iverilog/ivtest/fpga_tests/timer_tb.v

59 lines
1.5 KiB
Verilog

/*
* Copyright (c) 2003 Stephen Williams (steve@icarus.com)
*
* This source code is free software; you can redistribute it
* and/or modify it in source code form under the terms of the GNU
* General Public License as published by the Free Software
* Foundation; either version 2 of the License, or (at your option)
* any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
*
* $Id: timer_tb.v,v 1.1 2003/04/01 05:55:24 stevewilliams Exp $
*/
`timescale 1us / 1us
module main;
wire rdy;
reg reset, clk;
timer dut(.rdy(rdy), .clk(clk), .reset(reset));
always begin
#5 clk = 1;
#5 clk = 0;
end
initial begin
$dumpvars(0, main);
#7 reset = 1;
#1 if (rdy !== 0) begin
$display("FAILED: reset did not clear rdy. rdy=%b", rdy);
$finish;
end
#6 reset = 0;
end
always @(posedge clk)
if (rdy === 1) begin
$display("rdy=%b at time=%0d", rdy, $time);
if ($time != 175) begin
$display("FAILED: timer ran out incorrectly.");
$finish;
end
$display("PASSED");
$finish;
end
endmodule // main