-- Shawn Nematbakhsh
-- UNIX DES Password Cracker 
-- LCD output entity

library IEEE;
use IEEE.STD_LOGIC_1164.all;
use IEEE.STD_LOGIC_ARITH.all;

entity LCD is
	port( 
		clk: in std_logic;
		rst: in std_logic;
   	    ASCII: in std_logic_vector(63 downto 0);		   
		ACK: in std_logic;
		rdy: in std_logic;
		D: out std_logic;
		REC: out std_logic);
		
		
		
end LCD;

--}} End of automatically maintained section

architecture arch of LCD is		

type STATE_TYPE is (WAITING,foo,waitz,OUTPUT,WAIT_FOR_LOW_ACK,FINISHED);
signal exe_state: STATE_TYPE;
signal data_shift : std_logic_vector(63 downto 0);
signal j: UNSIGNED(3 downto 0);

constant C0_56    : std_logic_vector (63 downto 0) := "0000000000000000000000000000000000000000000000000000000000000000";


signal v: UNSIGNED(6 downto 0);

begin					   
	
	process(clk,rst)
	begin
		if(rst='1') then

				D <= '0';
				v <= conv_unsigned(0,7);
				REC <= '0';
				data_shift <= "0000000000000000000000000000000000000000000000000000000000000000";

				exe_state <= WAITING;


					


		elsif(clk='1' and clk'event) then
	

			
			case exe_state is
				when WAITING =>	
				data_shift <= ASCII;
				if(rdy = '1') then
						exe_state <= OUTPUT;
					else
						exe_state <= WAITING;
					end if;

				
					 
				when foo =>
	

				D <=data_shift(63);
				j <= "0000";
				exe_state <= waitz;
				
				when waitz =>
					
				j <= j + '1';
				if(j = conv_unsigned(15,4)) then
					exe_state <= output;
				else
					exe_state <= waitz;
				end if;

				when output =>
				
				REC<='1';
					if(ACK='0')	then
						exe_state <= output;
					
					elsif(v = conv_unsigned(64,7)) then
						exe_state <= FINISHED;
					else			
						REC <= '0';
						
						
						v<= v + '1';		  
						data_shift <= data_shift(62 downto 0) & '0';
						exe_state <= WAIT_FOR_LOW_ACK;
					end if;

					
				when WAIT_FOR_LOW_ACK =>
			
				if(ACK = '0') then
						exe_state <= foo;
					else
						exe_state <= WAIT_FOR_LOW_ACK;
					end if;


				when FINISHED =>
	
					exe_state <= FINISHED;				
				
			end case;
		end if;

	end process;
			
	
end arch;