1、LED點陣屏上文字顯示實驗李宇 pb09013011實驗要求:在試驗板的8×8的LED點陣屏上分別顯示“PLD電子技術”。編程思想:1.首先定義控制LED點陣屏的端口組a,b,及時鐘和復位端口Port ( a : inout STD_LOGIC_VECTOR (7 downto 0;b : inout STD_LOGIC_VECTOR (7 downto 0;clk : in STD_LOGIC;reset : in STD_LOGIC;2.字的跳變顯示是通過改變整型變量m的值來選擇掃描的程序段3.對LED點陣屏的工作方式清楚,XUP板子上采用的是共陰極8x8點陣LED。8X8點陣L

2、ED結構如下圖所示 從圖中可以看出,8X8點陣共需要64個發光二極管組成,且每個發光二極管是放置在行線和列線的交叉點上,當對應的某一列置0電平,某一行置0電平,則相應的二極管就亮;本程序中是通過對行掃描,并對當前行中需要亮燈的列置0來實現顯示過程。示例程序段如下:if(count=N/8 thena<="11111111"b<="01111111"count<=count+1;elsif(count=N/4 thena<="11101111"b<="10111111"count<

3、=count+1;elsif(count=3*N/8 thena<="11101111"b<="11011111"count<=count+1;elsif(count=N/2thena<="11101111"b<="11101111"count<=count+1;elsif(count=N*5/8 thena<="11101111"b<="11110111"count<=count+1;elsif(count=N*3/4

4、thena<="11101111"b<="11111011"count<=count+1;elsif(count=7*N/8 thena<="11101111"b<="11111101"count<=count+1;elsif(count=Nthena<="11100011"b<="11111110"count<=0;VHDL代碼:- Company:- Engineer:- Create Date: 10:09:58 0

5、5/24/2012- Design Name:- Module Name: expp8 - Behavioral- Project Name:- Target Devices:- Tool versions:- Description:- Dependencies:- Revision:- Revision 0.01 - File Created- Additional Comments:-library IEEE;- Uncomment the following library declaration if instantiating- any Xilinx primitives in t

6、his code.-library UNISIM;entity expp8 isgeneric(N: integer :=16000;Port ( a : inout STD_LOGIC_VECTOR (7 downto 0;b : inout STD_LOGIC_VECTOR (7 downto 0;clk : in STD_LOGIC;reset : in STD_LOGIC;end expp8;architecture Behavioral of expp8 issignal count:INTEGER RANGE 0 to N:=0;-count用來對LED掃描分頻用 -count1用

7、來產生1HZ的分頻信號signal count1:INTEGER RANGE 0 to 49999999:=0;signal m:integer:=0;-用m的數值來選擇該掃描顯示那個字beginprocess(reset,clkbegin-復位時的表現為屏上的燈全部點亮if(reset='0' thena<="00000000"b<="00000000"count<=0;m<=0;count1<=0;elseif(rising_edge(clk thenif count1=49999999 then -一赫

8、茲的分頻信號產生m<=m+1;count1<=0;else count1<=count1+1;end if;-m=0時采用掃描的方式顯示第一個字母“P”if m=0 then-所選行中點亮的燈的時間為N/8個周期 if(count=N/8 thena<="11111111"b<="01111111"count<=count+1;elsif(count=N/4 thena<="11100111"b<="10111111"count<=count+1;elsif(c

9、ount=3*N/8 thena<="11101011"b<="11011111"count<=count+1;elsif(count=N/2thena<="11101011"b<="11101111"count<=count+1;elsif(count=N*5/8 thena<="11100111"b<="11110111"count<=count+1;elsif(count=N*3/4 thena<="

10、11101111"b<="11111011"count<=count+1;elsif(count=7*N/8 thena<="11101111"b<="11111101"count<=count+1;elsif(count=Nthena<="11101111"b<="11111110"count<=0;elsecount<=count+1;end if;-m=1時顯示“L”,時長同樣為1秒elsif m=1 thenif(count

11、=N/8 thena<="11111111"b<="01111111"count<=count+1;elsif(count=N/4 thena<="11101111"b<="10111111"count<=count+1;elsif(count=3*N/8 thena<="11101111"b<="11011111"count<=count+1;elsif(count=N/2thena<="11101111

