count24.vhd

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Library IEEE;
Use IEEE.std_logic_1164.all;
Use ieee.std_logic_unsigned.all;
Use IEEE.std_logic_arith.all;
Entity count24 is
  Port(carry: in std_logic;--from 1Hz input clock or the full_index of second/minute
         Rst: in std_logic;--initialization
       times: out integer range 0 to 23;
        full: out std_logic);-- carry_out signal
end count24;
architecture arch of count24 is
--input:rst,carry
--output:times,full
  signal time : integer range 0 to 23;
begin
----process for 60 seconds counting
  process (rst,carry)
  begin
    if rst='1' then time <= 0; full<='0';
    elsif rising_edge(carry) then
          if time=23 then time<=0;--over 24
                          full<='1';--carry_out signal
                     else time<= time + 1;--keep counting 
                          full<='0';
          end if;     
    end if;
  end process;
  times<=time;
end arch;