--********************************************* 
-- 
LIBRARY IEEE; 
USE IEEE.STD_LOGIC_1164.ALL; 
USE IEEE.STD_LOGIC_ARITH.ALL ; 
USE IEEE.STD_LOGIC_UNSIGNED.ALL ; 
LIBRARY altera; 
USE altera.maxplus2.ALL; 
--********************************************* 
ENTITY elec_lock IS 
  PORT (   
    CLK_4M   : IN   STD_LOGIC ;         
       CLK_SCAN : OUT  STD_LOGIC_VECTOR (3 downto 0) ; --scan sequence 
    KEY_IN   : IN   STD_LOGIC_VECTOR (2 downto 0) ; --KEY IN button code 
    FLAG_NUMB : OUT STD_LOGIC ; 
    FLAG_FUNC : OUT STD_LOGIC ; 
    LED_COM :  OUT STD_LOGIC ;                      -- for LP-2900 only 
    CLEAR : OUT STD_LOGIC ;                         --**  
    ENLOCK : OUT  STD_LOGIC ;                       --1:LOCK, 0:UNLOCK 
    NUMB_CNT : OUT STD_LOGIC_VECTOR (2 DOWNTO 0) ; 
    BCD_CODE :  OUT STD_LOGIC_VECTOR (15 DOWNTO 0) ; 
    SELOUT : OUT STD_LOGIC_VECTOR (1 DOWNTO 0) ;    --FIT TO LP-2900 
    SEGOUT   : OUT  STD_LOGIC_VECTOR(6 DOWNTO 0) -- SEG7 Display  
    ); 
END elec_lock ; 
--********************************************* 
ARCHITECTURE a OF elec_lock IS 
  component debouncing 
    port(  d_in   : IN STD_LOGIC ; 
         clk    : IN STD_LOGIC ;   
         d_out  : OUT STD_LOGIC ) ; 
  end component ; 
  SIGNAL CLK : STD_LOGIC ;  
  SIGNAL CLK_KEYBOARD : STD_LOGIC_VECTOR(1 downto 0) ;  
  SIGNAL CLK_DEBOUNCE : STD_LOGIC ;   
  SIGNAL CLK_DISPLAY  : STD_LOGIC_VECTOR(1 downto 0) ;  
  SIGNAL C          : STD_LOGIC_VECTOR(2 downto 0) ; 
  SIGNAL N          : STD_LOGIC_VECTOR(3 downto 0) ; 
  SIGNAL F          : STD_LOGIC_VECTOR(3 downto 0) ; 
  SIGNAL FN         : STD_LOGIC ; 
  SIGNAL FF         : STD_LOGIC ; 
  SIGNAL SEL        : STD_LOGIC_VECTOR (3 downto 0) ;  
  SIGNAL OUT_NUMB :  STD_LOGIC_VECTOR(3 downto 0) ; 
  SIGNAL OUT_FUNC :   STD_LOGIC_VECTOR(3 downto 0) ; 
    SIGNAL ACC : STD_LOGIC_VECTOR (15 DOWNTO 0) ; 
    SIGNAL REG : STD_LOGIC_VECTOR (15 DOWNTO 0) ; 
  SIGNAL RR2 : STD_LOGIC ;                        -- ** RR2 = Clear 
  SIGNAL QA, QB, BB : STD_LOGIC ; 
  SIGNAL NC : STD_LOGIC_VECTOR (2 DOWNTO 0) ; 
  SIGNAL   DB     : STD_LOGIC_VECTOR( 3 DOWNTO 0);-- Number TO Display  
  SIGNAL  SEG    : STD_LOGIC_VECTOR( 6 DOWNTO 0);-- SEG7 Display Signal 
BEGIN 
--******************************************* 
-- CONNECTION  
   OUT_NUMB <= N ; 
  OUT_FUNC <= F ; 
  FLAG_NUMB <= FN  ; 
  FLAG_FUNC <= FF  ; 
  CLK_DEBOUNCE <= CLK ; 
  NUMB_CNT<= NC ; 
  SEGOUT(6 DOWNTO 0) <= SEG;  -- Seven Segment Display  
  SELOUT <= CLK_DISPLAY ; 
  LED_COM <= '1' ;            --For LP-2900 only  
--********************************************* 
-- scan signal generator  
counter : block 
  Signal  Q   : STD_LOGIC_VECTOR(22 DOWNTO 0);             
   Signal   S   : STD_LOGIC_VECTOR(1 DOWNTO 0) ;  --keyboard scan about 15H
  SIGNAL   SEL : STD_LOGIC_VECTOR (3 downto 0);   
BEGIN 
 
  PROCESS (Clk_4M)               
  Begin 
    IF CLK_4M'Event AND CLK_4M = '1' then 
      Q <= Q+1; 
    END IF; 
  END PROCESS; 
      CLK <= Q(0) ;  --CLK = CLK_DEBOUNCE 
      CLK_KEYBOARD <= Q(5 DOWNTO 4) ;     -- ***00-01-10-11 
      CLK_DISPLAY  <= Q(5 DOWNTO 4) ; 
-- To generate keyboard scan sequence  1110->1101->1011->0111      
      SEL <=   "1110" WHEN CLK_KEYBOARD=0 ELSE 
      "1101" WHEN CLK_KEYBOARD=1 ELSE 
      "1011" WHEN CLK_KEYBOARD=2 ELSE 
      "0111" ;  
  CLK_SCAN <= SEL ; 
end block counter ; 
--********************************************* 
--debounuing ckt 
debounuing : block 
begin 
  U1: debouncing PORT MAP ( 
      d_in => key_in(0) , 
      d_out => C(0) , 
      clk => CLK 
     ); 
  U2: debouncing PORT MAP ( 
      d_in => key_in(1) , 
      d_out => C(1)  , 
      clk => CLK 
       ); 
  U3: debouncing PORT MAP ( 
      d_in => key_in(2) , 
      d_out => C(2)  , 
             clk => CLK  
     ); 
END block debounuing  ; 
--****************************************************** 
--key_decoder 
key_decoder : block  
  signal Z : std_logic_VECTOR(4 downto 0) ;   --KEY POSITION 
  SIGNAL R1, R0 : STD_LOGIC ; 
 
