wancheckmux.vhd

此为一用VHDL编写的硬件游戏程序

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

entity wancheckmux is
port(din :in std_logic_vector(15 downto 0);
     sel :in std_logic_vector(3  downto 0);
     dout :out std_logic_vector(3 downto 0));
end wancheckmux;
architecture behave of wancheckmux is
begin
   dout<=din(15 downto 12)when sel="1111"else
         din(14 downto 11)when sel="1110"else
         din(13 downto 10)when sel="1101"else
         din(12 downto 9)when sel="1100"else
         din(11 downto 8)when sel="1011"else
         din(10 downto 7)when sel="1010"else
         din(9 downto 6)when sel="1001"else
         din(8 downto 5)when sel="1000"else
         din(7 downto 4)when sel="0111"else
         din(6 downto 3)when sel="0110"else
         din(5 downto 2)when sel="0101"else
         din(4 downto 1)when sel="0100"else
         din(3 downto 0);
end behave;