本科学生综合性实验报告

学号 094090xxx 姓名 王 赟

学院 物电学院 专业、班级 物理09物理D班 实验课程名称 数电实验 教师及职称 张超 开课学期 至 填报时间年月日

云南师范大学教务处编印

 

第二篇：实验四 译码器

实验名称：组合逻辑VHDL设计----译码器

班级：09通信1   学号：09811106   姓名：顾礼萍

一、用WITH-SELECT语句实现2-4译码器

1.实体框图

 

2.程序设计

LIBRARY IEEE;

USE IEEE.STD_LOGIC_1164.ALL;

ENTITY DECODER24B IS

 PORT(A1,A0:IN STD_LOGIC;

       Y:OUT STD_LOGIC_VECTOR(3 DOWNTO 0));

END ENTITY DECODER24B;

ARCHITECTURE ONE OF DECODER24B IS

SIGNAL S: STD_LOGIC_VECTOR(1 DOWNTO 0);

 BEGIN

S<=A1&A0;

    WITH S SELECT

    Y<="1110" WHEN"00",

       "1101" WHEN"01",

       "1011" WHEN"10",

       "0111" WHEN"11",

       "ZZZZ" WHEN OTHERS;

END ARCHITECTURE ONE;

3.仿真波形图

 

4.仿真波形分析

二、用WITH-SELECT语句实现带使能端的3-8译码器

1.实体框图

2.程序设计

LIBRARY IEEE;

USE IEEE.STD_LOGIC_1164.ALL;

ENTITY DECODER38B IS

 PORT(A2,A1,A0:IN STD_LOGIC;

      S3,S2,S1:IN STD_LOGIC;

      Y:OUT STD_LOGIC_VECTOR(7 DOWNTO 0));

END ENTITY DECODER38B;

ARCHITECTURE ONE OF DECODER38B IS

SIGNAL G: STD_LOGIC_VECTOR(4DOWNTO 0);

 BEGIN

    G<=S1&(S2 AND S3)&A2&A1&A0;

    WITH G SELECT

    Y<="11111110" WHEN"10000",

       "11111101" WHEN"10001",

       "11111011" WHEN"10010",

       "11110111" WHEN"10011",

       "11101111" WHEN"10100",

       "11011111" WHEN"10101",

       "10111111" WHEN"10110", 

       "01111111" WHEN"10111",

       "ZZZZZZZZ" WHEN OTHERS;

END ARCHITECTURE ONE;

3.仿真波形图

4.仿真波形分析

三、用WITH-SELECT语句实现驱动共阳极数码管七段显示译码器

1.实体框图

2.程序设计

LIBRARY IEEE;

USE IEEE.STD_LOGIC_1164.ALL;

ENTITY DECODER7B IS

 PORT(A:IN STD_LOGIC_VECTOR(3 DOWNTO 0);

      DOUT:OUT STD_LOGIC_VECTOR(6 DOWNTO 0)

END ENTITY DECODER7B;

ARCHITECTURE ONE OF DECODER7B IS

SIGNAL S: STD_LOGIC_VECTOR(3 DOWNTO 0);

 BEGIN

    S<=A3&A2&A1&A0;

    WITH S SELECT

    Y<="1111111" WHEN"0000",

       "1111001" WHEN"0001",

       "0100100" WHEN"0010",

       "0110000" WHEN"0011",

       "0011001" WHEN"0100",

       "0010010" WHEN"0101",

       "0000010" WHEN"0110", 

       "1111000" WHEN"0111",

       "0000000" WHEN"1000",

       "0010000" WHEN"1001",

       "ZZZZZZZ" WHEN OTHERS;

END ARCHITECTURE ONE;

3.仿真波形图

4.仿真波形分析

思考题

1.  设计共阴极七段显示译码器。

LIBRARY IEEE;

USE IEEE.STD_LOGIC_1164.ALL;

ENTITY DECODER7B IS

 PORT(A:IN STD_LOGIC_VECTOR(3 DOWNTO 0);

      DOUT:OUT STD_LOGIC_VECTOR(6 DOWNTO 0)

END ENTITY DECODER7B;

ARCHITECTURE ONE OF DECODER7B IS

SIGNAL S: STD_LOGIC_VECTOR(3 DOWNTO 0);

 BEGIN

    S<=A3&A2&A1&A0;

    WITH S SELECT

    Y<="0000000" WHEN"0000",

       "0000110" WHEN"0001",

       "1011011" WHEN"0010",

       "1001111" WHEN"0011",

       "1100110" WHEN"0100",

       "1101101" WHEN"0101",

       "1111101" WHEN"0110", 

       "0000111" WHEN"0111",

       "1111111" WHEN"1000",

       "1101111" WHEN"1001",

       "ZZZZZZZ" WHEN OTHERS;

END ARCHITECTURE ONE;

2.  设计2进制变换为格雷码的码制变换译码器。

LIBRARY IEEE;

USE IEEE.STD_LOGIC_1164.ALL;

USE IEEE.STD_LOGIC_UNSIGNED.ALL;

USE IEEE.STD_LOGIC_ARITH.ALL;

ENTITY  DECODDER 7C IS

GENERIC(n:INTEGER :=4);

PORT(

     NORM : IN STD_LOGIC_VECTOR(N-1 DOWNTO 0);

     GREY: OUT STD_LOGIC_VECTOR(N-1 DOWNTO 0));

END  ENTITY  DECODDER 7C ;

ARCHITECTURE ONE  OF DECODDER 7C  IS

SIGNAL TEMP_NORMAL: STD_LOGIC_VECTOR(N-1 DOWNTO 0);

SIGNAL TEMP_GREY : STD_LOGIC_VECTOR(N-1 DOWNTO 0);

BEGIN

PROCESS(NORM)

BEGIN

TEMP_NORMAL <= NORM;

TEMP_GREY(n-1) <=TEMP_NORMAL(N-1)

FOR I IN N-2 DOWNTO 0 LOOP

TEMP_GREY(I) <= TEMP_NORMAL(I+1) XOR  TEMP_NORMAL(I);

END LOOP;

GREY <= TEMP_GREY;

END PROCESS;

END ONE;