disp.vhd

（1）、自动售货机可以出售4种货物

library ieee;
use ieee.std_logic_1164.all;
use ieee.std_logic_arith.all;
use ieee.std_logic_unsigned.all;

entity disp is
port ( clk3  :in std_logic;                                      
       bcdmo :in std_logic_vector(3 downto 0);
       sel   :out std_logic_vector(2 downto 1);
       seg   :out std_logic_vector(6 downto 0);
       light :out std_logic_vector;
       dot   :out std_logic_vector);
end ;

architecture a of disp is
    signal f,f1,f2 :std_logic_vector(3 downto 0);
    signal segsig  :std_logic_vector(6 downto 0);
    signal selsig  :std_logic_vector(2 downto 1);
    signal numlet,l,dp :std_logic;
    signal temp        :integer range 0 to 10;
begin
p4:
    process
    begin
        if(bcdmo="0001")then
          f1<="0001";f2<="0000"; temp<=1; l<='0'; dp<='0';
        elsif(bcdmo="0010")then
          f1<="0101";f2<="0000"; temp<=5; l<='0'; dp<='0';
        elsif(bcdmo="0011")then
          f1<="0000";f2<="0001"; temp<=10; l<='0'; dp<='0';
        elsif(bcdmo="0101")then
          f2<="0000"; 
          case temp is
                   when 1=>f1<="0000"; l<='1'; dp<='0';
                   when 5=>f1<="0100"; l<='1'; dp<='0';
                   when 10=>f1<="1001"; l<='1'; dp<='0';
                   when others=>f1<="0000"; l<='0'; dp<='1';
          end case;
        elsif(bcdmo="0110")then
            f2<="0000";
            case temp is
                   when 1=>f1<="0001"; l<='0'; dp<='1';
                   when 5=>f1<="0010"; l<='1'; dp<='0';
                   when 10=>f1<="0111"; l<='1'; dp<='0';
                   when others=>f1<="0000"; l<='0'; dp<='1';
           end case;
        elsif(bcdmo="0111")then
            f2<="0000";
            case temp is
                   when 1=>f1<="0001"; l<='0'; dp<='1';
                   when 5=>f1<="0101"; l<='0'; dp<='1';
                   when 10=>f1<="0011"; l<='1'; dp<='0';
                   when others=>f1<="0000"; l<='0'; dp<='1';
            end case;
        else
             f2<="0000";f1<="0000"; l<='0'; dp<='0'; temp<=0;
        end if;
        end process p4;
p5:
       process(clk3)
       begin
            if(clk3'event and clk3='1')then
                if(numlet='0')then
                    f<=f1;selsig(2 downto 0)<="10";
                else
                    f<=f2;selsig(2 downto 0)<="01";
                end if;
               numlet<=not numlet;
            end if;
            case f is
                when "0000"=>segsig(6 downto 0)<="1111110";
                when "0001"=>segsig(6 downto 0)<="0110000";
                when "0010"=>segsig(6 downto 0)<="1101101";
                when "0011"=>segsig(6 downto 0)<="1111001";
                when "0100"=>segsig(6 downto 0)<="0110011";
                when "0101"=>segsig(6 downto 0)<="1011011";
                when "0110"=>segsig(6 downto 0)<="1011111";
                when "0111"=>segsig(6 downto 0)<="1110000";
                when "1001"=>segsig(6 downto 0)<="1111011";
                when others=>segsig(6 downto 0)<="0000000";
           end case;
        end process p5;
sel<=selsig;
seg(6 downto 0)<=segsig(6 downto 0);
light<=1;
dot<=dp;
end;