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+----------------------------------------------------------------------------------
+-- Company:
+-- Engineer:
+--
+-- Create Date: 22.02.2023 13:20:47
+-- Design Name:
+-- Module Name: ppu_vga_native - Behavioral
+-- Project Name:
+-- Target Devices:
+-- Tool Versions:
+-- Description:
+--
+-- Dependencies:
+--
+-- Revision:
+-- Revision 0.01 - File Created
+-- Additional Comments:
+--
+----------------------------------------------------------------------------------
+
+
+library IEEE;
+use IEEE.STD_LOGIC_1164.ALL;
+use work.ppu_consts.all;
+
+use IEEE.NUMERIC_STD.ALL;
+use IEEE.STD_LOGIC_UNSIGNED.ALL;
+
+-- Uncomment the following library declaration if instantiating
+-- any Xilinx leaf cells in this code.
+--library UNISIM;
+--use UNISIM.VComponents.all;
+
+entity ppu_vga_native is
+ Port ( CLK: in std_logic; -- system clock
+ RESET: in std_logic;
+
+ X: in std_logic_vector(PPU_POS_H_WIDTH-1 downto 0); -- current screen pixel x
+ Y: in std_logic_vector(PPU_POS_V_WIDTH-1 downto 0); -- current screen pixel y
+ PREADY: in std_logic; -- current pixel ready (pixel color is stable)
+ RI,GI,BI: in std_logic_vector(PPU_COLOR_OUTPUT_DEPTH-1 downto 0); -- VGA color in
+
+ RO,GO,BO: out std_logic_vector(PPU_COLOR_OUTPUT_DEPTH-1 downto 0); -- VGA color out
+ VSYNC, HSYNC: out std_logic); -- VGA sync outputs
+end ppu_vga_native;
+
+architecture Behavioral of ppu_vga_native is
+ type line_buffer is array(319 downto 0) of std_logic_vector(11 downto 0);
+ signal ram_x0 : line_buffer; -- buffer 0
+ signal ram_x1: line_buffer; -- buffer 1
+ signal hcount: STD_LOGIC_VECTOR(9 downto 0):= (others => '0');
+ signal vcount: STD_LOGIC_VECTOR(9 downto 0):= (others => '0');
+ signal rgb_out : STD_LOGIC_VECTOR(11 downto 0):= (others => '0'); -- output colors
+ signal px : integer; -- conversion for hcount
+ signal py :integer; -- conversion for vcount
+ signal bufferFilledOnbuffer0 : integer;
+ signal bufferFilledOnbuffer1 :integer;
+begin
+ process (clk, x, y)
+ variable v_x : integer ; -- integer to hold vector X
+ begin
+ if rising_edge(clk) then
+
+ v_x := TO_INTEGER(unsigned(x) - 72);
+ if(v_x >= 0 and v_x < 320 and PREADY = '1') then
+ if(y(0) = '0') then
+ ram_x0(v_x) <= RI & GI & BI;
+ if v_x = 319 then
+ bufferFilledOnbuffer0 <= TO_INTEGER(unsigned(y) - 14);
+ end if;
+ else
+ ram_x1(v_x) <= RI & GI & BI;
+ if v_x = 319 then
+ bufferFilledOnbuffer1 <= TO_INTEGER(unsigned(y) - 14);
+ end if;
+ end if;
+ end if;
+ -- T display(display data)
+ if (hcount >= 144) and (hcount < 784) and (vcount >= 31) and (vcount < 511) then
+ px <= TO_INTEGER(unsigned(hcount) - 144);
+ py <= TO_INTEGER(unsigned(vcount) - 31);
+ if(bufferFilledonBuffer0 = (py/2)) then
+ rgb_out <= ram_x0(px/2);
+ elsif(bufferFilledonbuffer1 = (py/2)) then
+ rgb_out <= ram_x1(px/2);
+
+ else
+ rgb_out <= (others => '0');
+
+ end if;
+ end if;
+ -- pulse width
+ hsync <= '1';
+ if hcount < 97 then
+ hsync <= '0';
+ end if;
+
+ vsync <= '1';
+ if vcount < 3 then
+ vsync <= '0';
+ end if;
+
+ -- sync pulse time
+ hcount <= hcount + 1;
+
+ if hcount = 800 then
+ vcount <= vcount + 1;
+ hcount <= (others => '0');
+ end if;
+
+ if vcount = 521 then
+ vcount <= (others => '0');
+ end if;
+
+ end if;
+ -- output colors
+ RO <= rgb_out(11 downto 8);
+ GO <= rgb_out(7 downto 4);
+ BO <= rgb_out(3 downto 0);
+ end process;
+
+end Behavioral;