alarm_set.vhd

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----libray and package declaraction
library IEEE;
use IEEE.std_logic_1164.all;
use IEEE.std_logic_arith.all;
use IEEE.std_logic_unsigned.all;
Entity alarm_set is
  Port(rst,hz1: in std_logic;--system clock 1Hz
       alarm,ok: in std_logic;--keep pushing to declare alarm set
       sec_tune: in std_logic;-- keep pushing to declare second tuning
       min_tune: in std_logic;-- keep pushing to declare minute tuning
       hour_tune: in std_logic; --keep pushing to declare hour tuning
       sec,min: out integer range 0 to 59;
       hour: out integer range 0 to 23);
End;
----define the signal_structure and _flow of the device 
architecture arch of alarm_set is
  signal sec_tmp,min_tmp:  integer range 0 to 59;
  signal hour_tmp:  integer range 0 to 23;   
begin
  tuning:process(rst,hz1,alarm,ok)
  begin
  if rst='1' then sec_tmp<=0; min_tmp<=0; hour_tmp<=0;
  elsif rising_edge(hz1) then
      if alarm='1' and ok='0' then
           if sec_tune='1' then 
              if sec_tmp=59 then sec_tmp<=0;
                          else sec_tmp<=sec_tmp + 1;
              end if;
           end if;
           if min_tune='1' then 
              if min_tmp=59 then min_tmp<=0;
                          else min_tmp<=min_tmp + 1;
              end if;
           end if;
           if hour_tune='1' then
              if hour_tmp=23 then hour_tmp<=0;
                           else hour_tmp<=hour_tmp + 1;
              end if;
           end if;
      else
          null;
      end if;
  end if;
  end process tuning;
    sec<=sec_tmp;
    min<=min_tmp;
    hour<=hour_tmp;
end arch;