begin 
  PROCESS(clk) 
  begin 
    Z <= CLK_KEYBOARD & C ; 
    IF CLK'EVENT  AND CLK = '1'  THEN 
      case Z is 
      when "11101" => N <= "0000" ;--0 
      when "00011" => N <= "0001" ;--1 
      when "00101" => N <= "0010" ;--2 
      when "00110" => N <= "0011" ;--3 
      when "01011" => N <= "0100" ;--4 
      when "01101" => N <= "0101" ;--5 
      when "01110" => N <= "0110" ;--6 
      when "10011" => N <= "0111" ;--7 
      when "10101" => N <= "1000" ;--8 
      when "10110" => N <= "1001" ;--9 
      when others   => N <= "1111" ; 
      end case ; 
    END IF ; 
--**************************** 
    IF CLK'EVENT  AND CLK = '1'  THEN 
      case  Z is 
      when "11011" => F <= "0100" ;--*_LOCK 
      when "11110" => F <= "0001" ;--#_UNLOCK 
      when others  => F <= "1000" ; 
       end case ;    
    END IF ; 
  end process ; 
  FN <=  NOT ( N(3) AND N(2) AND N(1) AND N(0) ) ; 
  FF <=  ( NOT F(3) AND F(2) AND NOT F(1) AND NOT F(0)) OR (NOT F(3) AND NOT F(2)AND NOT F(1) AND F(0) ) ; 
--To generate clear signal for ACC  
PROCESS (CLK) 
BEGIN 
IF CLK'EVENT  AND CLK = '1'  THEN 
R1 <= R0 ; R0 <= FF ;  
END IF ; 
RR2 <= R1 AND NOT R0 ; 
CLEAR <= RR2 ; 
END PROCESS ; 
end block key_decoder ; 
--***************************************************** 
--KEYIN /// BACK /// ALL CLEAR 
KEYIN_PROCESS :BLOCK 
  SIGNAL RST,D0,D1: STD_LOGIC ;   
BEGIN  
  PROCESS(CLK,FN,RST) 
  BEGIN 
    IF RST = '1' THEN  
      ACC <= "0000000000000000" ;  --CLEAR INPUT 
      NC <= "000" ; 
    ELSE  
      IF  FN'EVENT AND FN = '1'  THEN  
     IF NC < 4 THEN 
      ACC <= ACC(11 DOWNTO 0) & N ; 
      BB <= '0' ;  
      NC <= NC + 1 ; 
                ELSE       
      BB <= '1' ; 
     END IF ; 
      END IF ; 
    END IF ; 
  END PROCESS ; 
    RST  <=  RR2 ; 
END BLOCK KEYIN_PROCESS ; 
--********************************************* 
LOCK_PROCESS : BLOCK 
BEGIN 
  PROCESS(CLK,F) 
  BEGIN 
    IF (CLK'EVENT AND CLK = '1') THEN 
     IF NC = 4  THEN 
      IF F(2) = '1' THEN  --LOCK  
       REG <= ACC ;  
       QA <= '1' ; QB <= '0'; 
      ELSIF F(0) = '1' THEN     --UNLOCK 
       IF  REG = ACC THEN    --CHECK PIN CODE 
        QB <= '1' ; QA<= '0'; 
       END IF ; 
      ELSIF  ACC = "0010010110000000" THEN    
                    --To set "2580" is the Universal. pin number 
        QB <= '1' ; QA<= '0'; 
      END IF ; 
          END IF; 
      END IF ; 
  END PROCESS ; 
END BLOCK LOCK_PROCESS ; 
 
  ENLOCK <= QA AND NOT QB ; 
  BCD_CODE <= ACC ; 
--********************************************** 
MULTIPLEXER : BLOCK 
BEGIN 
  DB <= ACC(15 DOWNTO 12) WHEN CLK_DISPLAY = 0 ELSE    
        ACC(11 DOWNTO  8) WHEN CLK_DISPLAY = 1 ELSE 
        ACC(7  DOWNTO  4) WHEN CLK_DISPLAY = 2 ELSE 
        ACC(3  DOWNTO  0) WHEN CLK_DISPLAY = 3 ELSE 
      "1111" ; 
 
End Block MULTIPLEXER ; 
--********************************************** 
SEVEN_SEGMENT : Block  -- Binary Code -> Segment 7 Code 
Begin 
       --gfedcba 
  SEG <=   "0111111" WHEN DB = 0 ELSE 
       "0000110" WHEN DB = 1 ELSE 
       "1011011" WHEN DB = 2 ELSE 
      "1001111" WHEN DB = 3 ELSE 
      "1100110" WHEN DB = 4 ELSE 
      "1101101" WHEN DB = 5 ELSE 
      "1111101" WHEN DB = 6 ELSE 
       "0000111" WHEN DB = 7 ELSE 
       "1111111" WHEN DB = 8 ELSE 
      "1101111" WHEN DB = 9 ELSE 
      "1111111"; 
End Block SEVEN_SEGMENT;        
END a;