hsata.vhd

Vhdl cod for a bus.For sp2e

        ld <= '1';
        WAIT UNTIL clk='1';
        ld <= '0';
    END SendALIGN;

    PROCEDURE encode (rd : INOUT std_logic;
                       byte : IN std_logic_vector(7 DOWNTO 0);
                       SIGNAL code : OUT std_logic_vector(9 DOWNTO 0)) IS 
    VARIABLE temp   : std_logic_vector(9 DOWNTO 0);
    VARIABLE x,y    : INTEGER;    
    VARIABLE rd6    : std_logic;    
    BEGIN      
        x := to_nat(byte(4 DOWNTO 0));
        y := to_nat(byte(7 DOWNTO 5));
        -- 5B/6B
        CASE x IS 
            WHEN 0 | 1 | 2 | 4 | 8 | 15 | 16 | 23 | 24 | 27 | 29 | 30 | 31 => rd6 := NOT rd;
            WHEN others => rd6 := rd;
        END CASE;
        IF rd = '0' THEN
            CASE x IS 
                WHEN 0  => temp(5 DOWNTO 0) := "111001";
                WHEN 1  => temp(5 DOWNTO 0) := "101110";
                WHEN 2  => temp(5 DOWNTO 0) := "101101";
                WHEN 3  => temp(5 DOWNTO 0) := "100011";
                WHEN 4  => temp(5 DOWNTO 0) := "101011";
                WHEN 5  => temp(5 DOWNTO 0) := "100101"; 
                WHEN 6  => temp(5 DOWNTO 0) := "100110"; 
                WHEN 7  => temp(5 DOWNTO 0) := "000111"; 
                WHEN 8  => temp(5 DOWNTO 0) := "100111"; 
                WHEN 9  => temp(5 DOWNTO 0) := "101001"; 
                WHEN 10 => temp(5 DOWNTO 0) := "101010"; 
                WHEN 11 => temp(5 DOWNTO 0) := "001011"; 
                WHEN 12 => temp(5 DOWNTO 0) := "101100"; 
                WHEN 13 => temp(5 DOWNTO 0) := "001101"; 
                WHEN 14 => temp(5 DOWNTO 0) := "001110"; 
                WHEN 15 => temp(5 DOWNTO 0) := "111010"; 
                WHEN 16 => temp(5 DOWNTO 0) := "110110"; 
                WHEN 17 => temp(5 DOWNTO 0) := "110001"; 
                WHEN 18 => temp(5 DOWNTO 0) := "110010"; 
                WHEN 19 => temp(5 DOWNTO 0) := "010011"; 
                WHEN 20 => temp(5 DOWNTO 0) := "110100"; 
                WHEN 21 => temp(5 DOWNTO 0) := "010101"; 
                WHEN 22 => temp(5 DOWNTO 0) := "010110"; 
                WHEN 23 => temp(5 DOWNTO 0) := "010111"; 
                WHEN 24 => temp(5 DOWNTO 0) := "110011"; 
                WHEN 25 => temp(5 DOWNTO 0) := "011001"; 
                WHEN 26 => temp(5 DOWNTO 0) := "011010"; 
                WHEN 27 => temp(5 DOWNTO 0) := "011011"; 
                WHEN 28 => temp(5 DOWNTO 0) := "011100"; 
                WHEN 29 => temp(5 DOWNTO 0) := "011101"; 
                WHEN 30 => temp(5 DOWNTO 0) := "011110";
                WHEN 31 => temp(5 DOWNTO 0) := "110101"; 
                WHEN others =>
            END CASE;
        ELSE                
            CASE x IS 
                WHEN 0  => temp(5 DOWNTO 0) := "000110";  
                WHEN 1  => temp(5 DOWNTO 0) := "010001";  
                WHEN 2  => temp(5 DOWNTO 0) := "010010";  
                WHEN 3  => temp(5 DOWNTO 0) := "100011";  
                WHEN 4  => temp(5 DOWNTO 0) := "010100";  
                WHEN 5  => temp(5 DOWNTO 0) := "100101";  
                WHEN 6  => temp(5 DOWNTO 0) := "100110";  
                WHEN 7  => temp(5 DOWNTO 0) := "111000";  
                WHEN 8  => temp(5 DOWNTO 0) := "011000";  
                WHEN 9  => temp(5 DOWNTO 0) := "101001";  
                WHEN 10 => temp(5 DOWNTO 0) := "101010";  
                WHEN 11 => temp(5 DOWNTO 0) := "001011";  
                WHEN 12 => temp(5 DOWNTO 0) := "101100";  
                WHEN 13 => temp(5 DOWNTO 0) := "001101";  
                WHEN 14 => temp(5 DOWNTO 0) := "001110";  
                WHEN 15 => temp(5 DOWNTO 0) := "000101";  
                WHEN 16 => temp(5 DOWNTO 0) := "001001";  
                WHEN 17 => temp(5 DOWNTO 0) := "110001";  
                WHEN 18 => temp(5 DOWNTO 0) := "110010";  
                WHEN 19 => temp(5 DOWNTO 0) := "010011";  
                WHEN 20 => temp(5 DOWNTO 0) := "110100";  
                WHEN 21 => temp(5 DOWNTO 0) := "010101";  
                WHEN 22 => temp(5 DOWNTO 0) := "010110";  
                WHEN 23 => temp(5 DOWNTO 0) := "101000";  
                WHEN 24 => temp(5 DOWNTO 0) := "001100";  
                WHEN 25 => temp(5 DOWNTO 0) := "011001";  
                WHEN 26 => temp(5 DOWNTO 0) := "011010";  
                WHEN 27 => temp(5 DOWNTO 0) := "100100";  
                WHEN 28 => temp(5 DOWNTO 0) := "011100";  
                WHEN 29 => temp(5 DOWNTO 0) := "100010";  
                WHEN 30 => temp(5 DOWNTO 0) := "100001";  
                WHEN 31 => temp(5 DOWNTO 0) := "001010";  
                WHEN others =>
            END CASE;
        END IF;
        
