Merge pull request #15 from UnavailableDev/dev

APU LUT / Calulations

1 files changed, 24 insertions, 20 deletions

diff --git a/basys3/basys3.srcs/apu_note_to_frequency.vhd b/basys3/basys3.srcs/apu_note_to_frequency.vhd
index 7e02c75..8a7b3d6 100644
--- a/basys3/basys3.srcs/apu_note_to_frequency.vhd
+++ b/basys3/basys3.srcs/apu_note_to_frequency.vhd
@@ -5,31 +5,35 @@ use ieee.numeric_std.all;
 entity apu_note_to_frequency is port (
 	-- clk : in std_logic;
 	-- rst : in std_logic;
-	data : in std_logic_vector(7 downto 0);
-	freq : out std_logic_vector(11 downto 0)); --frequency
+	data : in std_logic_vector(6 downto 0);
+	freq : out std_logic_vector(11 downto 0)); -- frequency
 end entity;
 
 architecture Behavioral of apu_note_to_frequency is
 	signal buff_small: std_logic_vector(7 downto 0) := (others => '0');
-	signal buff: std_logic_vector(15 downto 0) := (others => '0');
+	signal buff: std_logic_vector(11 downto 0) := (others => '0');
 	signal shift: integer;
 begin
-	shift <= to_integer(unsigned(data(2 downto 0)));
-	buff_small <= 
-		x"f0" when data(7 downto 3) = (x"c" & '0') else -- C	496
-		x"d0" when data(7 downto 3) = (x"c" & '1') else -- C# 464
-		x"b0" when data(7 downto 3) = (x"d" & '0') else -- D	432
-		x"a0" when data(7 downto 3) = (x"d" & '1') else -- D# 416
-		x"80" when data(7 downto 3) = (x"e" & '0') else -- E	384
-		x"70" when data(7 downto 3) = (x"f" & '0') else -- F	368
-		x"58" when data(7 downto 3) = (x"f" & '1') else -- F# 344
-		x"40" when data(7 downto 3) = (x"8" & '0') else -- G	320
-		x"30" when data(7 downto 3) = (x"8" & '1') else -- G# 304
-		x"20" when data(7 downto 3) = (x"a" & '0') else -- A	288
-		x"10" when data(7 downto 3) = (x"a" & '1') else -- A# 272
-		x"00" when data(7 downto 3) = (x"b" & '0') else -- B	256
-		x"01";
 
-	buff <= x"1" & buff_small;
-	freq <= (others => '0') & buff(15 downto shift); -- bitshift values out (or div by powers of 2)
+    shift <= to_integer(unsigned( data(2 downto 0) ));
+
+    buff <= 
+        x"1F0" when data(6 downto 3) = (x"1") else -- C     496
+        x"1D0" when data(6 downto 3) = (x"2") else -- C#/Db 464
+        x"1B0" when data(6 downto 3) = (x"3") else -- D     432
+        x"1A0" when data(6 downto 3) = (x"4") else -- D#/Eb 416
+        x"180" when data(6 downto 3) = (x"5") else -- E     384
+        x"170" when data(6 downto 3) = (x"6") else -- F     368
+        x"158" when data(6 downto 3) = (x"7") else -- F#/Gb 344
+        x"140" when data(6 downto 3) = (x"8") else -- G     320
+        x"130" when data(6 downto 3) = (x"9") else -- G#/Ab 304
+        x"120" when data(6 downto 3) = (x"A") else -- A     288
+        x"110" when data(6 downto 3) = (x"B") else -- A#/Bb 272
+        x"100" when data(6 downto 3) = (x"C") else -- B     256
+        x"000";
+
+    -- buff <= x"1" & buff_small;
+    freq <= std_logic_vector( shift_right(unsigned(buff), shift) );
+    -- freq <= (others => '0') & buff(11 downto shift); -- bitshift values out (or div by powers of 2) -- TODO: NO WORKY!!! (concat (others => '0');)
+
 end architecture;