transform.vhd

本程序是一个用VHDL编写的数码管扫描显示控制器的设计与实现的程序

--Declaration of using IEEE Library
Library IEEE; 
--Declaration of using STD_LOGIC_1164 package          
Use IEEE.std_logic_1164.all; 
--Declaration of using STD_LOGIC_UNSIGNED package  
Use IEEE.std_logic_unsigned.all;
 --Declaration of Entity transform
Entity transform is      
    Port( ai:in std_logic_vector(3 downto 0);   --Declaration of in port
          b:out std_logic_vector(6 downto 0));   --Declaration of out ports
End transform;
 --Declaration of Architecture bav
Architecture bav of transform is   
 Begin
   process(ai)
     begin
      case ai is
       when "0000"=>b<="1111110";
       when "0001"=>b<="0110000";
       when "0010"=>b<="1101101";
       when "0011"=>b<="1111001";
       when "0100"=>b<="0110011";
       when "0101"=>b<="1011011";
       when "0110"=>b<="1011111";
       when "0111"=>b<="1110000";
       when "1000"=>b<="1111111";
       when "1001"=>b<="1111011";
       when others=>b<="0000000";
    end case;
 end process;
End bav;