        IF rd6 = '0' THEN
            CASE y IS 
                WHEN 0  => temp(9 DOWNTO 6) := "1101";
                WHEN 1  => temp(9 DOWNTO 6) := "1001";
                WHEN 2  => temp(9 DOWNTO 6) := "1010";
                WHEN 3  => temp(9 DOWNTO 6) := "0011";
                WHEN 4  => temp(9 DOWNTO 6) := "1011";
                WHEN 5  => temp(9 DOWNTO 6) := "0101";
                WHEN 6  => temp(9 DOWNTO 6) := "0110";
                WHEN 7  => 
                    IF temp(5)='1' AND temp(4)='1' THEN -- e=i=1
                        temp(9 DOWNTO 6) := "1110";     -- A7
                    ELSE 
                        temp(9 DOWNTO 6) := "0111";     -- P7
                    END IF;    
                WHEN others =>
             END CASE;  
        ELSE
            CASE y IS 
                WHEN 0  => temp(9 DOWNTO 6) := "0010";
                WHEN 1  => temp(9 DOWNTO 6) := "1001";
                WHEN 2  => temp(9 DOWNTO 6) := "1010";
                WHEN 3  => temp(9 DOWNTO 6) := "1100";
                WHEN 4  => temp(9 DOWNTO 6) := "0100";
                WHEN 5  => temp(9 DOWNTO 6) := "0101";
                WHEN 6  => temp(9 DOWNTO 6) := "0110";
                WHEN 7  => 
                    IF temp(5)='0' AND temp(4)='0' THEN -- e=i=0
                        temp(9 DOWNTO 6) := "0001";     -- A7
                    ELSE 
                        temp(9 DOWNTO 6) := "1000";     -- P7
                    END IF;    
                WHEN others =>
             END CASE;  
        END IF;    

        CASE y IS 
            WHEN 0 | 4 | 7 => rd := NOT rd6;
            WHEN others => rd := rd6;
        END CASE;

        code <= temp;
--        RETURN temp;    
    END encode;


