Filtre passe-haut tueur

src/hdl/operativeUnit.vhd

@@ -25,7 +25,7 @@ entity operativeUnit is
 end entity operativeUnit;
 
 architecture arch_operativeUnit of operativeUnit is
-    type registerFile is array(0 to 15) of signed(15 downto 0);
+    type registerFile is array(0 to 31) of signed(15 downto 0);
     signal SR_coefRegister : registerFile;
 
     signal SR_shiftRegister : registerFile;           -- shift register file used to store and shift input samples
@@ -33,29 +33,72 @@ architecture arch_operativeUnit of operativeUnit is
     signal SC_multOperand2  : signed(15 downto 0);
     signal SC_MultResult    : signed(31 downto 0);    -- Result of the multiplication Xi*Hi
     signal SC_addResult     : signed(35 downto 0);    -- result of the accumulation addition
-    signal SR_sum           : signed(35 downto 0);    -- Accumulation register
+    signal SR_sum           : signed(35 downto 0);    -- Accumulation re gister
     signal SR_filteredSample: signed(15 downto 0);    -- filtered sample storage register
     signal SR_readAddress   : integer range 0 to 15;  -- register files read address
 
 begin
 
+
+    -- Low-pass filter provided with octave (or Matlab ;)) script :
+    -- pkg load signal
+    -- 
+    -- fs=44100
+    -- fn=fs/2
+    -- n=32
+    -- fc=1000
+    -- fHP=fir1(n-1,fc/fn,"high");
+    -- 
+    -- function quantized_signal = quantize(signal, q)
+    --     % Quantize the signal to q bits
+    --     max_val = 2^(q-1) - 1;
+    --     min_val = -2^(q-1);
+    --     quantized_signal = round(min(max(signal * 2^(q-1), min_val), max_val)) / 2^(q-1);
+    -- end
+    -- 
+    -- q=16
+    -- 
+    -- fHPq= quantize(fHP,q);
+    -- 
+    -- for i=1:n
+    --   printf("to_signed(%d,%d),\n", fHPq(i)*2^(q-1),q);
+    --  endfor
+
     -- Table to store the filter coefficients obtained with the previous script
-    SR_coefRegister <= (to_signed(317,16),
-                        to_signed(476,16),
-                        to_signed(925,16),
-                        to_signed(1589,16),
-                        to_signed(2354,16),
-                        to_signed(3087,16),
-                        to_signed(3661,16),
-                        to_signed(3975,16),
-                        to_signed(3975,16),
-                        to_signed(3661,16),
-                        to_signed(3087,16),
-                        to_signed(2354,16),
-                        to_signed(1589,16),
-                        to_signed(925,16),
-                        to_signed(476,16),
-                        to_signed(317,16)
+    
+  
+    SR_coefRegister <= (to_signed(-40,16),
+                        to_signed(-52,16),
+                        to_signed(-78,16),
+                        to_signed(-122,16),
+                        to_signed(-185,16),
+                        to_signed(-270,16),
+                        to_signed(-376,16),
+                        to_signed(-501,16),
+                        to_signed(-640,16),
+                        to_signed(-789,16),
+                        to_signed(-940,16),
+                        to_signed(-1086,16),
+                        to_signed(-1219,16),
+                        to_signed(-1331,16),
+                        to_signed(-1416,16),
+                        to_signed(-1470,16),
+                        to_signed(31316,16),
+                        to_signed(-1470,16),
+                        to_signed(-1416,16),
+                        to_signed(-1331,16),
+                        to_signed(-1219,16),
+                        to_signed(-1086,16),
+                        to_signed(-940,16),
+                        to_signed(-789,16),
+                        to_signed(-640,16),
+                        to_signed(-501,16),
+                        to_signed(-376,16),
+                        to_signed(-270,16),
+                        to_signed(-185,16),
+                        to_signed(-122,16),
+                        to_signed(-78,16),
+                        to_signed(-52,16)
                         );
     
     -- Process to describe the shift register storing the input samples
@@ -105,7 +148,7 @@ begin
     -- Register to store the accumulated value if the loadSum is active
     -- It also reduces the width of the sum to fit to the input and output
     -- signal widths (be careful with truncating/rounding)
-    sum_acc : process (I_clock, I_reset) is
+    sum_acc : process (I_clock, I_reset) is 
     begin
         if I_reset = '1' then               -- asynchronous reset (active high)
             SR_sum <= (others => '0');