segdecode.vhd

用vhdl实现ps2鼠标的源程序

library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_ARITH.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;

entity segdecode is
    Port ( datain : in std_logic_vector(3 downto 0);
           dataout : out std_logic_vector(6 downto 0));
end segdecode;

architecture Behavioral of segdecode is
signal hex : std_logic_vector(6 downto 0);
begin
  process (datain)
  begin
    case datain is			--	 0123456
			when "0000"	=>	hex <=  "0000001";
			when "0001"	=>	hex <=	"1001111";
			when "0010"	=>	hex <=	"0010010"; 
			when "0011"	=>	hex <=	"0000110"; 
			when "0100"	=>	hex <=	"1001100"; 
			when "0101"	=>	hex <=	"0100100";
			when "0110"	=>	hex <=	"0100000";
			when "0111"	=>	hex <=	"0001111";
			when "1000"	=>	hex <=	"0000000";
			when "1001"	=>	hex <=	"0000100";
			when "1010"	=>	hex <=	"0001000";
			when "1011"	=>	hex <=	"1100000";
			when "1100"	=>	hex <=	"0110001";
			when "1101"	=>	hex <=	"1000010";
			when "1110"	=>	hex <=	"0110000";
			when "1111"	=>	hex <=	"0111000";
			when others =>	hex <=	"1111111";
	 end case;
  end process;
  dataout <= hex;

end Behavioral;