sellm.vhd

vhdl实现的自动售货机 实现了售货

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-- Company: 
-- Engineer: 
-- 
-- Create Date:    18:19:33 10/24/2007 
-- Design Name: 
-- Module Name:    sellm - Behavioral 
-- Project Name: 
-- Target Devices: 
-- Tool versions: 
-- Description: 
--
-- Dependencies: 
--
-- Revision: 
-- Revision 0.01 - File Created
-- Additional Comments: 
--
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library IEEE;
use IEEE.STD_LOGIC_1164.ALL;
use IEEE.STD_LOGIC_ARITH.ALL;
use IEEE.STD_LOGIC_UNSIGNED.ALL;

---- Uncomment the following library declaration if instantiating
---- any Xilinx primitives in this code.
--library UNISIM;
--use UNISIM.VComponents.all;

entity sellm is
port(
	CLK, RST: in std_logic;
	C100, C50, C10: in std_logic;
	SEL1, SEL2: in std_logic;
	Return_Coins: in std_logic;
	Dispense_item1: out std_logic;
	Dispense_item2: out std_logic;
	Collect_coins: out std_logic;
	R_C100, R_C50, R_C10: out std_logic;
	No_return_coins: out std_logic;
	Lock_out_entry: out std_logic
);
end sellm;

architecture Behavioral of sellm is
	signal C100_b, C50_b, C10_b: std_logic;
	signal C100_p, C50_p, C10_p: std_logic;
	signal SEL1_b, SEL2_b: std_logic;
	signal SEL1_p, SEL2_p: std_logic;
	signal Return_coins_b: std_logic;
	signal Return_coins_p: std_logic;
	signal N100, N50, N10: integer;   -- number of coins in the machine
	signal Sum,rest: integer;
	signal Dispense_item1_b: std_logic:='0';
	signal Dispense_item2_b: std_logic:='0';
	signal Collect_coins_b: std_logic:='0';
	signal R_C100_b, R_C50_b, R_C10_b: std_logic:='0';
	signal No_return_coins_b: std_logic:='0';
	signal Lock_out_entry_b: std_logic:='0';
	signal done :std_logic:='0';
	signal rejecto :std_logic:='0';
	signal I :std_logic:='0';
--calculate A Divided by B
	function Division(A, B: integer) return integer is
		variable r: integer;
		variable c,d: integer; 
	begin
	    r:=0;
	    c:=A;
	    d:=B;
   while c-d>=0 loop
				c:= c-d;
				r := r+1;
		end loop;
		return r;
	end Division;
	
-- judge whether appropriate change could be give	
	function echange(Sum, N100, N50, N10, price: in integer) return std_logic is
		variable Loop_1, Loop_2: integer;
	begin
		if Division((Sum-price),10) > N100 then
			Loop_1 := N100;
		else 
			Loop_1 := Division((Sum-price),10);
		end if;
		if Division((Sum-10*Loop_1-price),5) > N50 then
			Loop_2 := N50;
		else
			Loop_2 := Division((Sum-10*Loop_1-price),5);
		end if;
		if (Sum-price-Loop_1*10-Loop_2*5 > N10) then
			return '0';
		else
			return '1';
		end if;
	end echange;
		
begin

Dispense_item1 <= Dispense_item1_b;
Dispense_item2 <= Dispense_item2_b;
Collect_coins <= Collect_coins_b;
R_C100 <= R_C100_b;
R_C50 <= R_C50_b;
R_C10 <= R_C10_b;
No_return_coins <= No_return_coins_b;
Lock_out_entry <= Lock_out_entry_b;

Detectpro: process(clk) -- generate the pulse
begin
	if CLK'event and CLK = '1'then
	   if Lock_out_entry_b<='0' then
		   if rejecto ='0' then 
		      C100_b <= C100;
		      C50_b <= C50;
		      C10_b <= C10;
		      SEL1_b <= SEL1;
		      SEL2_b <= SEL2;
		      C100_p <= C100 and (not C100_b);
            C50_p <= C50 and (not C50_b);
            C10_p <= C10 and (not C10_b);
            SEL1_p <= SEL1 and (not SEL1_b);
            SEL2_p <= SEL2 and (not SEL2_b);
		    else
		      C100_b <= '0';
            C50_b <= '0';
            C10_b <= '0';
            SEL1_b <= '0';
            SEL2_b <= '0';
    		      C100_p <= '0';
            C50_p <= '0';
            C10_p <= '0';
            SEL1_p <= '0';
            SEL2_p <= '0';
          end if;
  		    Return_coins_b<= Return_coins;
  		    Return_coins_p <= Return_coins and (not Return_coins_b);  		 
  		    else
  		    Return_coins_b<= '0';
  		    Return_coins_p<= '0';
  		 end if;  
  	
