1 files changed, 105 insertions, 0 deletions
diff --git a/eindopdracht-progh2-vivado/eindopdracht-progh2-vivado.srcs/sources_1/pixeldata.vhd b/eindopdracht-progh2-vivado/eindopdracht-progh2-vivado.srcs/sources_1/pixeldata.vhd
new file mode 100644
index 0000000..28ef319
--- /dev/null
+++ b/eindopdracht-progh2-vivado/eindopdracht-progh2-vivado.srcs/sources_1/pixeldata.vhd
@@ -0,0 +1,105 @@
+library ieee;
+use ieee.std_logic_1164.all;
+use ieee.std_logic_unsigned.all;
+use ieee.numeric_std.all;
+
+entity pixeldata is
+	generic(
+		NOTE_HEAD_OFFSET : integer := 300; -- y coordinate of center of note head
+		NOTE_WIDTH : integer := 110; -- note image width
+		NOTE_HEIGHT : integer := 345; -- note image height
+		STAFF_SPACING : integer := 50; -- pitch between staff lines
+		STAFF_TOP_Y : integer := 220); -- y position of first staff line
+	port(
+		CLK: in std_logic; -- system clock
+		RESET: in std_logic; -- async reset
+		X, Y: in std_logic_vector(9 downto 0); -- pixel x/y
+		NOTE_IDX: in std_logic_vector(3 downto 0);
+		NOTE_WRONG: in std_logic;
+		RGB: out std_logic_vector(11 downto 0)); -- RGB output color
+end pixeldata;
+
+architecture Behavioral of pixeldata is
+	component half_note_rom is port (
+		clka : in std_logic;
+		addra : in std_logic_vector(15 downto 0);
+		douta : out std_logic_vector(0 downto 0));
+	end component;
+
+	signal iX, iY: unsigned (9 downto 0); -- pixel x/y
+	signal address : unsigned (15 downto 0);
+	signal data : std_logic_vector (0 downto 0);
+	signal NOTE_INDEX : integer;
+begin
+	iX <= unsigned(X);
+	iY <= unsigned(Y); 
+	NOTE_INDEX <= to_integer(unsigned(NOTE_IDX));
+
+	rom: component half_note_rom port map ( 
+		clka => CLK,
+		addra => std_logic_vector (address),
+		douta => data
+	);
+
+	process (CLK)
+		variable note_x : integer;
+		variable note_y : integer;
+		variable note_upright : std_logic;
+		variable pixel_index : integer;
+	begin
+		if RESET = '1' then
+			RGB <= (others => '0');
+			address <= (others => '0');
+			note_x := 0;
+			note_y := 0;
+			note_upright := '1';
+
+		elsif rising_edge(CLK) then
+			-- calculate which notes are displayed upright
+			case NOTE_IDX is
+				-- f,g,a upright note
+				when "0000" | "0001" | "0010" => note_upright := '1';
+				-- b,c,d,e,f hanging note
+				when others => note_upright := '0';
+			end case;
+
+			-- base note x position
+			note_x := 100;
+			-- base note y position (bottom staff y position, f)
+			note_y := STAFF_TOP_Y + 4 * STAFF_SPACING;
+			-- shift note y up by half a staff space for each increment of note_index
+			note_y := note_y - NOTE_INDEX * (STAFF_SPACING / 2);
+
+			-- shift up note depending on if displayed upside down or not
+			case note_upright is
+				when '0' => note_y := note_y - NOTE_HEIGHT + NOTE_HEAD_OFFSET;
+				when '1' => note_y := note_y - NOTE_HEAD_OFFSET;
+			end case;
+
+			pixel_index := to_integer(iX) - note_x + (to_integer(iY) - note_y) * NOTE_WIDTH;
+			if note_upright = '0' then
+				-- invert coordinates
+				pixel_index := NOTE_WIDTH * NOTE_HEIGHT - pixel_index;
+			end if;
+			address <= to_unsigned(pixel_index, address'length);
+
+			-- white background by default
+			RGB <= x"fff";
+
+			-- black staff lines
+			if Y = STAFF_TOP_Y + 0 * STAFF_SPACING then RGB <= x"000"; end if;
+			if Y = STAFF_TOP_Y + 1 * STAFF_SPACING then RGB <= x"000"; end if;
+			if Y = STAFF_TOP_Y + 2 * STAFF_SPACING then RGB <= x"000"; end if;
+			if Y = STAFF_TOP_Y + 3 * STAFF_SPACING then RGB <= x"000"; end if;
+			if Y = STAFF_TOP_Y + 4 * STAFF_SPACING then RGB <= x"000"; end if;
+
+			-- display note if in correct opsition
+			if (iX >= note_x) and (iX < (note_x + NOTE_WIDTH)) and
+			   (iY >= note_y) and (iY < (note_y + NOTE_HEIGHT)) then
+				if data(0) = '0' then
+					RGB <= x"f00" when NOTE_WRONG = '1' else x"000";
+				end if;
+			end if;
+		end if;
+	end process;
+end Behavioral;