---------------------------------------------------------------------------------------------------
--
-- Title       : mini_vending_machine
-- Design      : mini_vending_machine
-- Author      : Jamie Byun
-- Company     : JMJS
--
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--
-- File        : mini_vending_machine.vhd
-- Generated   : Tue Dec  3 13:13:56 2002
-- From        : interface description file
-- By          : Itf2Vhdl ver. 1.20
--
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--
-- Description : 
--
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--{{ Section below this comment is automatically maintained
--   and may be overwritten
--{entity {mini_vending_machine} architecture {JMJS_Logic}}

library IEEE;
use IEEE.STD_LOGIC_1164.all;
use IEEE.STD_LOGIC_unsigned.all;

entity mini_vending_machine is
	port(
		rst : in STD_LOGIC;
		clk : in STD_LOGIC;
		coffee_button : in STD_LOGIC;
		orange_button : in STD_LOGIC;
		tea_button : in STD_LOGIC;
		change_return : in STD_LOGIC;
		coin_500 : in STD_LOGIC;
		coin_100 : in STD_LOGIC;
		coin_50  : in STD_LOGIC;
		coin_10  : in STD_LOGIC;
		change   : out STD_LOGIC_VECTOR(7 downto 0);
		coffee_out : out STD_LOGIC;
		tea_out : out STD_LOGIC;
		orange_out : out STD_LOGIC
		);
end mini_vending_machine;

--}} End of automatically maintained section

architecture JMJS_Logic of mini_vending_machine is
	signal sum : std_logic_vector(7 downto 0);
begin
	
	process(clk)
	begin
		if (rst = '1') then
			sum <= "00000000";
			orange_out <= '0';
			tea_out <= '0';
			coffee_out <= '0';
		elsif (clk'event and clk='1') then
			if (coin_500 = '1' ) then
				sum <= sum + 50;
				orange_out <= '0';
				tea_out <= '0';
				coffee_out <= '0';
			elsif (coin_100 = '1') then
				sum <= sum + 10;
				orange_out <= '0';
			        tea_out <= '0';
			        coffee_out <= '0';
			elsif (coin_50 = '1') then
				sum <= sum + 5;
				orange_out <= '0';
				tea_out <= '0';
				coffee_out <= '0';
			elsif (coin_10 = '1') then
				sum <= sum + 1;
				orange_out <= '0';
				tea_out <= '0';
				coffee_out <= '0';
			elsif (change_return = '1') then
				sum <= "00000000";
				orange_out <= '0';
				tea_out <= '0';
				coffee_out <= '0';
			elsif (coffee_button = '1' and sum >= 30) then
				sum <= sum - 30;
				coffee_out <= '1';
				tea_out <= '0';
				orange_out <= '0'; 
			elsif (tea_button='1' and sum >= 15) then
				sum <= sum - 15;
				coffee_out <= '0';
				tea_out <= '1';
				orange_out <= '0';
			elsif (orange_button = '1' and sum >= 10) then
				sum <= sum - 10;
				coffee_out <= '0';
				tea_out <= '0';
				orange_out <= '1';
			else
				coffee_out <= '0';
				tea_out <= '0';
				orange_out <= '0';
			end if;
		end if;
	end process;

	process(clk)
	begin
		if (clk'event and clk='1') then
			if (change_return = '1') then
				change <= sum;
			else
				change <= (others => '0');
			end if;
		end if;
	end process;
end JMJS_Logic;