kcoun10.vhd

来自「里面有一个很实用的源码,数字引爆密码设计」· VHDL 代码 · 共 28 行

LIBRARY IEEE;
USE IEEE.std_logic_1164.ALL;
USE IEEE.std_logic_unsigned.ALL;

ENTITY kcoun10 IS
           PORT (A  : IN  std_logic;
                 B  : OUT  std_logic);
END kcoun10;

ARCHITECTURE kcoun10_arc OF kcoun10 IS
     SIGNAL  counter  : std_logic;
BEGIN
     PROCESS(A)
     VARIABLE  counter1  : integer RANGE 0 TO 15;
     CONSTANT  md  : integer := 5;
     BEGIN
          IF (A'event AND A = '1') THEN
             IF (counter1 = md) THEN
                 counter1 := 0;
                 counter <= NOT counter;
                 B <= counter;
             END IF;
             counter1 := counter1+1;
          END IF; 
     END PROCESS;
END kcoun10_arc;