    FUNCTION decode (rd : IN std_logic;
                     code : IN std_logic_vector(9 DOWNTO 0)) RETURN std_logic_vector IS --(9 DOWNTO 0) IS
    VARIABLE temp   : std_logic_vector(9 DOWNTO 0);
    VARIABLE x      : std_logic_vector(4 DOWNTO 0);
    VARIABLE y      : std_logic_vector(2 DOWNTO 0);    
    VARIABLE rd6    : std_logic;
    VARIABLE err    : std_logic;               
    VARIABLE ctrl   : std_logic;               
    
    BEGIN         
        err := '0';      
        ctrl := '0';        
        IF rd = '0' THEN                
            IF code(5 DOWNTO 0) = "111100" THEN       -- K28.3 
                ctrl := '1';                                   
                rd6 := '1';                                    
                x := "11100";                                  
            ELSIF code(5 DOWNTO 0) = "111100" THEN    -- K28.5 
                ctrl := '1';
                rd6 := '1';
                x := "11100";
            ELSE
            CASE code(5 DOWNTO 0) IS 
                WHEN "111001"  => x := "00000"; rd6 := '1';
                WHEN "101110"  => x := "00001"; rd6 := '1';
                WHEN "101101"  => x := "00010"; rd6 := '1';
                WHEN "100011"  => x := "00011"; rd6 := '0';
                WHEN "101011"  => x := "00100"; rd6 := '1';
                WHEN "100101"  => x := "00101"; rd6 := '0';
                WHEN "100110"  => x := "00110"; rd6 := '0';
                WHEN "000111"  => x := "00111"; rd6 := '0';
                WHEN "100111"  => x := "01000"; rd6 := '1';
                WHEN "101001"  => x := "01001"; rd6 := '0';
                WHEN "101010"  => x := "01010"; rd6 := '0';
                WHEN "001011"  => x := "01011"; rd6 := '0';
                WHEN "101100"  => x := "01100"; rd6 := '0';
                WHEN "001101"  => x := "01101"; rd6 := '0';
                WHEN "001110"  => x := "01110"; rd6 := '0';
                WHEN "111010"  => x := "01111"; rd6 := '1';
                WHEN "110110"  => x := "10000"; rd6 := '1';
                WHEN "110001"  => x := "10001"; rd6 := '0';
                WHEN "110010"  => x := "10010"; rd6 := '0';
                WHEN "010011"  => x := "10011"; rd6 := '0';
                WHEN "110100"  => x := "10100"; rd6 := '0';
                WHEN "010101"  => x := "10101"; rd6 := '0';
                WHEN "010110"  => x := "10110"; rd6 := '0';
                WHEN "010111"  => x := "10111"; rd6 := '1';
                WHEN "110011"  => x := "11000"; rd6 := '1';
                WHEN "011001"  => x := "11001"; rd6 := '0';
                WHEN "011010"  => x := "11010"; rd6 := '0';
                WHEN "011011"  => x := "11011"; rd6 := '1';
                WHEN "011100"  => x := "11100"; rd6 := '0';
                WHEN "011101"  => x := "11101"; rd6 := '1';
                WHEN "011110"  => x := "11110"; rd6 := '1';
                WHEN "110101"  => x := "11111"; rd6 := '1';
                WHEN others => err := '1';
            END CASE;
            END IF;
        ELSE
            IF code(5 DOWNTO 0) = "000011" THEN         -- K28.3
                ctrl := '1';
                rd6 := '0';
                x := "11100";
            ELSIF code(5 DOWNTO 0) = "000011" THEN      -- K28.5
                ctrl := '1';
                rd6 := '0';
                x := "11100";
            ELSE
            CASE code(5 DOWNTO 0) IS 
                WHEN "000110"  => x := "00000"; rd6 := '0';
                WHEN "010001"  => x := "00001"; rd6 := '0';
                WHEN "010010"  => x := "00010"; rd6 := '0';
                WHEN "100011"  => x := "00011"; rd6 := '1';
