├── .gitignore ├── img ├── objbuf.png └── pattern.png ├── makefile ├── README.md ├── tools └── display.html ├── rtl ├── pattern_generator.vhd ├── timing_generator.vhd ├── vga_timing_pkg.vhd └── objectbuffer.vhd ├── tb └── tb_display.vhd └── LICENSE /.gitignore: -------------------------------------------------------------------------------- 1 | debug/ 2 | rgb.txt -------------------------------------------------------------------------------- /img/objbuf.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/fcayci/vhdl-display-simulator/HEAD/img/objbuf.png -------------------------------------------------------------------------------- /img/pattern.png: -------------------------------------------------------------------------------- https://raw.githubusercontent.com/fcayci/vhdl-display-simulator/HEAD/img/pattern.png -------------------------------------------------------------------------------- /makefile: -------------------------------------------------------------------------------- 1 | # author: Furkan Cayci, 2018 2 | # description: 3 | # add ghdl to your PATH for simulation 4 | 5 | CC = ghdl 6 | ARCHNAME = tb_display 7 | STOPTIME = 100ms 8 | 9 | VHDL_SOURCES = rtl/vga_timing_pkg.vhd 10 | VHDL_SOURCES += rtl/timing_generator.vhd 11 | VHDL_SOURCES += rtl/objectbuffer.vhd 12 | VHDL_SOURCES += rtl/pattern_generator.vhd 13 | 14 | TB = tb/$(ARCHNAME).vhd 15 | WORKDIR = debug 16 | 17 | CFLAGS = --ieee=synopsys 18 | CFLAGS += --std=08 # enable ieee 2008 standard 19 | CFLAGS += --warn-binding 20 | CFLAGS += --warn-no-library # turn off warning on design replace with same name 21 | 22 | .PHONY: all 23 | all: check analyze 24 | @echo ">>> completed..." 25 | 26 | .PHONY: check 27 | check: 28 | @echo ">>> check syntax on all designs..." 29 | @$(CC) -s $(CFLAGS) $(VHDL_SOURCES) $(TB) 30 | 31 | .PHONY: analyze 32 | analyze: 33 | @echo ">>> analyzing designs..." 34 | @mkdir -p $(WORKDIR) 35 | @$(CC) -a --workdir=$(WORKDIR) $(CFLAGS) $(VHDL_SOURCES) $(TB) 36 | 37 | .PHONY: simulate 38 | simulate: clean analyze 39 | @echo ">>> creating rgb file for:" $(TB) 40 | @$(CC) --elab-run --workdir=$(WORKDIR) $(CFLAGS) \ 41 | -o $(WORKDIR)/$(ARCHNAME).bin $(ARCHNAME) \ 42 | --stop-time=$(STOPTIME) 43 | 44 | .PHONY: clean 45 | clean: 46 | @echo ">>> cleaning design..." 47 | @ghdl --remove --workdir=$(WORKDIR) 48 | @rm -f $(WORKDIR)/* 49 | @rm -rf $(WORKDIR) 50 | @echo ">>> done..." -------------------------------------------------------------------------------- /README.md: -------------------------------------------------------------------------------- 1 | # vhdl-display-simulator 2 | 3 | Screen Display Simulator written in VHDL and JS. Generates RGB pixel data file from VHDL simulation and displays the pixels on the browser. Expects 24-bit RGB data. 4 | 5 | Example output for `pattern_generator.vhd` and `objectbuffer.vhd` are shown below. 6 | 7 | ![pattern gen](img/pattern.png) ![object buffer](img/objbuf.png) 8 | 9 | ## Procedure 10 | 11 | ### Using ISIM 12 | 13 | 1. create a project and import files in the `rtl` directory. 14 | 2. add the testbench from `tb` directory and run the testbench until `vsync` is asserted. 15 | 3. `rgb.txt` data should be generated under project folder. 16 | 4. open `display.html` from `tools` directory in your browser, load the generated `rgb.txt` data, choose the resolution and hit `Render screen` button. 