----------------------------
例1:FPGA驱动LED静态显示
--文件名:decoder.vhd
--功能:译码输出模块,LED为共阳接法
--最后修改日期:2004.3.24
library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_ARITH.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;
entity decoder is
Port (seg:in std_logic_vector(3 downto 0 ); --四位二进制码输入
q3:out std_logic_vector(6 downto 0) ); --输出LED七段码
end decoder;
architecture Behavioral of decoder is
begin
process(seg)
begin
case seg is
when "0000" => q3<="0000001";--0
when "0001" => q3<="1001111";--1
when "0010" => q3<="0010010";--2
when "0011" => q3<="0000110";--3
when "0100" => q3<="1001100" --4
when "0101" => q3<="0100100";--5
when "0110" => q3<="0100000";--6
when "0111" => q3<="0001111";--7
when "1000" => q3<="0000000";--8
when "1001" => q3<="0000100";--9
when others => q3<="1111111";
end case;
end process;
end Behavioral;