----------------------------------------------------------------------------------
-- Company:
-- Engineer: Nenad Misic
--
-- Create Date:    21:59:15 12/04/2018
-- Design Name:
-- Module Name:    zadatak3 - Behavioral
-- Project Name:
-- Target Devices:
-- Tool versions:
-- Description:
--
-- Dependencies:
--
-- Revision:
-- Revision 0.01 - File Created
-- Additional Comments:
--
----------------------------------------------------------------------------------
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;

-- Uncomment the following library declaration if using
-- arithmetic functions with Signed or Unsigned values
--use IEEE.NUMERIC_STD.ALL;

-- Uncomment the following library declaration if instantiating
-- any Xilinx primitives in this code.
--library UNISIM;
--use UNISIM.VComponents.all;

entity zadatak3 is
    Port ( iCLK : in  STD_LOGIC;
           inRST : in  STD_LOGIC;
           inGO : in  STD_LOGIC;
           inSTOP : in  STD_LOGIC;
           oSEC : out  STD_LOGIC_VECTOR (7 downto 0));
end zadatak3;

architecture Behavioral of zadatak3 is
	signal sCNT : STD_LOGIC_VECTOR(24 downto 0);
	signal sTC : STD_LOGIC;
	signal sRES : STD_LOGIC_VECTOR(7 downto 0);
	signal sONOFF : STD_LOGIC;
begin

	process(iCLK) begin
		if(iCLK'event and iCLK='1') then
			if(inRST = '0') then
				sCNT <= "0000000000000000000000000";
				sTC <= '0';

			else
				if(sONOFF = '0') then
					sCNT <= sCNT + 1;
					if(sCNT = "1011011100011011000000000") then
						sTC <= not(sTC);
						sCNT <= "0000000000000000000000000";
					else
						sTC <= sTC;
					end if;
				end if;
			end if;
		end if;
	end process;


	process(sTC) begin
		if(inRST = '0') then
			sRES <= "00111100";
		else
			if(sONOFF = '0') then
				sRES <= sRES(0) & sRES(7 downto 1);
			else
				sRES <= sRES;
			end if;

		end if;
	end process;

	process(iCLK) begin
		if(iCLK'event and iCLK='1') then
			if(inRST = '0') then
				sONOFF <= '1';
			else
				if(inGO = '0') then
					sONOFF <= '0';
				end if;

				if(inSTOP = '0') then
					sONOFF <= '1';
				end if;
			end if;
		end if;
	end process;
	oSEC <= sRES;

end Behavioral;