switch.vhd

四个拨码开关

library IEEE;
use IEEE.STD_LOGIC_1164.all;
use IEEE.STD_LOGIC_unsigned.all;

entity switch is
   port(
        led1,led2,led3,led4   : out  std_logic;
        key1,key2,key3,key4   : in   std_logic
        );
end switch;

architecture lxf of switch is

begin
process(key1,key2,key3,key4)
begin

if(key1='0')then led1<='1';else led1<='0';end if;
if(key2='0')then led2<='1';else led2<='0';end if;
if(key3='0')then led3<='1';else led3<='0';end if;
if(key4='0')then led4<='1';else led4<='0';end if;

end process;

end lxf;