      
   end if;
end process Detectpro;



coinpro: process(CLK, RST)
begin
	if RST = '1' then
		N100 <= 10; N50 <= 10; N10 <= 10;
		Sum <= 0;
	else
	   if CLK'event and CLK = '1' then
		if C100_p = '1' then
			N100 <= N100+1;
			Sum <= Sum+10;
		elsif C50_p = '1' then
			N50 <= N50+1;
			Sum <= Sum+5;
		elsif C10_p ='1' then
			N10 <= N10+1;
			Sum <= Sum+1;
		elsif R_C100_b = '1' then
			N100 <= N100-1;
		elsif R_C50_b = '1' then
			N50 <= N50-1;
		elsif R_C10_b = '1' then
			N10 <= N10-1;
		elsif Return_coins_p = '1' then
			Sum <= 0;
		end if;
		end if;
	end if;
end process coinpro;

Itempro: process(CLK,RST)
begin
   if CLK'event and CLK = '1' then
			Collect_coins_b <= '0';
			No_return_coins_b <= '0';
			Dispense_item1_b <= '0';
			Dispense_item2_b <= '0';
			if SEL1_p = '1' then
			   rejecto<='1';
			   if Sum < 18 then 		
				elsif echange(Sum, N100, N50, N10, 18)='1' then
				   Collect_coins_b <= '1';
					Dispense_item1_b <= '1';
					rest <= Sum-18;
					i<='1';
				  else
					No_return_coins_b <= '1';
				end if;
			elsif SEL2_p = '1' then
			    rejecto<='1';
			   if Sum < 12 then 	
				elsif echange(Sum, N100, N50, N10, 12) = '1' then
					Collect_coins_b <= '1';
					Dispense_item2_b <= '1';
					rest <= Sum-12;
					i<='1';
				else 
					No_return_coins_b <= '1';
				end if;
			elsif Return_coins_p = '1' then
				Collect_coins_b <= '1';
				Lock_out_entry_b<='1';
				if i='0' then
				rest<=sum;
				else 
            i<='0';
				end if;
				elsif done='1'then
			   Lock_out_entry_b<='0';
			   rejecto<='0';
			   rest<=0;
			end if;
		end if;
end process itempro;

Changepro: process
	variable N100_v, N50_v, N10_v, I100_v, I50_v, I10_v, Sum_v: integer;
   variable Loop_1, Loop_2, Loop_3: integer;
begin
	wait until CLK'event and CLK = '1' and Return_coins_p = '1';
	wait until CLK'event and CLK = '1';
	wait until CLK'event and CLK = '1'; 
	N100_v := N100; N50_v := N50; N10_v := N10;
	Sum_v := rest;
	if Division(Sum_v,10) > N100 then
		Loop_1 := N100;
	else
		Loop_1 := Division(Sum_v,10);
	end if;
	if Division((Sum_v-10*Loop_1),5) > N50 then
		Loop_2 := N50;
	else
		Loop_2 := Division((Sum_v-10*Loop_1),5);
	end if;
	Loop_3 := Sum_v-10*Loop_1-5*Loop_2;
   while Loop_1>0 loop
       Loop_1:=Loop_1-1;
		wait until CLK'event and CLK = '1';
		R_C100_b <= '1';
		wait until CLK'event and CLK = '1';
		R_C100_b <= '0';
	end loop;
	while Loop_2>0 loop
		Loop_2:= Loop_2 -1;
      wait until CLK'event and CLK = '1';
		R_C50_b <= '1';
		wait until CLK'event and CLK = '1';
		R_C50_b <= '0';
	end loop;
   while Loop_3>0 loop
      Loop_3:=Loop_3-1;
		wait until CLK'event and CLK = '1';
		R_C10_b <= '1';
		wait until CLK'event and CLK = '1';
		R_C10_b <= '0';
	end loop;
	   wait until CLK'event and CLK = '1';
  done<='1';
  wait until CLK'event and CLK='1';
  done<='0';
end process changepro;

end Behavioral;