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-- Company: 
-- Engineer: 
-- 
-- Create Date:    15:23:48 04/02/2009 
-- Design Name: 
-- Module Name:    led_show - Behavioral 
-- Project Name: 
-- Target Devices: 
-- Tool versions: 
-- Description: 
--
-- Dependencies: 
--
-- Revision: 
-- Revision 0.01 - File Created
-- Additional Comments: 
--
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library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_ARITH.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;

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

entity led_show is
    Port ( iCLK : in  STD_LOGIC; -- clock procesora
           inRST : in  STD_LOGIC; -- dugme reset
           inRL : in  STD_LOGIC;	-- dugme rotate left
           inRR : in  STD_LOGIC;	-- dugme rotate right
           inSTOP : in  STD_LOGIC;	-- dugme stop
           inBL : in  STD_LOGIC;  -- dugme blink
           oLED : out  STD_LOGIC_VECTOR (7 downto 0)); -- izlazi ka diodama
end led_show;

architecture Behavioral of led_show is

--11999999
	constant cCLOCK_MAX: integer := 10 ; -- otkucaji clocka za pola sekunde 
	signal sTICK_COUNT: integer := 0;  -- brojac otkucaja clock-a
	signal sSTATE: integer := 0; 		-- stanja (test = 0 , stop = 1 , rl =2, rr = 3 , bl = 4)
	signal sSEK: integer :=0; --  brojac sekundi za test stanje
	signal sTEMP: std_logic_vector (7 downto 0):= "11111111"; -- za blinkanje dioda
	signal sLED: std_logic_vector (7 downto 0) := "11111111";
begin

	process(iCLK) begin
		if(iCLK'event and iCLK='1' ) then 
			if(sSTATE/=0) then sSEK<=0; end if;
			sTICK_COUNT<= sTICK_COUNT + 1;
			if(sTICK_COUNT= cCLOCK_MAX) then	
				sSEK<= sSEK+1;
				sTICK_COUNT<=0;
			end if;
			if(inRST='0' or sSTATE = 0) then
				sSTATE<=0;
				if(sSEK=3) then 
						sSTATE<=1; 
						sSEK<=0;
					end if;
				elsif(sSTATE = 1 and inRL = '0') then sSTATE<=2;
				elsif(sSTATE = 1 and inRR = '0') then sSTATE<=3;
				elsif(sSTATE = 1 and inBL = '0') then sSTATE<=4;
				elsif(inSTOP = '0') then sSTATE<=1; 
			end if;
			end if;
				--else 
				--	end if;
		--	end if;
	end process;
	
	process(iCLK) begin
	if(iCLK'event and iCLK='1') then			
   case (sSTATE) is 
		when 0 =>
						sLED<="11111111";
		
      when 1 =>
			sLED<="10000000";
		--	oLED<=sLED;
		when 2 =>
			if(sTICK_COUNT= 0) then
			  sLED<=sLED(6 downto 0) & sLED(7); 
			  end if;
      when 3 =>
			if(sTICK_COUNT= 0) then
			sLED<= sLED(0) & sLED(7 downto 1);
			end if;
      when 4 =>
			if(sTICK_COUNT= 0) then
				sLED<=sTEMP;
				sTEMP<=not sTEMP;
				--sLED <= sTEMP;
				end if;
		when others =>
				sLED<="11111111";
	--			oLED<=sLED;
		end case;	oLED<=sLED;
	end if;
	end process;
end Behavioral;