17 | 18 | ### Using GHDL 19 | 20 | NOTE: Windows support is not added yet. 21 | 22 | 0. Install GHDL and add it to your path. 23 | 1. run `make` to check VHDL syntax in your code 24 | 2. run `make simulate` to create the RGB data. This runs the `tb_display.vhd` testbench for one full frame. It stores pixel color data per clock when in the active video area. Saves in a file called `rgb.txt`. This will take a couple seconds and will take around ~10MB space. 25 | 3. open `display.html` from `tools` directory in your browser, choose the resolution and hit `Render screen` button. 26 | 27 | ## Files 28 | 29 | ``` 30 | +- makefile : GHDL simulation / RGB data generation 31 | +- rtl/ 32 | | -- timing_generator.vhd : timing generator 33 | | -- pattern_generator.vhd : color spectrum pattern 34 | | -- objectbuffer.vhd : generates objects 35 | +- tb/ 36 | | -- tb_display.vhd : generates rgb values for one frame 37 | +- tools/ 38 | |-- display.html : HTML / JS code to display the generated rgb data 39 | ``` 40 | -------------------------------------------------------------------------------- /tools/display.html: -------------------------------------------------------------------------------- 1 | 2 | 3 | 4 | Display Simulator 5 | 6 | 7 |

Display Simulator

8 |

Choose the rgb.txt file that is generated from simulation

9 | 10 | Choose resolution: 11 | 16 | 17 |
18 |
19 | 20 | 21 | 76 | 79 | 80 | -------------------------------------------------------------------------------- /rtl/pattern_generator.vhd: -------------------------------------------------------------------------------- 1 | -- author: Furkan Cayci, 2018 2 | -- description: video pattern generator based on the active areas 3 | -- displays color spectrum 4 | 5 | library ieee; 6 | use ieee.std_logic_1164.all; 7 | use ieee.numeric_std.all; 8 | 9 | entity pattern_generator is 10 | port( 11 | clk : in std_logic; 12 | video_active : in std_logic; 13 | rgb : out std_logic_vector(23 downto 0) 14 | ); 15 | end pattern_generator; 16 | 17 | architecture rtl of pattern_generator is 18 | type state_type is (s0, s1, s2, s3, s4, s5); 19 | signal state : state_type := s0; 20 | 21 | signal r : unsigned(7 downto 0) := (others => '1'); 22 | signal b : unsigned(7 downto 0) := (others => '0'); 23 | signal g : unsigned(7 downto 0) := (others => '0'); 24 | begin 25 | 26 | rgb <= std_logic_vector(r & g & b); 27 | 28 | -- color spectrum process 29 | process(clk) is 30 | begin 31 | if rising_edge(clk) then 32 | if video_active = '1' then 33 | case state is 34 | when s0 => 35 | if g = 255 then 36 | state <= s1; 37 | else 38 | g <= g + 1; 39 | end if; 40 | when s1 => 41 | if r = 0 then 42 | state <= s2; 43 | else 44 | r <= r - 1; 45 | end if; 46 | when s2 => 47 | if b = 255 then 48 | state <= s3; 49 | else 50 | b <= b + 1; 51 | end if; 52 | when s3 => 53 | if g = 0 then 54 | state <= s4; 55 | else 56 | g <= g - 1; 57 | end if; 58 | when s4 => 59 | if r = 255 then 60 | state <= s5; 61 | else 62 | r <= r + 1; 63 | end if; 64 | when s5 => 65 | if b = 0 then 66 | state <= s0; 67 | else 68 | b <= b - 1; 69 | end if; 70 | end case; 71 | else 72 | r <= (others => '1'); 73 | g <= (others => '0'); 74 | b <= (others => '0'); 75 | state <= s0; 76 | end if; 77 | end if; 78 | end process; 79 | 80 | end rtl; 81 | -------------------------------------------------------------------------------- /rtl/timing_generator.vhd: -------------------------------------------------------------------------------- 1 | -- author: Furkan Cayci, 2018 2 | -- description: video timing generator 3 | -- choose between hd1080p, hd720p, svga, and vga 4 | 5 | library ieee; 6 | use ieee.std_logic_1164.all; 7 | use ieee.numeric_std.all; 8 | 9 | library work; 10 | use work.vga_timing_pkg.all; 11 | 12 | entity timing_generator is 13 | generic ( 14 | RESOLUTION : string := "HD720P"; -- hd1080p, hd720p, svga, vga 15 | GEN_PIX_LOC : boolean := true; 16 | OBJECT_SIZE : natural := 16 17 | ); 18 | port( 19 | clk : in std_logic; 20 | hsync, vsync : out std_logic; 21 | video_active : out std_logic; 22 | pixel_x : out std_logic_vector(OBJECT_SIZE-1 downto 0); 23 | pixel_y : out std_logic_vector(OBJECT_SIZE-1 downto 0) 24 | ); 25 | end timing_generator; 26 | 27 | architecture rtl of timing_generator is 28 | 29 | -- horizontal and vertical counters 30 | signal hcount : unsigned(OBJECT_SIZE-1 downto 0) := (others => '0'); 31 | signal vcount : unsigned(OBJECT_SIZE-1 downto 0) := (others => '0'); 32 | signal timings : video_timing_type := HD720P_TIMING; 33 | 34 | begin 35 | 36 | timings <= HD1080P_TIMING when RESOLUTION = "HD1080P" else 37 | HD720P_TIMING when RESOLUTION = "HD720P" else 38 | SVGA_TIMING when RESOLUTION = "SVGA" else 39 | VGA_TIMING when RESOLUTION = "VGA"; 40 | 41 | -- pixel counters 42 | process (clk) is 43 | begin 44 | if rising_edge(clk) then 45 | if (hcount = timings.H_TOTAL) then 46 | hcount <= (others => '0'); 47 | if (vcount = timings.V_TOTAL) then 48 | vcount <= (others => '0'); 49 | else 50 | vcount <= vcount + 1; 51 | end if; 52 | else 53 | hcount <= hcount + 1; 54 | end if; 55 | end if; 56 | end process; 57 | 58 | -- generate video_active, hsync, and vsync signals based on the counters 59 | video_active <= timings.ACTIVE when (hcount < timings.H_VIDEO) and (vcount < timings.V_VIDEO ) else not timings.ACTIVE; 60 | hsync <= timings.H_POL when (hcount >= timings.H_VIDEO + timings.H_FP) and (hcount < timings.H_TOTAL - timings.H_BP) else not timings.H_POL; 61 | vsync <= timings.V_POL when (vcount >= timings.V_VIDEO + timings.V_FP) and (vcount < timings.V_TOTAL - timings.V_BP) else not timings.V_POL; 62 | 63 | g0: if GEN_PIX_LOC = true generate 64 | begin 65 | -- send pixel locations 66 | pixel_x <= std_logic_vector(hcount) when hcount < timings.H_VIDEO else (others => '0'); 67 | pixel_y <= std_logic_vector(vcount) when vcount < timings.V_VIDEO else (others => '0'); 68 | end generate; 69 | 70 | g1: if GEN_PIX_LOC = false generate 71 | begin 72 | -- send pixel locations 73 | pixel_x <= (others => '0'); 74 | pixel_y <= (others => '0'); 75 | end generate; 76 | end rtl; 77 | -------------------------------------------------------------------------------- /tb/tb_display.vhd: -------------------------------------------------------------------------------- 1 | -- author: Furkan Cayci, 2018 2 | -- description: display testbench 3 | -- generates a txt file to display on html canvas 4 | -- only supports 24-bit RGB values 5 | 6 | library ieee; 7 | use ieee.std_logic_1164.all; 8 | use ieee.numeric_std.all; 9 | use std.textio.all; 10 | use ieee.std_logic_textio.all; 11 | 12 | entity tb_display is 13 | end tb_display; 14 | 15 | architecture rtl of tb_display is 16 | 17 | constant RESOLUTION : string := "HD720P"; -- HD720P, SVGA, VGA 18 | constant GEN_PIX_LOC : boolean := true; 19 | constant