tst_delay.tb.v


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// try to figure out how iverilog samples edges
`timescale 1us/1us

module tst_delay_tb (
);

reg clk_i;
reg data_i;
wire data_o;

tst_delay uut(
  .clk_i(clk_i),
  .data_i(data_i),
  .data_o(data_o)
);

string filename;
initial begin
`ifdef DUMP_FILE_NAME
  filename=`DUMP_FILE_NAME;
`else
  filename="tst_delay.lxt2";
`endif
  $dumpfile(filename); $dumpvars();
  clk_i = 0;
  data_i = 0;
end

always #10 clk_i = ~clk_i;

initial begin
  #9
  data_i = 1;
  #2
  data_i = 0;
  // note the <= assignment
  #19
  data_i <= 1;
  #1
  data_i = 0;
  // note the = assignment
  #19
  data_i = 1;
  #1
  data_i = 0;
  #40
  $finish();
end

endmodule