tingche.vhd

停车场显示是日常生活中使用很平常的系统

--此模块实现车的任意位置停放或离开，并显示剩余车位数量
library ieee;
use ieee.std_logic_1164.all;
use ieee.std_logic_unsigned.all;
use ieee.std_logic_arith.all;

entity tingche is
	port(
		clk    : in std_logic;
		hello  : in std_logic;
		data   : in std_logic_vector(2 downto 0);    --停车位的行/列值选择
		hang    : in std_logic;                      
		lie    : in std_logic;                        
		jin  : in std_logic;                        
		chu : in std_logic;                       
		sel    : in std_logic_vector(2 downto 0);     
		q      : out std_logic_vector(7 downto 0);    
		chewei: out std_logic_vector(6 downto 0);   --停车位数目
		empty     : out std_logic                       --停车场是否为空
		); 
end tingche;

architecture park of tingche is 
	type stop is array(0 to 7) of std_logic_vector(7 downto 0); --8X8数组作为停车位
	begin
			
		process(clk)
		variable tmp:stop;
		variable h,l:std_logic_vector(2 downto 0);
		variable h_num,l_num:integer range 0 to 7;
		variable i,j:integer range 0 to 7;
		variable carnum:integer range 0 to 64;
		variable x:std_logic;
		begin
			carnum:=0;
			if clk'event and clk='1' then
				if x='0' then                 --初始化为停车场为空
					tmp(0):="00000000";
					tmp(1):="00000000";
					tmp(2):="00000000";
					tmp(3):="00000000";
					tmp(4):="00000000";
					tmp(5):="00000000";
					tmp(6):="00000000";
					tmp(7):="00000000";
					x:='1';
				else
					if hang = '1' then                  
						h:=data;
						h_num:=conv_integer(h);
					elsif lie='1' then                
						l:=data;
						l_num:=conv_integer(l);
					elsif jin='1' then             --在相应位置停进一部车，点亮相应灯
						tmp(l_num)(h_num):='1';
					elsif chu='1' then           
						tmp(l_num)(h_num):='0';
					end if;
					case sel is                      --根据列选信号，输出相应列值值
						when "000"=>q<=tmp(0);
						when "001"=>q<=tmp(1);
						when "010"=>q<=tmp(2);
						when "011"=>q<=tmp(3);
						when "100"=>q<=tmp(4);
						when "101"=>q<=tmp(5);
						when "110"=>q<=tmp(6);
						when "111"=>q<=tmp(7);
						when others =>null;
					end case;
				end if;
			end if;
			if hello ='1' then         
				tmp(0):="00000000";
				tmp(1):="00000000";
				tmp(2):="00000000";
				tmp(3):="00000000";
				tmp(4):="00000000";
				tmp(5):="00000000";
				tmp(6):="00000000";
				tmp(7):="00000000";
				h:="000";
				l:="000";
				h_num:=0;
				l_num:=0;
			end if; 
			
			L1:for i in 0 to 7 loop     --记录车数
				L2:for j in 0 to 7 loop
					if(tmp(i)(j)='1')then
						carnum:=carnum+1;
					end if;
				end loop L2;
			end loop L1;
 			
			if(carnum = 0)then
				empty<='1';
			else
				empty<='0';
			end if;
			chewei<=64-conv_std_logic_vector(carnum,7);--输出车位个数
		end process;
			
end park;