OBJECT_SIZE : natural := 16; 20 | constant PIXEL_SIZE : natural := 24; 21 | constant clk_period : time := 8 ns; 22 | constant reset_time : time := 204 ns; 23 | constant frame_time : time := 9.6 ms; 24 | 25 | signal clk : std_logic; 26 | signal hsync, vsync : std_logic; 27 | signal video_active : std_logic; 28 | signal rgb : std_logic_vector(PIXEL_SIZE-1 downto 0); 29 | signal pixel_x : std_logic_vector(OBJECT_SIZE-1 downto 0); 30 | signal pixel_y : std_logic_vector(OBJECT_SIZE-1 downto 0); 31 | 32 | -- change the object locations 33 | signal object1x : std_logic_vector(OBJECT_SIZE-1 downto 0) := std_logic_vector(to_unsigned(500, OBJECT_SIZE)); 34 | signal object1y : std_logic_vector(OBJECT_SIZE-1 downto 0) := std_logic_vector(to_unsigned(140, OBJECT_SIZE)); 35 | signal object2x : std_logic_vector(OBJECT_SIZE-1 downto 0) := std_logic_vector(to_unsigned(240, OBJECT_SIZE)); 36 | signal object2y : std_logic_vector(OBJECT_SIZE-1 downto 0) := std_logic_vector(to_unsigned(340, OBJECT_SIZE)); 37 | signal backgrnd_rgb : std_logic_vector(PIXEL_SIZE-1 downto 0) := x"FFFF00"; -- yellow 38 | 39 | begin 40 | 41 | -- timing generator 42 | u_t : entity work.timing_generator(rtl) 43 | generic map (RESOLUTION=>RESOLUTION, GEN_PIX_LOC=>GEN_PIX_LOC, 44 | OBJECT_SIZE=>OBJECT_SIZE) 45 | port map (clk=>clk, hsync=>hsync, vsync=>vsync, video_active=>video_active, 46 | pixel_x=>pixel_x, pixel_y=>pixel_y); 47 | 48 | -- connect pattern generator 49 | -- uut0 : entity work.pattern_generator(rtl) 50 | -- port map(clk=>clk, video_active=>video_active, rgb=>rgb); 51 | 52 | -- connect object buffer 53 | uut0 : entity work.objectbuffer(rtl) 54 | generic map (OBJECT_SIZE=>OBJECT_SIZE, PIXEL_SIZE=>PIXEL_SIZE) 55 | port map (video_active=>video_active, pixel_x=>pixel_x, pixel_y=>pixel_y, 56 | object1x=>object1x, object1y=>object1y, 57 | object2x=>object2x, object2y=>object2y, 58 | backgrnd_rgb=>backgrnd_rgb, rgb=>rgb); 59 | 60 | -- generate clock 61 | clk_generate: 62 | process 63 | begin 64 | for i in 0 to frame_time / clk_period loop 65 | wait for clk_period/2; 66 | clk <= '1'; 67 | wait for clk_period/2; 68 | clk <= '0'; 69 | end loop; 70 | wait; 71 | end process; 72 | 73 | -- record values 74 | process(clk) is 75 | file DISP_FILE : text open write_mode is "rgb.txt"; 76 | variable DISP_LINE : line; 77 | variable h : std_logic := '0'; 78 | begin 79 | if rising_edge(clk) then 80 | if video_active = '1' then 81 | write(DISP_LINE, to_integer(unsigned(rgb))); 82 | write(DISP_LINE, ','); 83 | h := '1'; 84 | end if; 85 | 86 | -- Note that in VGA hsync polarity should be reversed 87 | if hsync = '1' and h = '1' then 88 | h := '0'; 89 | writeline(DISP_FILE, DISP_LINE); 90 | end if; 91 | 92 | -- Note that in VGA vsync polarity should be reversed 93 | if vsync = '1' then 94 | assert false report "completed...ignore following error messages" severity FAILURE; 95 | end if; 96 | end if; 97 | end process; 98 | 99 | end rtl; -------------------------------------------------------------------------------- /rtl/vga_timing_pkg.vhd: -------------------------------------------------------------------------------- 1 | -- author: Furkan Cayci, 2019 2 | -- description: holds timing information 3 | 4 | library ieee; 5 | use ieee.std_logic_1164.all; 6 | 7 | package vga_timing_pkg is 8 | 9 | type video_timing_type is record 10 | H_VIDEO : integer; 11 | H_FP : integer; 12 | H_SYNC : integer; 