----------------------------------------------------------------------------------
    -- Company:  INSA-Toulouse
    -- Engineer: Paul Faure
    -- 
		-- Create Date: 05.07.2021 15:20:28
		-- Module Name: Compteur_X - Behavioral
		-- Project Name: Processeur sécurisé
    -- Target Devices: Basys 3 ARTIX7
    -- Tool Versions: Vivado 2016.4
    -- Description: Compteur la coordonnée X du VGA
    -- 
    -- Dependencies: 
    --    - None
    ----------------------------------------------------------------------------------


library IEEE;
use IEEE.STD_LOGIC_1164.ALL;

use work.ScreenProperties.all;

entity Compteur_X is
    Port ( CLK : in STD_LOGIC;
           RST : in STD_LOGIC;
           Value : out X_T;
           Carry : out STD_LOGIC);
end Compteur_X;

architecture Behavioral of Compteur_X is

signal current : X_T := 0;
signal intern_Carry : STD_LOGIC := '0';
    
begin

    process
    begin
        wait until CLK'event and CLK = '1';
        if (RST = '0') then
            current <= 0;
        else 
            current <= current + 1;
            if (current = screen_width + X_PulseWidth + X_FrontPorch + X_BackPorch - 1) then
                intern_Carry <= '1'; 
                current <= 0;
            else 
                intern_Carry <= '0';
            end if;
        end if;
    end process;
    
    Value <= current;
    Carry <= intern_Carry;
    
end Behavioral;