矩阵键盘控制接口电路

1、电子信息工程 专业 年 月 日实验名称矩阵键盘控制接口电路指导教师姓 名年级学号成绩一、 预习部分1. 实验目的2. 实验基本原理3. 主要仪器设备（含必要的元器件、工具）实验原理：扫描信号为 BCOM8.1，在BCOM8.1前已接有一个3-8译码器，3-8译码器的输入为SEL0SEL3。当3-8译码器的输入为“000” 时，即BCOM1为0，其他位为1，我们按下第一排第一键，此时KIN0输出0，KIN1KIN3输出全为1，按下第二排第二键 时，KIN1输出0，其他输出1；当3-8译码器输入为001时，即BCOM2为0，我们按下第一排第二键，此时KIN0输出 0，KIN1KIN3输出全为1，同

2、理其他键依此类推。键盘上的每个按键就是一个开关，当某键被按下时，该按键的接点会呈现0状 态，反之为1。扫描信号为SEL2.0进入3-8译码器，再从译码器输出到键盘，所以第一次只能扫描一排，依此周而复始。按键位置与数码的关系 如表40-1所示。若从KIN3.0输出的皆为1时，表示没有按键按下，代表该列没有按键被按下，则不进行按键编码的操作，反之，如果 有被按下时，则应将KIN3.0读出的值送到译码电路进行编码。表40-1 按键位置与数码关系SEL2SEL0 KIN3KIN0 对应的按键000 1110 01101 61011 LAST0111 CTRL001 1110 11101 71011 S

3、TEP0111 EMPTY1010 1110 21101 REG1011 C0111 EMPTY2011 1110 31101 EXEC1011 D0111 EMPTY3100 1110 MEM1011 E0111 EMPTY4101 1110 ESC1101 91011 F0111 SHIFT110 1110 41101 A1011 NEXT0111 NONE111 1110 51101 B1011 ENTER0111 NONE1101 8实验内容：（1） 按键的去抖：消抖动电路：（2） 时钟产生：library ieee;use ieee.std_logic_1164.all;entity

4、 div is port(clr,clk: in bit; q: buffer bit);end div;architecture art of div is begin process(clr,clk) variable count: integer range 0 to 12499; begin if (clk='1' and clk'event) then if clr='1' then count:=0; elsif count=12499 then count:=0; q<=not q; else count:=count+1; end

5、if; end if; end process;end art;（2）仿真图（3） 键盘扫描译码电路：library ieee;use ieee.std_logic_1164.all;use ieee.std_logic_unsigned.all;entity keyboard4_4 is port( rst : in std_logic; clk : in std_logic; keyin : in std_logic_vector(3 downto 0); scan : out std_logic_vector(3 downto 0); leds : out std_logic_vecto

6、r(3 downto 0) );end keyboard4_4;architecture keyboard4_4_arch of keyboard4_4 is signal clkfrq : std_logic; signal cntscn : std_logic_vector(1 downto 0); signal scnlin : std_logic_vector(3 downto 0); signal cntfrq : std_logic_vector(14 downto 0); -signal cntfrq : std_logic_vector(3 downto 0); signal

7、lednum : std_logic_vector(7 downto 0);begin process(rst,clk, clkfrq) begin if rst = '0' then clkfrq <= '0' cntfrq <= (others=>'0'); elsif clk'event and clk = '1' then if cntfrq = "110000110101000" then -if cntfrq = "1111" then cntfrq &

8、lt;= (others => '0'); clkfrq <= not clkfrq; else cntfrq <= cntfrq + 1; end if; end if; end process; process(rst,clkfrq) begin if rst = '0' then cntscn <= "00" elsif clkfrq'event and clkfrq = '1' then if cntscn = "11" then cntscn <= "

9、;00" else cntscn <= cntscn+1; end if; case cntscn is when "00" => scnlin <= "0001" when "01" => scnlin <= "0010" when "10" => scnlin <= "0100" when "11" => scnlin <= "1000" when others =&g

10、t; null; end case; end if; end process; process(rst, clkfrq) begin if(rst = '0' ) then leds <= "1111" elsif clkfrq'event and clkfrq = '0' then case lednum is when "00010001" => leds <= "0000" when "00010010" => leds <= "

11、0001" when "00010100" => leds <= "0010" when "00011000" => leds <= "0011" when "00100001" => leds <= "0100" when "00100010" => leds <= "0101" when "00100100" => leds <= "

12、0110" when "00101000" => leds <= "0111" when "01000001" => leds <= "1000" when "01000010" => leds <= "1001" when "01000100" => leds <= "1010" when "01001000" => leds <= "

13、1011" when "10000001" => leds <= "1100" when "10000010" => leds <= "1101" when "10000100" => leds <= "1110" when "10001000" => leds <= "1111" when others => null; end case; end if; end pro

14、cess; scan <= scnlin; lednum <= scnlin&keyin; end keyboard4_4_arch;（4）按键显示电路：LIBRARY IEEE;USE IEEE.STD_LOGIC_1164.ALL;USE IEEE.STD_LOGIC_ARITH.ALL;USE IEEE.STD_LOGIC_UNSIGNED.ALL;ENTITY DELED IS PORT(SELTMP: IN STD_LOGIC_VECTOR(2 DOWNTO 0); BCDIN: IN STD_LOGIC_VECTOR(31 DOWNTO 0);SEGOUT: O

15、UT STD_LOGIC_VECTOR(6 DOWNTO 0)END DELED;ARCHITECTURE ART1 OF DELED ISSIGNAL DB:STD_LOGIC_VECTOR(3 DOWNTO 0)SIGNAL SEG:STD_LOGIC_VECTOR(6 DOWNTO 0)BEGINSEGOUT<=SEG;MULTIPLEXER:BLOCKBEGINDB<=BCDIN(3 DOWNTO 0)WHEN SETMP =0ELSEBCDIN(7 DOWNTO 4)WHEN SETMP =0ELSEBCDIN(11 DOWNTO 8)WHEN SETMP =0ELSEB

16、CDIN(15 DOWNTO 12)WHEN SETMP =0ELSEBCDIN(19 DOWNTO 16)WHEN SETMP =0ELSEBCDIN(23 DOWNTO 20)WHEN SETMP =0ELSEBCDIN(27 DOWNTO 24)WHEN SETMP =0ELSEBCDIN(31 DOWNTO 28);END ;SEVEN_SEGMENT:SEG<="1111110"when num="0000"else "0110000"when num="0001"else "1101101"when num="0010"else "1111001"when num="0011"else "0110011"when num="0100"else "1011011"when num="0101"else "1011111"