12、"b<="11101111"count<=count+1;elsif(count=N*5/8 thena<="11101111"b<="11110111"count<=count+1;elsif(count=N*3/4 thena<="11101111"b<="11111011"count<=count+1;elsif(count=7*N/8 thena<="11101111"b<="111111

13、01"count<=count+1;elsif(count=Nthena<="11100011"b<="11111110"count<=0;elsecount<=count+1;end if;-m=2顯示“D”,時長為一秒 elsif m=2 thenif(count=N/8 thena<="11111111"b<="01111111"count<=count+1;elsif(count=N/4 thena<="11100111"b

14、<="10111111"count<=count+1;elsif(count=3*N/8 thena<="11101011"b<="11011111"count<=count+1;elsif(count=N/2thena<="11101101"b<="11101111"count<=count+1;elsif(count=N*5/8 thena<="11101101"b<="11110111"co

15、unt<=count+1;elsif(count=N*3/4 thena<="11101101"b<="11111011"count<=count+1;elsif(count=7*N/8 thena<="11101011"b<="11111101"count<=count+1;elsif(count=Nthena<="11100111"b<="11111110"count<=0;elsecount<=count

16、+1;end if;-m=3顯示“電”,時長為一秒elsif m=3 thenif(count=N/8 thena<="11111111"b<="01111111"count<=count+1;elsif(count=N/4 thena<="11101111"b<="10111111"count<=count+1;elsif(count=3*N/8 thena<="10000011"b<="11011111"count<=

17、count+1;elsif(count=N/2thena<="10000011"b<="11101111"count<=count+1;elsif(count=N*5/8 thena<="10000011"b<="11110111"count<=count+1;elsif(count=N*3/4 thena<="11101111"b<="11111011"count<=count+1;elsif(count=7*N/8 t

18、hena<="11101011"b<="11111101"count<=count+1;elsif(count=Nthena<="11100011"b<="11111110"count<=0;elsecount<=count+1;end if;-m=4顯示“子”,時長為一秒 elsif m=4 thenif(count=N/8 thena<="11111111"b<="01111111"count<=count+1;

19、elsif(count=N/4 thena<="11100011"b<="10111111"count<=count+1;elsif(count=3*N/8 thena<="11111011"b<="11011111"count<=count+1;elsif(count=N/2thena<="11000001"b<="11101111"count<=count+1;elsif(count=N*5/8 thena<=&

20、quot;11110111"b<="11110111"count<=count+1;elsif(count=N*3/4 thena<="11110111"b<="11111011"count<=count+1;elsif(count=7*N/8 thena<="11100111"b<="11111101"count<=count+1;elsif(count=Nthena<="11110111"b<=&quo

21、t;11111110"count<=0;elsecount<=count+1;end if;-m=5顯示“技”,時長為一秒elsif m=5 thenif(count=N/8 thena<="11111111"b<="01111111"count<=count+1;elsif(count=N/4 thena<="11011011"b<="10111111"count<=count+1;elsif(count=3*N/8 thena<="100

22、00001"b<="11011111"count<=count+1;elsif(count=N/2thena<="11000001"b<="11101111"count<=count+1;elsif(count=N*5/8 thena<="11010101"b<="11110111"count<=count+1;elsif(count=N*3/4 thena<="10011111"b<="1111

23、1011"count<=count+1;elsif(count=7*N/8 thena<="10011011"b<="11111101"count<=count+1;elsif(count=Nthena<="11010101"b<="11111110"count<=0;elsecount<=count+1;end if;-m=6顯示“術”,時長為一秒elsif m=6 thenif(count=N/8 thena<="11111111&quo

24、t;b<="01111111"count<=count+1;elsif(count=N/4 thena<="11110011"b<="10111111"count<=count+1;elsif(count=3*N/8 thena<="11000001"b<="11011111"count<=count+1;elsif(count=N/2thena<="11110111"b<="11101111"count<=count+1;elsif(count=N*5/8 thena<="11100011"b<="11110111"count<