Ich arbeite an einem Verilog-Programm, das eine Art Audio-Wellenform (von meinem Mikrofon aufgenommen) über einen VGA anzeigen soll. Ich verwende das folgende Modul, um neue Audio-Samples einzufügen, und tausche es mit dem Puffer aus, der zum Speichern der Werte für den aktuellen Frame verwendet wird, der vom VGA-Controller gerendert wird.
module audio_shift_buffer#
(parameter BUFFER_SIZE = 1280)
(
input vga_clk,
input smp_clk,
input [7:0] sample_in,
input sample_in_valid,
input [10:0] vga_read_index,
output reg [7:0] vga_read_out,
input vga_swap_buffers
);
reg [7:0] smp_buf[BUFFER_SIZE - 1:0];
reg [7:0] vga_buf[BUFFER_SIZE - 1:0];
integer i;
always @(posedge smp_clk)
if(sample_in_valid) begin
for(i = 0; i < BUFFER_SIZE - 1; i = i + 1)
smp_buf[i] <= smp_buf[i + 1];
smp_buf[BUFFER_SIZE - 1] <= sample_in;
end
integer j;
always @(posedge vga_clk) begin
if(vga_swap_buffers)
for(j = 0; j < BUFFER_SIZE; j = j + 1)
vga_buf[j] <= smp_buf[j];
vga_read_out <= vga_buf[vga_read_index];
end
endmodule
Dieses Modul wird zusammen mit dem vga_controller in meinem Top-Level-Audiovisualisierer erstellt.
module audio_visualizer
(
input clk,
input m_data,
output m_clk,
output reg m_lr = 1'b1,
output vga_hs, vga_vs,
output [3:0] vga_r, vga_g, vga_b,
input sw
);
wire vga_clk;
wire [10:0] sound_level_index;
clk_wiz_0 cwz(clk, vga_clk);
wire [7:0] vga_read;
wire swap;
audio_shift_buffer sb
(
.vga_clk(vga_clk),
.smp_clk(vga_clk),
.sample_in({8{sw}}),
.sample_in_valid(swap),
.vga_read_index(sound_level_index),
.vga_read_out(vga_read),
.vga_swap_buffers(swap)
);
vga_controller v
(
.vga_clk(vga_clk),
.hsync(vga_hs),
.vsync(vga_vs),
.r(vga_r),
.g(vga_g),
.b(vga_b),
.sound_level_index(sound_level_index),
.sound_level(vga_read),
.swap_buffers(swap)
);
endmodule
Endlich ist hier mein VGA-Controller.
module vga_controller#
(
parameter H_VISIBLE = 1280,
parameter H_FRONT_PORCH = 72,
parameter H_BACK_PORCH = 216,
parameter H_SYNC = 80,
parameter V_VISIBLE = 720,
parameter V_FRONT_PORCH = 3,
parameter V_BACK_PORCH = 22,
parameter V_SYNC = 5
)
(
input vga_clk,
output [3:0] r, g, b,
output reg hsync, vsync,
output [10:0] sound_level_index,
input [7:0] sound_level,
output reg swap_buffers
);
localparam H_RES = H_VISIBLE + H_FRONT_PORCH + H_BACK_PORCH + H_SYNC;
localparam V_RES = V_VISIBLE + V_FRONT_PORCH + V_BACK_PORCH + V_SYNC;
localparam H_IN_VIDEO = H_VISIBLE;
localparam H_IN_BP = H_IN_VIDEO + H_BACK_PORCH;
localparam H_IN_SYNC = H_IN_BP + H_SYNC;
localparam H_IN_FP = H_IN_SYNC + H_FRONT_PORCH;
localparam V_IN_VIDEO = V_VISIBLE;
localparam V_IN_BP = V_IN_VIDEO + V_BACK_PORCH;
localparam V_IN_SYNC = V_IN_BP + V_SYNC;
localparam V_IN_FP = V_IN_SYNC + V_FRONT_PORCH;
reg [10:0] x = 0, y = 0, next_x, next_y;
always @(posedge vga_clk) begin
x <= next_x;
y <= next_y;
end
always @* begin
next_y = y;
if(x == H_RES - 1) begin
next_x <= 0;
if(y == V_RES - 1)
next_y <= 0;
else
next_y <= y + 1;
end else
next_x <= x + 1;
end
always @(posedge vga_clk) begin
hsync <= ~(next_x >= H_IN_BP && next_x < H_IN_SYNC);
vsync <= ~(next_y >= V_IN_BP && next_y < V_IN_SYNC);
swap_buffers <= next_y == V_IN_VIDEO && next_x == 0;
end
reg vout_enable;
always @(posedge vga_clk) begin
vout_enable <= next_x < H_IN_VIDEO && next_y < V_IN_VIDEO;
end
wire [10:0] request_x = next_x + 1;
assign sound_level_index = request_x < H_IN_VIDEO ? request_x : 0;
wire [10:0] ubound = 11'd360 + sound_level;
wire [10:0] lbound = 11'd360 - sound_level;
reg color;
always @(posedge vga_clk) begin
color <= next_y <= ubound && next_y >= lbound;
end
assign r = {4{color & vout_enable}};
assign g = {4{color & vout_enable}};
assign b = {4{color & vout_enable}};
endmodule
Im Moment habe ich es nur an einen Schalter auf meinem Board angeschlossen. Es fügt nach jedem Frame ein "Muster" des Schalters hinzu. Als ich es getestet habe, scheint alles perfekt zu funktionieren. Weiße Balken laufen über den Bildschirm, wenn der Schalter eingeschaltet ist, andernfalls schwarz. Ich erhalte jedoch die folgenden Synthesewarnungen, die für mich keinen Sinn ergeben. Die Elemente, die es auflistet, werden eindeutig verwendet. Wenn sie es nicht wären, bezweifle ich, dass das Programm funktionieren würde. Es listet sogar vga_read_out als unbenutzt auf, was nicht wahr sein kann, da der Controller nur so Daten abrufen und das richtige Ergebnis anzeigen kann. Was geht hier vor sich?
[Synth 8-3332] Sequential element (\smp_buf_reg[1279][5] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1279][4] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1279][3] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1279][2] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1279][1] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1279][0] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[0][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[0][5] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[0][4] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[0][3] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[0][2] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[0][1] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[0][0] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_read_out_reg[7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_read_out_reg[5] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_read_out_reg[4] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_read_out_reg[3] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_read_out_reg[2] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_