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forked from tanchou/Verilog

Init et début de réflexion sur le projet

This commit is contained in:
Gamenight77
2025-04-22 09:56:06 +02:00
parent 39acfbe25b
commit 3bb56e2f57
48 changed files with 21 additions and 0 deletions

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`timescale 1ns/1ps
module tb_ultrasonic_fpga;
reg clk = 0;
reg rst = 1;
reg start = 0;
reg echo = 0;
wire trig_out;
wire [8:0] distance;
time t_start, t_end;
// Clock 27MHz => periode = 37ns
always #18 clk = ~clk;
ultrasonic_fpga uut (
.clk(clk),
.rst(rst),
.start(start),
.echo(echo),
.trig_out(trig_out),
.distance(distance)
);
initial begin
$dumpfile("ultrasonic.vcd");
$dumpvars(0, tb_ultrasonic_fpga);
// Reset
#100;
rst = 0;
// Start
#100;
start = 1;
#40;
start = 0;
wait (trig_out == 1);
t_start = $time;
// Attendre qu'il redescende
wait (trig_out == 0);
t_end = $time;
$display("Trig HIGH duration: %0dns", t_end - t_start);
if ((t_end - t_start) >= 9500 && (t_end - t_start) <= 10500) begin
$display("Trigger signal is high for 10us.");
#10;
echo = 1;
#5800;// Echo dure 5800ns ( 100 cycles @ 27MHz => 100 cm aller-retour)
echo = 0;
end else begin
$display("Trigger signal is NOT high for 10us.");
end
#500;
// Affiche la distance
if (distance > 0) begin
$display("Distance measured: %d cm", distance);
end else begin
$display("No distance measured.");
end
$finish;
end
endmodule

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module ultrasonic_fpga #(
parameter integer CLK_FREQ = 27_000_000 // Fréquence d'horloge en Hz
)(
input wire clk,
input wire start,
inout wire sig, // Broche bidirectionnelle vers le capteur
output reg [15:0] distance, // Distance mesurée en cm
output reg [2:0] state = IDLE
);
reg [15:0] trig_counter;
reg [31:0] echo_counter;
reg sig_out;
reg sig_dir; // 1: output, 0: input
assign sig = sig_dir ? sig_out : 1'bz;
wire sig_in = sig;
localparam IDLE = 3'd0,
TRIG_HIGH = 3'd1,
TRIG_LOW = 3'd2,
WAIT_ECHO = 3'd3,
MEASURE_ECHO = 3'd4,
DONE = 3'd5,
WAIT_NEXT = 3'd6;
localparam integer TRIG_PULSE_CYCLES = CLK_FREQ / 100_000; // 10us pulse
localparam integer DIST_DIVISOR = (58 * CLK_FREQ) / 1_000_000; // pour conversion us -> cm
localparam integer MAX_CM = 350;
localparam integer TIMEOUT_CYCLES = (MAX_CM * 58 * CLK_FREQ) / 1_000_000;
localparam WAIT_NEXT_CYCLES = (CLK_FREQ / 1000) * 100; // 60 ms
reg [31:0] wait_counter;
always @(posedge clk) begin
case (state)
IDLE: begin
sig_out <= 0;
sig_dir <= 1;
distance <= 0;
if (start) begin
state <= TRIG_HIGH;
trig_counter <= 0;
end
end
TRIG_HIGH: begin
sig_out <= 1;
sig_dir <= 1;
if (trig_counter < TRIG_PULSE_CYCLES) begin
trig_counter <= trig_counter + 1;
end else begin
trig_counter <= 0;
state <= TRIG_LOW;
end
end
TRIG_LOW: begin
sig_out <= 0;
sig_dir <= 0; // Mettre en entrée
state <= WAIT_ECHO;
end
WAIT_ECHO: begin
if (sig_in) begin
echo_counter <= 0;
state <= MEASURE_ECHO;
end else if (echo_counter >= TIMEOUT_CYCLES) begin
distance <= 0;
state <= DONE;
end else begin
echo_counter <= echo_counter + 1;
end
end
MEASURE_ECHO: begin
if (sig_in) begin
if (echo_counter < TIMEOUT_CYCLES) begin
echo_counter <= echo_counter + 1;
end else begin
distance <= 0;
state <= DONE;
end
end else begin
distance <= (echo_counter * 1000) / DIST_DIVISOR;
state <= DONE;
end
end
DONE: begin
if (start) begin
wait_counter <= 0;
state <= WAIT_NEXT;
end else begin
state <= IDLE;
end
end
WAIT_NEXT: begin
wait_counter <= wait_counter + 1;
if (wait_counter >= WAIT_NEXT_CYCLES) begin
state <= TRIG_HIGH;
end
end
endcase
end
endmodule