counter60.vhd

该实验设计模60计数器

library IEEE;
use IEEE.STD_LOGIC_1164.all;
use ieee.std_logic_unsigned.all;
entity counter60 is
	 port(
		 clk : in STD_LOGIC;
		 rst : in STD_LOGIC;
		 en : in STD_LOGIC;
		 led7s0,led7s1 : out STD_LOGIC_VECTOR(6 downto 0)
	     );
end counter60;
architecture counter60 of counter60 is
signal q_tmp:STD_LOGIC_VECTOR(7 downto 0);
signal q_bcd_low,q_bcd_high:STD_LOGIC_VECTOR(3 downto 0);
signal q_bcd :STD_LOGIC_VECTOR(7 downto 0);
begin
	process(clk,rst)
	begin
		if rst='1' then 
		q_tmp<=(others=>'0');	
		elsif clk'event and clk='1' then
			if en='1' then
				if q_tmp=59 then
				  q_tmp<=(others=>'0');
				else
			      q_tmp<=q_tmp+1;
				end if;
			end if;
		end if;
		end process;
q_bcd_low<=q_bcd(3 downto 0);
q_bcd_high<=q_bcd(7 downto 4);
P1: process(q_tmp)
begin
	if q_tmp<=9 then
		q_bcd<=q_tmp;
	elsif q_tmp<=19 then
		q_bcd<=q_tmp+6;
	elsif q_tmp<=29 then
		q_bcd<=q_tmp+12;
	elsif q_tmp<=39 then
		q_bcd<=q_tmp+18;
	elsif q_tmp<=49 then
		q_bcd<=q_tmp+24;
	elsif q_tmp<=59 then
		q_bcd<=q_tmp+30;
	else
		q_bcd<=q_tmp;
	end if;
end process;
P2: process(q_bcd_low)
begin
	case q_bcd_low  is
		when "0000" =>led7s0<="0111111";
		when "0001" =>led7s0<="0000110";
		when "0010" =>led7s0<="1011011";
		when "0011" =>led7s0<="1001111";
		when "0100" =>led7s0<="1100110";
		when "0101" =>led7s0<="1101101";
		when "0110" =>led7s0<="1111101";
		when "0111" =>led7s0<="0000111";
		when "1000" =>led7s0<="1111111";
		when "1001" =>led7s0<="1101111";
		when "1010" =>led7s0<="1110111";
		when "1011" =>led7s0<="1111100";
		when "1100" =>led7s0<="0111001";
		when "1101" =>led7s0<="1011110";
		when "1110" =>led7s0<="1111001";
		when "1111" =>led7s0<="1110001";
		end case;
end process;
P3: process(q_bcd_high)
begin
	case q_bcd_high  is
		when "0000" =>led7s1<="0111111";
		when "0001" =>led7s1<="0000110";
		when "0010" =>led7s1<="1011011";
		when "0011" =>led7s1<="1001111";
		when "0100" =>led7s1<="1100110";
		when "0101" =>led7s1<="1101101";
		when "0110" =>led7s1<="1111101";
		when "0111" =>led7s1<="0000111";
		when "1000" =>led7s1<="1111111";
		when "1001" =>led7s1<="1101111";
		when "1010" =>led7s1<="1110111";
		when "1011" =>led7s1<="1111100";
		when "1100" =>led7s1<="0111001";
		when "1101" =>led7s1<="1011110";
		when "1110" =>led7s1<="1111001";
		when "1111" =>led7s1<="1110001";
		end case;
end process;
end counter60;