`timescale 1 ns/1 ns // time-unit, precision

`default_nettype none

module Debouncer_tb();

parameter CLOCK_HZ = 10_000_000;

parameter HALF_PERIOD_NS = 1_000_000_000 / (2 * CLOCK_HZ);

// Clock generator

reg Clock = 1'b1;

always begin

#HALF_PERIOD_NS;

Clock = !Clock;

end

// Delay task

task Delay_us(input integer DelayTime_us);

repeat((CLOCK_HZ / 1_000_000) * DelayTime_us)

@(posedge Clock);

endtask

// Variable dump

initial begin

$dumpfile("debouncer.vcd");

$dumpvars(0, Debouncer_tb);

end

// Variables

reg Reset = 1'b0;

reg Button = 1'b0;

// Test sequence

integer i;

initial begin

$timeformat(-6, 3, "us", 10);

$display("===== START =====");

$display("CLOCK_HZ = %9d", DUT.CLOCK_HZ);

$display("PERIOD_US = %9d", DUT.PERIOD_US);

$display("DELAY = %9d", DUT.DELAY);

$display("WIDTH = %9d", DUT.WIDTH);

@(posedge Clock)

Reset = 1'b1;

// Toggle state of Button signal and wait longer tine in each loop

for(i=1; i<=20; i=i+1) begin

Delay_us(i);

Button <= ~Button;

end

@(posedge Clock)

$display("====== END ======");

$finish;

end

// Instantiate device under test

Debouncer #(

.CLOCK_HZ(CLOCK_HZ),

.PERIOD_US(10)

) DUT(

.Clock(Clock),

.Reset(Reset),

.NoisySignal_i(Button),

.FilteredSignal_o()

);

`default_nettype wire