-- Program for Digital Clock with Alarm    

library IEEE;
use IEEE.STD_LOGIC_1164.all;
use IEEE.STD_LOGIC_UNSIGNED.all;
use IEEE.NUMERIC_STD.all;

entity digital_clock is
                    port (
                                clk_1sec: in STD_LOGIC;
                                reset: in STD_LOGIC;
                                load_time: in STD_LOGIC;
                                set_hours: in integer range 0 to 11;
                                set_min: in integer range 0 to 59;
                                set_sec: in integer range 0 to 59;
                                set_am_pm: in STD_LOGIC;
                                load_alarm: in STD_LOGIC;
                                a_hrs_in: in integer range 0 to 11;
                                a_min_in: in integer range 0 to 59;
                                a_am_pm: in STD_LOGIC;
                                alarm_en: in STD_LOGIC;
                                hours: out integer range 0 to 11;
                                min: out integer range 0 to 59;
                                sec: out integer range 0 to 59;
                                am_pm: out STD_LOGIC;
                                flashing: out STD_LOGIC;
                                alarm: out STD_LOGIC
                                    );
end digital_clock;

architecture digital_clock_arch of digital_clock is
signal hours_s: integer range 0 to 11;
signal min_s,sec_s:integer range 0 to 59;
signal am_pm_s:STD_LOGIC;
signal flashing_s:STD_LOGIC;
signal al_hrs : integer range 0 to 11;
signal al_min : integer range 0 to 59;
signal al_am_pm : std_logic;

begin
-- <<enter your statements here>>
process(clk_1sec)
    begin
        if clk_1sec='1' and clk_1sec'event then
            if reset='1'then
                     hours_s<=(0);
                     min_s<=(0);
                     sec_s<=(0);
                     am_pm_s<='0';
                     flashing_s<='1';
            elsif load_time='1' then 
                     hours_s<=set_hours;
                     min_s<=set_min;
                     sec_s<=set_sec;
                     am_pm_s<=set_am_pm;
                     flashing_s<='0'; 
            else
                     flashing_s<= not flashing_s;
                             if sec_s = 59 then 
                                 sec_s<=(0);
                                 if min_s = 59 then
                                     min_s<=(0);
                                     if hours_s = 11 then
                                         hours_s<=(0);
                                         am_pm_s<=not am_pm_s;
                                     else
                                         hours_s<=hours_s + 1;
                                         am_pm_s<= am_pm_s;
                                     end if;
                                 else
                                     min_s<=min_s+ 1 ;
                                     hours_s<=hours_s;
                                     am_pm_s<= am_pm_s;
                                 end if;
                         else 
                                     sec_s<=sec_s + 1;
                                     min_s<=min_s;
                                     hours_s<=hours_s;
                                     am_pm_s<= am_pm_s;
                         end if;
            end if;
        end if;
    end process;                             
hours<=hours_s;                             
min<=min_s;
sec<=sec_s;
am_pm<=am_pm_s;
flashing <= flashing_s;

--
process(clk_1sec)
        begin
            if clk_1sec='1' and clk_1sec'event then
                if reset='1' then
                    al_hrs <= 0;
                    al_min <= 0;
                    al_am_pm <= '0';
                elsif load_alarm='1' then
                    al_hrs <= a_hrs_in;
                    al_min <= a_min_in;
                    al_am_pm <= a_am_pm;
                else
                    al_hrs <= al_hrs;
                    al_min <= al_min;
                    al_am_pm <= al_am_pm;
                end if;
            end if;
            
            if (min_s = al_min and hours_s=al_hrs) and (am_pm_s=al_am_pm and alarm_en='1') then
                alarm <= '1';
            else
                alarm <= '0';
            end if;
    end process;
end digital_clock_arch;