Added a converter for the bit depth and volume of audio samples

labs/3_music/3_10_spectrum_analyzer/converter.sv

@@ -7,7 +7,7 @@ module converter
 (
     input  logic               clk,
     input  logic               rst,
-    input  logic signed [ 9:0] [10:0] in,
+    input  logic signed [ 9:0][10:0] in,
     input  logic        [16:0] band_count,
     output logic        [10:0] rms_out
 );
@@ -17,11 +17,11 @@ module converter
     logic                      pulse_out;
     logic               [ 4:0] switch     = '0;
     logic        signed [10:0] q00, q90;
-    logic        signed [15:0] i_filtered = '0;
-    logic        signed [15:0] q_filtered = '0;
-    logic               [15:0] abs_i, abs_q;
+    logic        signed [16:0] i_filtered = '0;
+    logic        signed [16:0] q_filtered = '0;
+    logic               [16:0] abs_i, abs_q;
     logic               [16:0] sum_abs;
-    logic               [17:0] ema        = '0;
+    logic               [16:0] ema        = '0;
 
     // Reference frequency * 32 of control pulses generator
     always_ff @(posedge clk or posedge rst) begin
@@ -209,8 +209,8 @@ module converter
     end
 
     // Rectifier
-    assign abs_i = i_filtered [15] ? -i_filtered : i_filtered;
-    assign abs_q = q_filtered [15] ? -q_filtered : q_filtered;
+    assign abs_i = i_filtered[16] ? -i_filtered : i_filtered;
+    assign abs_q = q_filtered[16] ? -q_filtered : q_filtered;
     assign sum_abs = abs_i + abs_q;
 
     // Averaging

labs/3_music/3_10_spectrum_analyzer/gtkwave.tcl

@@ -5,14 +5,16 @@ set all_signals [list]
 lappend all_signals tb.sound
 lappend all_signals tb.i_converter.q00
 lappend all_signals tb.i_converter.q90
+lappend all_signals tb.i_converter.switch
 lappend all_signals tb.i_converter.i_filtered
 lappend all_signals tb.i_converter.q_filtered
 lappend all_signals tb.i_converter.abs_i
 lappend all_signals tb.i_converter.abs_q
 lappend all_signals tb.i_converter.sum_abs
 lappend all_signals tb.i_converter.ema
 lappend all_signals tb.i_converter.rms_out
-lappend all_signals tb.i_converter.switch
+lappend all_signals tb.i_convert.ina
+lappend all_signals tb.i_convert.ing
 
 set num_added [ gtkwave::addSignalsFromList $all_signals ]
 
@@ -33,42 +35,49 @@ gtkwave::/Edit/Data_Format/Analog/Step
 gtkwave::/Edit/Data_Format/Signed_Decimal
 gtkwave::/Edit/Insert_Analog_Height_Extension
 
-gtkwave::highlightSignalsFromList "tb.i_converter.i_filtered\[15:0\]"
+gtkwave::highlightSignalsFromList "tb.i_converter.switch\[4:0\]"
+gtkwave::/Edit/Data_Format/Analog/Step
+gtkwave::/Edit/Data_Format/Decimal
+
+gtkwave::highlightSignalsFromList "tb.i_converter.i_filtered\[16:0\]"
 gtkwave::/Edit/Data_Format/Analog/Step
 gtkwave::/Edit/Data_Format/Signed_Decimal
 gtkwave::/Edit/Insert_Analog_Height_Extension
 
-gtkwave::highlightSignalsFromList "tb.i_converter.q_filtered\[15:0\]"
+gtkwave::highlightSignalsFromList "tb.i_converter.q_filtered\[16:0\]"
 gtkwave::/Edit/Data_Format/Analog/Step
 gtkwave::/Edit/Data_Format/Signed_Decimal
 gtkwave::/Edit/Insert_Analog_Height_Extension
 
-gtkwave::highlightSignalsFromList "tb.i_converter.abs_i\[15:0\]"
+gtkwave::highlightSignalsFromList "tb.i_converter.abs_i\[16:0\]"
 gtkwave::/Edit/Data_Format/Analog/Step
 gtkwave::/Edit/Data_Format/Decimal
 gtkwave::/Edit/Insert_Analog_Height_Extension
 
-gtkwave::highlightSignalsFromList "tb.i_converter.abs_q\[15:0\]"
+gtkwave::highlightSignalsFromList "tb.i_converter.abs_q\[16:0\]"
 gtkwave::/Edit/Data_Format/Analog/Step
 gtkwave::/Edit/Data_Format/Decimal
 gtkwave::/Edit/Insert_Analog_Height_Extension
 
 gtkwave::highlightSignalsFromList "tb.i_converter.sum_abs\[16:0\]"
 gtkwave::/Edit/Data_Format/Analog/Step
 gtkwave::/Edit/Data_Format/Decimal
-gtkwave::/Edit/Insert_Analog_Height_Extension
 
-gtkwave::highlightSignalsFromList "tb.i_converter.ema\[17:0\]"
+gtkwave::highlightSignalsFromList "tb.i_converter.ema\[16:0\]"
 gtkwave::/Edit/Data_Format/Analog/Step
 gtkwave::/Edit/Data_Format/Decimal
-gtkwave::/Edit/Insert_Analog_Height_Extension
 
 gtkwave::highlightSignalsFromList "tb.i_converter.rms_out\[10:0\]"
 gtkwave::/Edit/Data_Format/Analog/Step
 gtkwave::/Edit/Data_Format/Decimal
 gtkwave::/Edit/Insert_Analog_Height_Extension
 