13 | H_BP : integer; 14 | H_TOTAL : integer; 15 | V_VIDEO : integer; 16 | V_FP : integer; 17 | V_SYNC : integer; 18 | V_BP : integer; 19 | V_TOTAL : integer; 20 | H_POL : std_logic; 21 | V_POL : std_logic; 22 | ACTIVE : std_logic; 23 | end record; 24 | 25 | -- HD1080p timing 26 | -- screen area 1920x1080 @60 Hz 27 | -- horizontal : 1920 visible + 88 front porch (fp) + 44 hsync + 148 back porch = 2200 pixels 28 | -- vertical : 1080 visible + 4 front porch (fp) + 5 vsync + 36 back porch = 1125 pixels 29 | -- Total area 2200x1125 30 | -- clk input should be 148.5 MHz signal (2200 * 1125 * 60) 31 | -- hsync and vsync are positive polarity 32 | 33 | constant HD1080P_TIMING : video_timing_type := ( 34 | H_VIDEO => 1920, 35 | H_FP => 88, 36 | H_SYNC => 44, 37 | H_BP => 148, 38 | H_TOTAL => 2200, 39 | V_VIDEO => 1080, 40 | V_FP => 4, 41 | V_SYNC => 5, 42 | V_BP => 36, 43 | V_TOTAL => 1125, 44 | H_POL => '1', 45 | V_POL => '1', 46 | ACTIVE => '1' 47 | ); 48 | 49 | -- HD720p timing 50 | -- screen area 1280x720 @60 Hz 51 | -- horizontal : 1280 visible + 72 front porch (fp) + 80 hsync + 216 back porch = 1648 pixels 52 | -- vertical : 720 visible + 3 front porch (fp) + 5 vsync + 22 back porch = 750 pixels 53 | -- Total area 1648x750 54 | -- clk input should be 74.25 MHz signal (1650 * 750 * 60) 55 | -- hsync and vsync are positive polarity 56 | 57 | constant HD720P_TIMING : video_timing_type := ( 58 | H_VIDEO => 1280, 59 | H_FP => 72, 60 | H_SYNC => 80, 61 | H_BP => 216, 62 | H_TOTAL => 1648, 63 | V_VIDEO => 720, 64 | V_FP => 3, 65 | V_SYNC => 5, 66 | V_BP => 22, 67 | V_TOTAL => 750, 68 | H_POL => '1', 69 | V_POL => '1', 70 | ACTIVE => '1' 71 | ); 72 | 73 | -- SVGA timing 74 | -- screen area 800x600 @60 Hz 75 | -- horizontal : 800 visible + 40 front porch (fp) + 128 hsync + 88 back porch = 1056 pixels 76 | -- vertical : 600 visible + 1 front porch (fp) + 4 vsync + 23 back porch = 628 pixels 77 | -- Total area 1056x628 78 | -- clk input should be 40 MHz signal (1056 * 628 * 60) 79 | -- hsync and vsync are positive polarity 80 | 81 | constant SVGA_TIMING : video_timing_type := ( 82 | H_VIDEO => 800, 83 | H_FP => 40, 84 | H_SYNC => 128, 85 | H_BP => 88, 86 | H_TOTAL => 1056, 87 | V_VIDEO => 600, 88 | V_FP => 1, 89 | V_SYNC => 4, 90 | V_BP => 23, 91 | V_TOTAL => 628, 92 | H_POL => '1', 93 | V_POL => '1', 94 | ACTIVE => '1' 95 | ); 96 | 97 | -- VGA timing 98 | -- screen area 640x480 @60 Hz 99 | -- horizontal : 640 visible + 16 front porch (fp) + 96 hsync + 48 back porch = 800 pixels 100 | -- vertical : 480 visible + 10 front porch (fp) + 2 vsync + 33 back porch = 525 pixels 101 | -- Total area 800x525 102 | -- clk input should be 25 MHz signal (800 * 525 * 60) 103 | -- hsync and vsync are negative polarity 104 | 105 | constant VGA_TIMING : video_timing_type := ( 106 | H_VIDEO => 640, 107 | H_FP => 16, 108 | H_SYNC => 96, 109 | H_BP => 48, 110 | H_TOTAL => 800, 111 | V_VIDEO => 480, 112 | V_FP => 10, 113 | V_SYNC => 2, 114 | V_BP => 33, 115 | V_TOTAL => 525, 116 | H_POL => '0', 117 | V_POL => '0', 118 | ACTIVE => '1' 119 | ); 120 | 121 | end package vga_timing_pkg; 122 | 123 | package body vga_timing_pkg is 124 | end package body vga_timing_pkg; 125 | -------------------------------------------------------------------------------- /rtl/objectbuffer.vhd: -------------------------------------------------------------------------------- 1 | -- author: