xianshi.vhd

来自「eda微波炉程序控制器 初学vhdl语言的控制程序设计」· VHDL 代码 · 共 37 行

--XIANSHI

LIBRARY IEEE;
USE IEEE.STD_LOGIC_1164.ALL;
USE IEEE.STD_LOGIC_UNSIGNED.ALL;
ENTITY XIANSHI IS
PORT(  CLK0  : IN STD_LOGIC;
       SEC_L,SEC_H,MIN_L,MIN_H : IN STD_LOGIC_VECTOR(6 DOWNTO 0);
       SEL : OUT STD_LOGIC_VECTOR(2 DOWNTO 0);
       DISPLAY  : OUT STD_LOGIC_VECTOR(6 DOWNTO 0)
);
END XIANSHI;

ARCHITECTURE A OF XIANSHI IS
SIGNAL TEMP1 : STD_LOGIC_VECTOR(2 DOWNTO 0);
 BEGIN
  PROCESS(CLK0)
   BEGIN
   IF CLK0'EVENT AND CLK0='1'THEN
    IF TEMP1>="011" THEN TEMP1<="000";
    ELSE
    TEMP1<=TEMP1+1;
    END IF;
   END IF;

sel<=TEMP1;
CASE TEMP1 IS
WHEN "000"=>DISPLAY<=SEC_L(6 DOWNTO 0);
WHEN "001"=>DISPLAY<=SEC_H(6 DOWNTO 0);
WHEN "010"=>DISPLAY<=MIN_L(6 DOWNTO 0);
WHEN "011"=>DISPLAY<=MIN_H(6 DOWNTO 0);
WHEN OTHERS=>DISPLAY<=(OTHERS=>'0');
END CASE;

END PROCESS;
END A;