alarm_controller.vhd

可以调整时间和设置闹钟的数字钟(VHDL)

library ieee;
use ieee.std_logic_1164.all;
use work.p_alarm.all;
entity alarm_controller is
	port(	key: in std_logic;
			alarm_button:	in std_logic;
			time_button :	in std_logic;
			clk			:	in std_logic;
			reset		:	in std_logic;
			load_new_a	:	out std_logic;
			load_new_c	:	out std_logic;
			show_new_time:  out std_logic;
			show_a		:	out std_logic);
end alarm_controller;

architecture art of alarm_controller is
	type t_state is(s0,s1,s2,s3,s4);
	constant key_timeout : t_short:=500;
	constant show_alarm_timeout: t_short:=500;
	
	signal curr_state: t_state;
	signal next_state: t_state;
	
	signal counter_k: t_short;
	signal enable_count_k: std_logic;
	signal count_k_end: std_logic;
	
	signal counter_a: t_short;
	signal enable_count_a: std_logic;
	signal count_a_end: std_logic;
	
	begin
		states: process(clk,reset) is
			begin
					if(reset='1') then
						curr_state<=s0;
					elsif(rising_edge(clk)) then
						curr_state<=next_state;
					end if;
		end process;
		
	    ariths: process(key,alarm_button,time_button,curr_state,count_a_end,count_k_end) is
			begin
				next_state<=curr_state;
				load_new_a<='0';
				load_new_c<='0';
				show_a<='0';
				show_new_time<='0';
				enable_count_k<='0';
				enable_count_a<='0';
				
				case curr_state is
					when s0=>
								if(key='1') then
									next_state<=s1;
									show_new_time<='1';
								elsif(alarm_button='1') then
									next_state<=s4;
									show_a<='1';
								else
									next_state<=s0;
								end if;
					when s1=>
								if(key='1') then
									next_state<=s1;
								elsif(alarm_button='1') then
									next_state<=s2;
									load_new_a<='1';
								elsif(time_button='1') then
									next_state<=s3;
									load_new_c<='1';
								else
									if(count_k_end='1') then
										next_state<=s0;
								    else
										next_state<=s1;
									end if;
									enable_count_k<='1';
								end if;
								show_new_time<='1';
					when s2=>
								if(alarm_button='1') then
									next_state<=s2;
									load_new_a<='1';
								else 
									next_state<=s0;
								end if;
					when s3=>
								if(time_button='1') then
									next_state<=s3;
									load_new_c<='1';
								else 
									next_state<=s0;
								end if;
					when s4=>
								if(key='1') then
									next_state<=s1;
								else 
									next_state<=s4;
									if(count_a_end='1') then
										next_state<=s0;
									else 
										next_state<=s4;
										show_a<='1';
									end if;
									enable_count_a<='1';
								end if;
					when others=>
									null;
									
			end case;
		end process;
		
		count_key: process(enable_count_k,clk) is
					begin
						if(enable_count_k='0') then
							counter_k<=0;
							count_k_end<='0';
						elsif(rising_edge(clk)) then
							if(counter_k>=key_timeout) then
									count_k_end<='1';
							else
									counter_k<=counter_k+1;
							end if;
						end if;
			 end process;
			 
		count_alarm: process (enable_count_a,clk) is
					begin
						if(enable_count_a='0') then
							counter_a<=0;
							count_a_end<='0';
						elsif(rising_edge(clk)) then
							if(counter_a>=show_alarm_timeout) then
									count_a_end<='1';
							else
									counter_a<=counter_a+1;
							end if;
						end if;
					  end process;
	end art;