Furkan Cayci, 2018 2 | -- description: object buffer that holds the objects to display 3 | -- object locations can be controlled from upper level 4 | -- example contains a wall, a rectanble box and a round ball 5 | 6 | library ieee; 7 | use ieee.std_logic_1164.all; 8 | use ieee.numeric_std.all; 9 | 10 | entity objectbuffer is 11 | generic ( 12 | OBJECT_SIZE : natural := 16; 13 | PIXEL_SIZE : natural := 24 14 | ); 15 | port ( 16 | video_active : in std_logic; 17 | pixel_x, pixel_y : in std_logic_vector(OBJECT_SIZE-1 downto 0); 18 | object1x, object1y : in std_logic_vector(OBJECT_SIZE-1 downto 0); 19 | object2x, object2y : in std_logic_vector(OBJECT_SIZE-1 downto 0); 20 | backgrnd_rgb : in std_logic_vector(PIXEL_SIZE-1 downto 0); 21 | rgb : out std_logic_vector(PIXEL_SIZE-1 downto 0) 22 | ); 23 | end objectbuffer; 24 | 25 | architecture rtl of objectbuffer is 26 | -- create a 5 pixel vertical wall 27 | constant WALL_X_L: integer := 60; 28 | constant WALL_X_R: integer := 65; 29 | 30 | -- 1st object is a vertical box 48x8 pixel 31 | constant BOX_SIZE_X: integer := 8; 32 | constant BOX_SIZE_Y: integer := 48; 33 | -- x, y coordinates of the box 34 | signal box_x_l : unsigned (OBJECT_SIZE-1 downto 0); 35 | signal box_y_t : unsigned (OBJECT_SIZE-1 downto 0); 36 | signal box_x_r : unsigned (OBJECT_SIZE-1 downto 0); 37 | signal box_y_b : unsigned (OBJECT_SIZE-1 downto 0); 38 | 39 | -- 2nd object is a ball 40 | constant BALL_SIZE: integer:=8; 41 | type rom_type is array (0 to 7) of std_logic_vector(0 to 7); 42 | 43 | constant BALL_ROM: rom_type := ( 44 | "00111100", -- **** 45 | "01111110", -- ****** 46 | "11111111", -- ******** 47 | "11111111", -- ******** 48 | "11111111", -- ******** 49 | "11111111", -- ******** 50 | "01111110", -- ****** 51 | "00111100" -- **** 52 | ); 53 | 54 | signal rom_addr, rom_col: unsigned(0 to 2); 55 | signal rom_bit: std_logic; 56 | -- x, y coordinates of the ball 57 | signal ball_x_l : unsigned(OBJECT_SIZE-1 downto 0); 58 | signal ball_y_t : unsigned(OBJECT_SIZE-1 downto 0); 59 | signal ball_x_r : unsigned(OBJECT_SIZE-1 downto 0); 60 | signal ball_y_b : unsigned(OBJECT_SIZE-1 downto 0); 61 | 62 | -- signals that holds the x, y coordinates 63 | signal pix_x, pix_y: unsigned (OBJECT_SIZE-1 downto 0); 64 | 65 | signal wall_on, box_on, square_ball_on, ball_on: std_logic; 66 | signal wall_rgb, box_rgb, ball_rgb: std_logic_vector(23 downto 0); 67 | 68 | begin 69 | 70 | pix_x <= unsigned(pixel_x); 71 | pix_y <= unsigned(pixel_y); 72 | 73 | -- draw wall and color 74 | wall_on <= '1' when WALL_X_L<=pix_x and pix_x<=WALL_X_R else '0'; 75 | wall_rgb <= x"0000FF"; -- blue 76 | 77 | -- draw box and color 78 | -- calculate the coordinates 79 | box_x_l <= unsigned(object1x); 80 | box_y_t <= unsigned(object1y); 81 | box_x_r <= box_x_l + BOX_SIZE_X - 1; 82 | box_y_b <= box_y_t + BOX_SIZE_Y - 1; 83 | box_on <= '1' when box_x_l<=pix_x and pix_x<=box_x_r and 84 | box_y_t<=pix_y and pix_y<=box_y_b else 85 | '0'; 86 | -- box rgb output 87 | box_rgb <= x"00FF00"; --green 88 | 89 | -- draw ball and color 90 | -- calculate the coordinates 91 | ball_x_l <= unsigned(object2x); 92 | ball_y_t <= unsigned(object2y); 93 | ball_x_r <= ball_x_l + BALL_SIZE - 1; 94 | ball_y_b <= ball_y_t + BALL_SIZE - 1; 95 | 96 | square_ball_on <= '1' when ball_x_l<=pix_x and pix_x<=ball_x_r and 97 | ball_y_t<=pix_y and pix_y<=ball_y_b else 98 | '0'; 99 | -- map