washer_statement.vhd

用VHDL编的洗衣机程序

library ieee;
use ieee.std_logic_1164.all;
use ieee.std_logic_unsigned.all;
entity washer_statement is
	port(
		 s_and_p,clk50,nextsta_w,power_w: in std_logic;
		 pause_w: out std_logic;
		 statectrl: in std_logic_vector(2 downto 0);
		 count_w: out std_logic_vector(5 downto 0)
		);
end washer_statement;

architecture washer_statement_1 of washer_statement is
type state_type is (ready,wash1,wash2,wash3,wash4);
signal present_state,next_state: state_type;
signal s: std_logic;

 begin 
	process(present_state)
	begin
		case present_state is
		when ready => if statectrl(2)='1' then next_state<=wash1;
					  elsif statectrl(1)='1' then next_state<=wash2;
					  elsif statectrl(0)='1' then next_state<=wash3; 
					  else  next_state<=ready;
					  end if;
		when wash1 => if statectrl(1)='1' then next_state<=wash2;
					  elsif statectrl(0)='1' then next_state<=wash3;
					  else next_state<=wash4;
					  end if;
		when wash2 => if statectrl(0)='1' then next_state<=wash3;
					  else next_state<=wash4;
					  end if;
		when wash3 => next_state<=wash4;
		when wash4 => next_state<=ready;
		when others => next_state<=ready;
		end case;
	end process;
	
	process(clk50,nextsta_w)
	begin 
		--if( clk50'event and clk50='1' )then 
			if (nextsta_w'event and nextsta_w='1') then
				present_state<=next_state;
			end if;
		--end if;
	end process;
	
	process(present_state,s_and_p)
	begin
		case present_state is
		when ready => if(power_w='0')then
						s<='1';
					  else
						if(s_and_p='1')then
							s<='0';
						else
							s<='1';
						end if;
					  end if;
					  count_w<="000000";				  
		when wash1 => if (s_and_p'event and s_and_p='1') then 
						if (s='0') then 
							s<='1';
					    else 
							s<='0';
						end if;
					  end if; 
					  count_w<="010100";
		when wash2 => if (s_and_p'event and s_and_p='1') then 
						if (s='0') then 
							s<='1';
					    else 
							s<='0';
						end if;
					  end if;
					  count_w<="011110";	
		when wash3 => if (s_and_p'event and s_and_p='1') then 
						if (s='0') then 
							s<='1';
					    else 
							s<='0';
						end if;
					  end if;
					  count_w<="001111";
		when wash4 => count_w<="000101";	
		when others => count_w<="000000";	
		end case;
		pause_w<=s;
	end process;
end washer_statement_1;