动态扫描数码管显示VHDL

USE IEEE.STD_LOGIC_11.ALL;

USE IEEE.STD_LOGIC_UNSIGNED.ALL;

ENTITY SAOMIAO IS 

    PORT(CLK: IN STD_LOGIC;

        S1, S2, S3, S4, S5, S6: IN STD_LOGIC_VECTOR(3 DOWNTO 0);

        WEI: OUT STD_LOGIC_VECTOR(5 DOWNTO 0);

        LED: OUT STD_LOGIC_VECTOR(6 DOWNTO 0));

END ENTITY;

ARCHITECTURE behave OF SAOMIAO IS

    SIGNAL CNT6 : INTEGER RANGE 0 TO 5 := 0;

    SIGNAL SHUJU: STD_LOGIC_VECTOR(3 DOWNTO 0);

BEGIN 

    PRO1:PROCESS(CLK)

    BEGIN

        IF CLK'EVENT AND CLK = '1' THEN

         CNT6 <= CNT6 + 1;

            CASE CNT6 IS

             WHEN 0 => WEI <= "000001"; SHUJU <= S1;

             WHEN 1 => WEI <= "000010"; SHUJU <= S2;

             WHEN 2 => WEI <= "000100"; SHUJU <= S3;

             WHEN 3 => WEI <= "001000"; SHUJU <= S4;

             WHEN 4 => WEI <= "010000"; SHUJU <= S5;

             WHEN 5 => WEI <= "100000"; SHUJU <= S6;

             WHEN OTHERS => NULL;

            END CASE;

        END IF;

    END PROCESS;

    PRO2: PROCESS(SHUJU)

    BEGIN

        CASE SHUJU IS

         WHEN "0000" => LED<= "1111110" ; --- 0

         WHEN "0001" => LED<= "0110000" ; --- 1

         WHEN "0010" => LED<= "1101101" ; --- 2

         WHEN "0011" => LED<= "1111001" ; --- 3

         WHEN "0100" => LED<= "0110011" ; --- 4

         WHEN "0101" => LED<= "1011011" ; --- 5

         WHEN "0110" => LED<= "1011111" ; --- 6

         WHEN "0111" => LED<= "1110000" ; --- 7

         WHEN "1000" => LED<= "1111111" ; --- 8

         WHEN "1001" => LED<= "1111011" ; --- 9

         WHEN others=> LED<= "0000000" ;

        END CASE;

    END PROCESS;

END ;