current pixel location to ROM addr/col 100 | rom_addr <= pix_y(2 downto 0) - ball_y_t(2 downto 0); 101 | rom_col <= pix_x(2 downto 0) - ball_x_l(2 downto 0); 102 | rom_bit <= BALL_ROM(to_integer(rom_addr))(to_integer(rom_col)); 103 | -- pixel within ball 104 | ball_on <= '1' when square_ball_on='1' and rom_bit='1' else '0'; 105 | -- ball rgb output 106 | ball_rgb <= x"FF0000"; -- red 107 | 108 | -- display the image based on who is active 109 | -- note that the order is important 110 | process(video_active, wall_on, box_on, wall_rgb, box_rgb, ball_rgb, backgrnd_rgb, ball_on) is 111 | begin 112 | if video_active='0' then 113 | rgb <= x"000000"; --blank 114 | else 115 | if wall_on='1' then 116 | rgb <= wall_rgb; 117 | elsif ball_on='1' then 118 | rgb <= ball_rgb; 119 | elsif box_on='1' then 120 | rgb <= box_rgb; 121 | else 122 | rgb <= backgrnd_rgb; -- x"FFFF00"; -- yellow background 123 | end if; 124 | end if; 125 | end process; 126 | 127 | end rtl; -------------------------------------------------------------------------------- /LICENSE: -------------------------------------------------------------------------------- 1 | GNU GENERAL PUBLIC LICENSE 2 | Version 3, 29 June 2007 3 | 4 | Copyright (C) 2007 Free Software Foundation, Inc. 5 | Everyone is permitted to copy and distribute verbatim copies 6 | of this license document, but changing it is not allowed. 7 | 8 | Preamble 9 | 10 | The GNU General Public License is a free, copyleft license for 11 | software and other kinds of works. 12 | 13 | The licenses for most software and other practical works are designed 14 | to take away your freedom to share and change the works. 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Such new versions will 567 | be similar in spirit to the present version, but may differ in detail to 568 | address new problems or concerns. 569 | 570 | Each version is given a distinguishing version number. If the 571 | Program specifies that a certain numbered version of the GNU General 572 | Public License "or any later version" applies to it, you have the 573 | option of following the terms and conditions either of that numbered 574 | version or of any later version published by the Free Software 575 | Foundation. If the Program does not specify a version number of the 576 | GNU General Public License, you may choose any version ever published 577 | by the Free Software Foundation. 578 | 579 | If the Program specifies that a proxy can decide which future 580 | versions of the GNU General Public License can be used, that proxy's 581 | public statement of acceptance of a version permanently authorizes you 582 | to choose that version for the Program. 583 | 584 | Later license versions may give you additional or different 585 | permissions. However, no additional obligations are imposed on any 586 | author or copyright holder as a result of your choosing to follow a 587 | later version. 588 | 589 | 15. Disclaimer of Warranty. 590 | 591 | THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT PERMITTED BY 592 | APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE COPYRIGHT 593 | HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM "AS IS" WITHOUT WARRANTY 594 | OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED TO, 595 | THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 596 | PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM 597 | IS WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF 598 | ALL NECESSARY SERVICING, REPAIR OR CORRECTION. 