops(0) := button;
--      flipflops(1) :=  flipflops(0);
--      counter_set := flipflops(0) xor flipflops(1);
--      If(counter_set = '1') THEN                  --reset counter because input is changing
--        counter_out :=  (OTHERS => '0');
--      ELSIF(counter_out(counter_out'high) = '0') THEN --stable input time is not yet met
--        counter_out :=  counter_out + 1;
--      ELSE                                        --stable input time is met
--        result <= flipflops(1);
--      END IF;
--    END IF;
--  END PROCESS;

--  process(clk, rst)
--      variable ffs : std_logic_vector(1 downto 0) := (others => '0');
--      variable counter_out : unsigned(19 downto 0) := (others => '0');
--  begin
--      if(rst = '1') then
--          counter_out := (others => '0');
--          ffs := (others => '0');
--      elsif(rising_edge(clk)) then
--          ffs(1) := ffs(0);
--          ffs(0) := button;
--          if(ffs(0) xor ffs(1) = '1') then
--              counter_out := (others => '0');
--          elsif(counter_out(counter_out'high) = '0') then
--              counter_out := counter_out + 1;
--          else
--              leds_counter <= leds_counter + 1;
--          end if;
--      end if;
--  end process;


--  process(clk, rst)
--      --variable countdown : unsigned(31 downto 0) := (others => '0');
--  begin
--      if(rst = '1') then
--          countdown <= (others => '0');
--          leds_counter <= (others => '0');
--      elsif(rising_edge(clk)) then
--          if(countdown /= 0) then
--              countdown <= countdown - 1;
--              leds(7) <= '0';
--          else
--              leds(7) <= '1';
--              if(button = '1' and last_button_value = '0') then
--                  countdown <= to_unsigned(100_000_000 / 100, countdown'length);
--                  leds_counter <= leds_counter + 1;
--              elsif(button = '0' and last_button_value = '1') then
--                  countdown <= to_unsigned(100_000_000 / 100, countdown'length);
--              end if;
--
--
--          end if;
--
--
--      end if;
--  end process;

--  process(clk, rst)
--  begin
--      -- clear things
--      if(rst = '1') then
--          leds_counter <= (others => '0');
--          csp <= (others => '0');
--          -- Assume the button has not been pressed
--          last_button_value <= '0';
--      elsif(rising_edge(clk)) then
--          -- Check to make sure some time has passed since the button was pressed
--          if(csp > 100_000_000 / 5) then
--              -- Check to see if the button is on the rising edge
--              if(button = '1' and last_button_value = '0') then
--                  -- Increment the counter and reset the counts since last pressed
--                  leds_counter <= leds_counter + 1;
--                  csp <= (others => '0');
--              end if;
--          else
--              -- The max count has not been reached.  Increment.
--              csp <= csp + 1;
--          end if;
--
--          -- Always update the last value signal with the current value
--          last_button_value <= button;
--      end if;
--  end process;



--  process(clk, rst)
--      variable c : unsigned(31 downto 0) := (others => '0');
--  begin
--      if(rst = '1') then
--          c := (others => '0');
--      elsif(rising_edge(clk)) then
--          if(c > 100_000_000 / 10 and button = '1' and last_button_value = '0') then
--              leds_counter <= leds_counter + 1;
--              c := (others => '0');
--          else
--              if(c <= 100_000_000 / 4) then
--                  c := c + 1;
--              end if;
--          end if;
--      end if;
--
--      last_button_value <= '0';
--  end process;

end Behavioral;