cb.vhd

来自「用PLC程序编写十字路口的交通灯」· VHDL 代码 · 共 16 行

library ieee;
use ieee.std_logic_1164.all;
entity cb is
port(clk:in std_logic;
     q:buffer std_logic);
end;
architecture behave of cb is
begin 
process(clk)
begin
if clk'event and clk='1' then
q<=not q;
end if;
end process;
end behave;