decode47.vhd

用 VHDL语言实现闹钟功能

library ieee;
use ieee.std_logic_1164.all;
entity decode47 is 
  port (adr :in std_logic_vector(3 downto 0);
        decodeout :out std_logic_vector(6 downto 0));
end decode47;

architecture truthtable of decode47 is
  begin
  process(adr)
    begin 
           case adr is
                when "0000"=> decodeout<="1111110";
                when "0001"=> decodeout<="0110000";
                when "0010"=> decodeout<="1101101";
                when "0011"=> decodeout<="1111001";
                when "0100"=> decodeout<="0110011";
                when "0101"=> decodeout<="1011011";
                when "0110"=> decodeout<="1011111";
                when "0111"=> decodeout<="1110000";
                when "1000"=> decodeout<="1111111";
                when others=> decodeout<="1111011";
            end case;
  end process;
end truthtable;