                WHEN "010100"  => x := "00100"; rd6 := '0';
                WHEN "100101"  => x := "00101"; rd6 := '1';
                WHEN "100110"  => x := "00110"; rd6 := '1';
                WHEN "111000"  => x := "00111"; rd6 := '1';
                WHEN "011000"  => x := "01000"; rd6 := '0';
                WHEN "101001"  => x := "01001"; rd6 := '1';
                WHEN "101010"  => x := "01010"; rd6 := '1';
                WHEN "001011"  => x := "01011"; rd6 := '1';
                WHEN "101100"  => x := "01100"; rd6 := '1';
                WHEN "001101"  => x := "01101"; rd6 := '1';
                WHEN "001110"  => x := "01110"; rd6 := '1';
                WHEN "000101"  => x := "01111"; rd6 := '0';
                WHEN "001001"  => x := "10000"; rd6 := '0';
                WHEN "110001"  => x := "10001"; rd6 := '1';
                WHEN "110010"  => x := "10010"; rd6 := '1';
                WHEN "010011"  => x := "10011"; rd6 := '1';
                WHEN "110100"  => x := "10100"; rd6 := '1';
                WHEN "010101"  => x := "10101"; rd6 := '1';
                WHEN "010110"  => x := "10110"; rd6 := '1';
                WHEN "101000"  => x := "10111"; rd6 := '0';
                WHEN "001100"  => x := "11000"; rd6 := '0';
                WHEN "011001"  => x := "11001"; rd6 := '1';
                WHEN "011010"  => x := "11010"; rd6 := '1';
                WHEN "100100"  => x := "11011"; rd6 := '0';
                WHEN "011100"  => x := "11100"; rd6 := '1';
                WHEN "100010"  => x := "11101"; rd6 := '0';
                WHEN "100001"  => x := "11110"; rd6 := '0';
                WHEN "001010"  => x := "11111"; rd6 := '0';
                WHEN others => err := '1';
            END CASE;   
            END IF;
        END IF;
        IF rd6 = '0' THEN        
            CASE code(9 DOWNTO 6) IS 
                WHEN "1101"  => y := "000"; 
                WHEN "1001"  => y := "001"; 
                WHEN "1010"  => y := "010"; 
                WHEN "0011"  => y := "011"; 
                WHEN "1011"  => y := "100"; 
                WHEN "0101"  => y := "101"; 
                WHEN "0110"  => y := "110"; 
                WHEN "0111"  => y := "111"; 
                WHEN "1110"  => y := "111"; 
                WHEN others => err := '1';
            END CASE;                      
        ELSE        
            CASE code(9 DOWNTO 6) IS 
                WHEN "0010"  => y := "000"; 
                WHEN "1001"  => y := "001"; 
                WHEN "1010"  => y := "010"; 
                WHEN "1100"  => y := "011"; 
                WHEN "0100"  => y := "100"; 
                WHEN "0101"  => y := "101"; 
                WHEN "0110"  => y := "110"; 
                WHEN "1000"  => y := "111"; 
                WHEN "0001"  => y := "111"; 
                WHEN others => err := '1';
            END CASE;  
        END IF;
        temp := ctrl & err & y & x;            
        RETURN temp;    
    END decode;
    
    FUNCTION new_rd (rd : IN std_logic;
                     code : IN std_logic_vector(9 DOWNTO 0)) RETURN std_logic IS
    VARIABLE n_ones   : INTEGER;
    VARIABLE rd6, rd4 : std_logic;
    BEGIN      
    -- NOTICE rd = 0 is negative running disparity
    --        rd = 1 is positive running disparity
    
    -- six-bit sub-block
        n_ones := 0;
        FOR i IN 0 TO 5 LOOP
            IF code(i) = '1' THEN
                n_ones := n_ones + 1;
            END IF;
        END LOOP;
        IF (n_ones > 3) OR code(5 DOWNTO 0) = "111000" THEN 
            rd6 := '1';
        ELSIF (n_ones < 3) OR code(5 DOWNTO 0) = "000111" THEN
            rd6 := '0';
        ELSE
            rd6 := rd;