read_out_reg[1] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_read_out_reg[0] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1279][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1278][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1278][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1277][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1277][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1276][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1276][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1275][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1275][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1274][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1274][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1273][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1273][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1272][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1272][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1271][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1271][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1270][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1270][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1269][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1269][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1268][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1268][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1267][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1267][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1266][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1266][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1265][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1265][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1264][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1264][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1263][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1263][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1262][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1262][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1261][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1261][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1260][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1260][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1259][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1259][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1258][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1258][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1257][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1257][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1256][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1256][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1255][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1255][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1254][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1254][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1253][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1253][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1252][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1252][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1251][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1251][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1250][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1250][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1249][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1249][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1248][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1248][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1247][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1247][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1246][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1246][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1245][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1245][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1244][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1244][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1243][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1243][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1242][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1242][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1241][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1241][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\smp_buf_reg[1240][7] ) is unused and will be removed from module audio_shift_buffer.
[Synth 8-3332] Sequential element (\vga_buf_reg[1240][7] ) is unused and will be removed from module audio_shift_buffer.
Wenn es sie entfernt, sind sie tatsächlich unbenutzt, aber es ist nicht immer offensichtlich, warum.
Ich denke, in Ihrem Fall ist der Grund:
.sample_in({8{sw}}),
Der Synthesizer ist schlau genug, um zu erkennen, dass die Bits in jedem Wort Ihrer Erinnerungen ( smp_bufund vga_buf) identisch sind. Infolgedessen entscheidet es, dass es keinen Sinn macht, die Hardware zu duplizieren, es könnte genauso gut nur eine 1-Bit breite Version haben.
Wo immer das 8-Bit breite Wort verwendet wurde, füllt es einfach alle 8 Bits mit dem Wert aus dem neuen 1-Bit breiten Wort. Dies führt zum gleichen Verhalten, jedoch mit weniger Logik.