599 | 600 | 16. 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Interpretation of Sections 15 and 16. 613 | 614 | If the disclaimer of warranty and limitation of liability provided 615 | above cannot be given local legal effect according to their terms, 616 | reviewing courts shall apply local law that most closely approximates 617 | an absolute waiver of all civil liability in connection with the 618 | Program, unless a warranty or assumption of liability accompanies a 619 | copy of the Program in return for a fee. 620 | 621 | END OF TERMS AND CONDITIONS 622 | 623 | How to Apply These Terms to Your New Programs 624 | 625 | If you develop a new program, and you want it to be of the greatest 626 | possible use to the public, the best way to achieve this is to make it 627 | free software which everyone can redistribute and change under these terms. 628 | 629 | To do so, attach the following notices to the program. It is safest 630 | to attach them to the start of each source file to most effectively 631 | state the exclusion of warranty; and each file should have at least 632 | the "copyright" line and a pointer to where the full notice is found. 633 | 634 | 635 | Copyright (C) 636 | 637 | This program is free software: you can redistribute it and/or modify 638 | it under the terms of the GNU General Public License as published by 639 | the Free Software Foundation, either version 3 of the License, or 640 | (at your option) any later version. 641 | 642 | This program is distributed in the hope that it will be useful, 643 | but WITHOUT ANY WARRANTY; without even the implied warranty of 644 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 645 | GNU General Public License for more details. 646 | 647 | You should have received a copy of the GNU General Public License 648 | along with this program. If not, see . 649 | 650 | Also add information on how to contact you by electronic and paper mail. 651 | 652 | If the program does terminal interaction, make it output a short 653 | notice like this when it starts in an interactive mode: 654 | 655 | Copyright (C) 656 | This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'. 657 | This is free software, and you are welcome to redistribute it 658 | under certain conditions; type `show c' for details. 659 | 660 | The hypothetical commands `show w' and `show c' should show the appropriate 661 | parts of the General Public License. Of course, your program's commands 662 | might be different; for a GUI interface, you would use an "about box". 663 | 664 | You should also get your employer (if you work as a programmer) or school, 665 | if any, to sign a "copyright disclaimer" for the program, if necessary. 666 | For more information on this, and how to apply and follow the GNU GPL, see 667 | . 668 | 669 | The GNU General Public License does not permit incorporating your program 670 | into proprietary programs. If your program is a subroutine library, you 671 | may consider it more useful to permit linking proprietary applications with 672 | the library. If this is what you want to do, use the GNU Lesser General 673 | Public License instead of this License. But first, please read 674 | . 675 | --------------------------------------------------------------------------------