led_toggle.tb.v


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`timescale 1us/1ns

module led_toggle_tb (
);

reg clk_i;
reg rst_i;
reg key_i;
wire [5:0] led;
integer i = 0;

led_toggle #(.STABLE_PERIOD(2)) uut(
  .rst_i(rst_i),
  .clk_i(clk_i),
  .key_i(key_i),
  .led(led)
);

string filename;
initial begin
`ifdef DUMP_FILE_NAME
  filename=`DUMP_FILE_NAME;
`else
  filename="led_toggle.lxt2";
`endif
  $dumpfile(filename); $dumpvars();
  clk_i <= 0;
  key_i <= 1'b1;
  #1
  rst_i <= 0;
  #1
  rst_i <= 1;
end

always #10 clk_i = ~clk_i;


initial begin
  // initial key press
  #25
  key_i <= ~key_i;
  #40
  key_i <= ~key_i;

  // try bouncing

  #50

  for (i=0; i < 19; i = i + 1) begin
    #20
    key_i <= ~key_i;
  end
  #200
  key_i <= ~key_i;

  #205
  $finish();
end

endmodule