-gtkwave::highlightSignalsFromList "tb.i_converter.switch\[4:0\]"
+gtkwave::highlightSignalsFromList "tb.i_convert.ina\[23:0\]"
+gtkwave::/Edit/Data_Format/Analog/Step
+gtkwave::/Edit/Data_Format/Signed_Decimal
+gtkwave::/Edit/Insert_Analog_Height_Extension
+
+gtkwave::highlightSignalsFromList "tb.i_convert.ing\[23:0\]"
 gtkwave::/Edit/Data_Format/Analog/Step
 gtkwave::/Edit/Data_Format/Decimal
 gtkwave::/Edit/Insert_Analog_Height_Extension

labs/3_music/3_10_spectrum_analyzer/lab_top.sv

@@ -72,12 +72,12 @@ module lab_top
             mic_11bit <= '0;
             led       <= '0;
         end
-        else if (|(mic [23:16] ^ {8 {mic [23]}})) begin // overflow prevention
-            mic_11bit <= {mic [23], {10 {~mic [23]}}};
-            led       <= '1;                            // overflow warning
+        else if (mic [17] != mic [18]) begin // overflow prevention
+            mic_11bit <= {mic [18], {10 {~mic [18]}}};
+            led       <= '1;                 // overflow warning
         end
         else begin
-            mic_11bit <= mic [16:6];
+            mic_11bit <= mic [17:7];
             led       <= '0;
         end
     end

labs/3_music/3_10_spectrum_analyzer/spectrum.sv

@@ -10,8 +10,8 @@ module spectrum
                w_y                 = $clog2 ( screen_height ),
 
     // Frequency bands of the spectrum analyzer
-        logic  [0:11] [13:0] freq  = '{132, 152, 174, 200, 230, 264,
-                                       303, 348, 400, 458, 525, 600}
+        logic  [0:11][13:0] freq  = '{132, 152, 174, 200, 230, 264,
+                                      303, 348, 400, 458, 525, 600}
 )
 (
     input                        clk,
@@ -30,16 +30,16 @@ module spectrum
 
     //------------------------------------------------------------------------
 
-    logic [11:0] [16:0] band_count;     // defines period converter.pulse_out
-    logic [11:0] [10:0] rms_out;        // result of spectrum analyzer band
-    logic               white;
-    logic [      w_y:0] h_scr;
-    logic signed [ 9:0] [10:0] in;
+    logic        [11:0][16:0] band_count; // defines period converter.pulse_out
+    logic        [11:0][10:0] rms_out;    // result of spectrum analyzer band
+    logic                     white;
+    logic        [     w_y:0] h_scr;
+    logic signed [ 9:0][10:0] in;
 
-    assign h_scr = screen_height;       // shifting minimum height of strip
-    assign red   = {w_red   {white}};   //
-    assign green = {w_green {white}};   // - color selection
-    assign blue  = {w_blue  {white}};   //
+    assign h_scr = screen_height;         // shifting minimum height of strip
+    assign red   = {w_red   {white}};     //
+    assign green = {w_green {white}};     // color selection
+    assign blue  = {w_blue  {white}};     //
 
     //------------------------------------------------------------------------
     //
@@ -48,7 +48,7 @@ module spectrum
     //------------------------------------------------------------------------
 
     // Calculation of control pulses from system clock and band
-    function automatic logic [16:0] b (input [13:0] f );
+    function automatic logic [16:0] b (input [13:0] f);
     b = (clk_mhz * 31250) / f;
     endfunction
 
@@ -62,7 +62,7 @@ module spectrum
 generate
 
     if (screen_width == 800) begin : screen_w_800
-    always_ff @ (posedge clk or posedge rst) begin
+    always_ff @(posedge clk or posedge rst) begin
         if (rst)
             white <= '0;
         else
@@ -85,7 +85,7 @@ generate
     end
 
     else if (screen_width == 640) begin : screen_w_640
-    always_ff @ (posedge clk or posedge rst) begin
+    always_ff @(posedge clk or posedge rst) begin
         if (rst)
             white <= '0;
         else
@@ -108,7 +108,7 @@ generate
     end
 
     else begin : screen_w_480
-    always_ff @ (posedge clk or posedge rst) begin
+    always_ff @(posedge clk or posedge rst) begin
         if (rst)
             white <= '0;
         else

labs/3_music/3_10_spectrum_analyzer/surfer.scr

@@ -9,6 +9,8 @@ variable_add tb.i_converter.sum_abs
 variable_add tb.i_converter.ema
 variable_add tb.i_converter.rms_out
 variable_add tb.i_converter.switch
+variable_add tb.i_convert.ina
+variable_add tb.i_convert.ing
 
 item_focus a
 item_set_format Signed
@@ -32,5 +34,9 @@ item_focus j
 item_set_format Unsigned
 item_focus k
 item_set_format Unsigned
+item_focus l
+item_set_format Signed
+item_focus m
+item_set_format Unsigned
 
 scope_select tb.i_converter