----libray and package declaraction
library IEEE;
use IEEE.std_logic_1164.all;
use IEEE.std_logic_arith.all;
use IEEE.std_logic_unsigned.all;
use work.my_pkg.all;
Entity clock is
  Port(rst: in std_logic;--power reset to initialize 
       clk: in std_logic;--system clock 1024Hz
     alarm: in std_logic;--dip switch for alarm setting
      stop: in std_logic;--dip switch for stop watch setting
        Ok: in std_logic;--push button to confirrn any setting operation       
  Sec_tune: in std_logic;--pushing button to tune seconds
  Min_tune: in std_logic;--pushing button to tune minutes
 Hour_tune: in std_logic;--pushing button to tune hourss
 led_alarm: out std_logic;--led to show alarm time reached
  led_stop: out std_logic;--led to show count_down over 
      seg4: out std_logic_vector(6 downto 0);--display seconds and minutes      
     p1,p2,p3,p4: out std_logic;--power for sec_one,sec_ten,min_one and min_ten
      seg2: out std_logic_vector(6 downto 0);--display hours      
      p5,p6: out std_logic);--power for hour_one,hour_ten
End clock;

architecture arch of clock is
--global signals flowing among different circuit blocks
  signal Hz1:std_logic;--1 Hz clock
--normal dispay time
  signal n_sec,n_min: integer range 0 to 59;
  signal n_hour: integer range 0 to 23;
--alarm display time
  signal a_sec,a_min: integer range 0 to 59;
  signal a_hour: integer range 0 to 23;
--stop display time
  signal s_sec,s_min: integer range 0 to 59;
  signal s_hour: integer range 0 to 23;
--chosen display time
  signal second,minute :integer range 0 to 59;
  signal hour :integer range 0 to 23;  
  signal sec_one,sec_ten,min_one,min_ten: std_logic_vector(3 downto 0);
  signal hour_one,hour_ten: std_logic_vector(3 downto 0);
--chosen display time in 7-segments led format
  signal sec7_one,sec7_ten,min7_one,min7_ten: std_logic_vector(6 downto 0);
  signal hour7_one,hour7_ten: std_logic_vector(6 downto 0);
--index for alarm or stop_watch status
  signal stop_index,alarm_index: std_logic;  
  signal alarm_disp,stop_disp : std_logic;
begin

----normal counting from 00:00:00 to 23:59:59
normal_counting:Block
--input : rst,clk
--output: Hz1, n_sec,n_min,n_hour    
  signal full_sec:std_logic;--index of 60 seconds fully counted
  signal full_min:std_logic;--index of 60 minutes fully counted
  signal full_hour:std_logic;--index of 24 hours fully counted
begin
--to get 1Hz clock
  u0:div1024   port map(clk=>clk,f1hz=>Hz1);
--to count from 0 to 60 seconds and get full_sec
  u1:count60 port map(rst=>rst,carry=>hz1,times=>n_sec,full=>full_sec);
--to count from 0 to 60 minutes and get full_min
  u2:count60 port map(rst=>rst,carry=>full_sec,times=>n_min,full=>full_min);
--to count from 0 to 24 hours and get full_hour
  u3:count24 port map(rst=>rst,carry=>full_min,times=>n_hour,full=>full_hour);
end block normal_counting;

----stop watch setting and down_counting
stop_w: block
--input:rst,hz1,stop,ok,sec_tune,min_tune,hour_tune
--output:s_sec,s_min,s_hour,stop_index
begin
u4:stop_watch port MAP(rst=>rst,hz1=>hz1,stop=>stop,ok=>ok,sec_tune=>sec_tune,
                      min_tune=>min_tune,hour_tune=>hour_tune,stop_sec=>s_sec,
                 stop_min=>s_min,stop_hour=>s_hour,index=>stop_index,disp=>stop_disp);     
  p1:process(rst,stop_index)
  begin
    if rst='1' then led_stop<='0';
    elsif rising_edge(stop_index) then
          led_stop<='1';  
    end if;
  end process p1;
  
end block stop_w;

alarm_setting:Block
--input : rst,sec_tune,min_tune,hour_tune,alarm,ok
--output: a_sec,a_min,a_hour,alarm_index,led_alarm    
begin
  u5:alarm_set port map(rst=>rst,hz1=>hz1,alarm=>alarm,ok=>ok,sec_tune=>sec_tune,
                       min_tune=>min_tune,hour_tune=>hour_tune,
                       sec=>a_sec,min=>a_min,hour=>a_hour);
  p1:process(alarm,ok)
  begin
    if rst='1' then alarm_index<='0';
    elsif alarm='1' and ok='1' then
          if (a_sec=n_sec and a_min=n_min and a_hour=n_hour)
                      then alarm_index<='1';
                      else alarm_index<='0';
          end if;
    end if;
  alarm_disp<=(alarm and not ok) and not alarm_index; 
  end process p1;
  p2:process(rst,alarm_index)
  begin
    if rst='1' then led_alarm<='0';
    elsif rising_edge(alarm_index) then
          led_alarm<='1';  
    end if;
  end process p2;
   
end block alarm_setting;

----to decide which time displayed and transform to BCD format
output:block
--input:clk,stop_disp,alarm_disp
--input:s_sec,s_min,s_hour,a_sec,a_min,a_hour,n_sec,n_min,n_hour
--output:second,minute,hour
begin
  process(clk,stop_disp,alarm_disp)
  begin
  if rising_edge(clk) then
    if stop_disp='1' then second<=s_sec;
                          minute<=s_min;
                            hour<=s_hour;
    elsif alarm_disp='1' then second<=a_sec;
                              minute<=a_min;
                                hour<=a_hour;                  
                         else second<=n_sec;
                              minute<=n_min;
                                hour<=n_hour;   
    end if;
  end if;  
  end process;           
----tranformed to BCD format
  u6:i60bcd port MAP(interg=>second,ten=>sec_ten,one=>sec_one);
  u7:i60bcd port MAP(interg=>minute,ten=>min_ten,one=>min_one);  
  u8:i24bcd port MAP(interg=>hour,ten=>hour_ten,one=>hour_one);  
end block output;

---transform BCD format to 7_segment LED display format and scan out
scan_display:block
begin
  u11:bin2led port map(bin=>sec_one,led=>sec7_one);   
  u12:bin2led port map(bin=>sec_ten,led=>sec7_ten);   
  u13:bin2led port map(bin=>min_one,led=>min7_one);   
  u14:bin2led port map(bin=>min_ten,led=>min7_ten);   
  u15:bin2led port map(bin=>hour_one,led=>hour7_one);   
  u16:bin2led port map(bin=>hour_ten,led=>hour7_ten);
  u17:scan4  port map(rst=>rst,clk=>clk,
                       a=>sec7_one,b=>sec7_ten,c=>min7_one,d=>min7_ten,    
                       mux_out=>seg4,pa=>p1,pb=>p2,pc=>p3,pd=>p4);
  u18: scan2  port map(rst=>rst,clk=>clk,
                       a=>hour7_one,b=>hour7_ten,mux_out=>seg2,pa=>p5,pb=>p6);
end block scan_display;
  
end arch;