rel_clock.vhd

数字钟的程序

library ieee;
use ieee.std_logic_1164.all; 
use ieee.std_logic_unsigned.all;
entity shuzizhong is
  port(clk,set,change,s1,s2,s3:in std_logic;
       second1,second2,minite1,minite2,hour1,hour2:out std_logic_vector(3 downto 0);
      cout:out std_logic);
end entity;
architecture one of shuzizhong is
begin 
  pro1:process(clk,set,s1,s2,s3,change)
 variable msecond1,msecond2,mminite1,mminite2,mhour11,mhour12,mhour21,mhour22:std_logic_vector(3 downto 0);
 begin 
     if clk'event and clk='1' then

     if set='1' then     -----启动校验
        if s1='1'  
         then msecond1:=msecond1+1;
            if msecond1="1010"
              then msecond1:="0000";
                  msecond2:=msecond2+1;
                   if msecond2="0110"
                 then msecond2:="0000";
               end if;
           end if;
           end if;    --------秒校验
         if s2='1'
     then 
       mminite1:=mminite1+1;
                     if mminite1="1010"
                        then mminite1:="0000";
                             mminite2:=mminite2+1;
                            if mminite2="0110" 
                               then mminite2:="0000";
                        end if;
                     end if;
                  end if;     ---------分校验
       if s3='1' then 
                   mhour11:=mhour11+1;
                   mhour21:=mhour21+1;
                   if mhour11="1010" then mhour11:="0000";
                       mhour12:=mhour12+1;
                   end if;
                         if mhour11="0011" and mhour12="0001"
                            then mhour11:="0001";mhour12:="0000";
                             end if;
                          if mhour21="1010" then mhour21:="0000";
                              mhour22:=mhour22+1;
                              end if;
                              if mhour21="0100"and mhour22="0010"
                              then mhour21:="0000";mhour22:="0000";
                     end if;
     
     end if;-------时校验
   else  msecond1:=msecond1+1;-----正常计时工作
      if msecond1="1010"
        then msecond1:="0000";
             msecond2:=msecond2+1;
            if msecond2="0110"
                 then msecond2:="0000";
                      mminite1:=mminite1+1;
                     if mminite1="1010"
                        then mminite1:="0000";
                             mminite2:=mminite2+1;
                            if mminite2="0110" 
                               then mminite2:="0000";
                                    mhour11:=mhour11+1;
                                    mhour21:=mhour21+1;
                                    if mhour11="1010" then mhour11:="0000";
                                                           mhour12:=mhour12+1;
                                                              end if;
                                                          if mhour11="0011" and mhour12="0001"
                                                              then mhour11:="0001";mhour12:="0000";
                                                              end if;-------12小时制
                                    if mhour21="1010" then mhour21:="0000";
                                                           mhour22:=mhour22+1;
                                                          end if;
                                                         if mhour21="0100"and mhour22="0010"
                                                              then mhour21:="0000";mhour22:="0000";
                                                           end if;----------24小时制
                                                                                                  
                                    
end if;
end if;
end if;
end if;

if (msecond1="0000") and (msecond2="0000") and (mminite1="0000") and (mminite2="0000")
            then cout<='1';
              else cout<='0';
             end if;-----------整点报时

end if;
end if;
second1<=msecond1;
second2<=msecond2;
minite1<=mminite1;
minite2<=mminite2;
if change='0' then hour1<=mhour11;hour2<=mhour12;  
else hour1<=mhour21;hour2<=mhour22;------12/24小时制转换
end if;

end process;

end architecture one;